Cutaway electric motor models Tom Chipley shows parts will help follow authors text heart system Electrics CAN SET SCREW ADAP FRONT BEARING about FIELD MAGNETS END BELLREAR BRUSHESBEARING 3 N\~ COMMUTATOR_ ARMATURE_CAPACITOR V. POLARIZED CONNECTOR w w w heart electric-powered airplane motor chapter describes whats motor provides some tips successful operation long useful life dont have know about elec tric motors enjoy flying Electrics youll ahead crowd Part 2 U Bob Kopski LAST MONTH highlighted features characteristics electric power noting advantages disadvantages showing varity electric-powered models broad range applicability con venience fun aspects relatively new form model power emphasized So much convincing Now does modeler average skill make hap pen Lets start getting know about electric motors sense knowledge about conventional gas power reciprocating enginesoften comes naturally feel comfortable familiar family car lawnmower engines Carburetor word unheard dinner table commutator thats bit unfamiliar unknown can bit scary purpose installment help feel comfortable electric motors describing some basics Ill get detail can use confidence Well cover some things should some things shouldnt may few things didnt know should Some things may seem necessary get started will surely help keep going Ill try make simple easy follow minimum heavy tech nical good dose plus plenty tidbits collected other single publication know Ill try arrange convenient sections can skip around interest need dictates easy future reference 1 Whats motor sections can skip over still start fly model other hand little bit information may help feel lot confident about subject because youll familiar what makes em hummmmmmm small direct current DC electric motors permanent magnet type used example batteryoperated toys applicances some auto accessories electric-powered air planes motors usually have two pieces strong magnetic material 40 Model Aviation motors typical readily available US modelers upper Astro 10 lower Leisure LT-50 Both have connecting wires convenient plugs well brush capacitors visible Leisure However have different kind prop adaptor i SQ Left Two kinds rear-end bells brushes connector cord has non-replaceable brushes well worn arms spring material Look closely may notice has no bearingthe result hard landing other rear-end assembly has replaceable brushes ball bearings armature shaft Coil springs provide bruah pressure left rear-end bell early Leisure motor other current Leisure LT-50 Center Two motor housings magnets intact left low-cost motor having front-end bell part drawn motor can Visible bearing two boles mounting screws two vent holes other housing has removable bells both ends Right Two typical armatures windings stripped oft clearly shows three poles poles made stacked thin iron laminations Drill marks top-most pole balancing final armature assembly Windings commutator visible left armature Left Hatch flipped back its tape hinge reveals rear cobalt 05 motor connector charging jack Look carefully might see brush dust inside fuselage hatch Note smooth nose block Persuader Acrobatic model Right Props 6 9-in diameter various prop adaptors held armature shafts setscrews pressed-on adaptors dont easily come off arent used much anymore Props may have drilled fit adaptors After boring balance achieve peak smoothness fixed opposite other inside round iron can housing field poles form strong magnetic field inside can armature assembly rotate within ends housing capped end bells ai least can usually removed Sometimes end simply part formed motor can end bells have centered bearings either bushing type ball type support armature shaft armature shaft holds stack thin iron laminations shaped form poles always odd number poles usually three seven Most small motors have three unmagnetized armature poles wound insulated copper wire. windings connected another part armature shaft called commutator commutator round insulator metal segments outer surface number segments equals number armature poles really rotary switch sequentially connects power source armature windings done through two spring-loaded sliding con tacts brushes ride ihe commutator segments armature assembly rotates two brushes normally mounted rear-end bell insulated other motor housing commutator segments bi-ushes carefully positioned relative armature poles housing field magnets respectively voltage applied external brush connections some ar mature polcs become electromagnetized just right place pushed others pulled field magnets forces cause armature begin rotating As commutator rotates new position power directed switched next winding set new poles will now pushed pulled stationary magnetic field timing characteristic similar auto engine sures proper sequential firing cylin ders As action continues motor armature spins seemingly smooth con tinuous rotationeven though electrical current being switched winding set next rapidly creating instant elec tromagnets out otherwise plain iron armature poles Start-up current can very heavy surge Once spinning however unloaded motor normally draws relatively little cur rent because sniall amounts electri cal power required overcome bear ing brush friction some other small power losses mechanical load applied motor shaft like propeller motor has work consequently electrical input power must increase Putting another way cant get something nothing Some examples illustrate will given later tn application motor acts convert extra electrical power input propeller thrust 2 Motors model use make motor suited model use some fea tures added basic machinery de scribed above Lets look impor tant ones some detail touch several others Prop adaptor fitting armature shaft extflding front motor either press-fitted held io shaft setscrew prefer shafts small flat setscrew get good bite onto prop adaptor may have threaded extension oh Which prop placed held washer nutvery similar gas engines prop adaptor may have inside thread prop held screw washer similar some small glow engines latter case multiple washers may supplied allow prop screw accept range prop hub thicknesses change screw length Its probably October 1983 41 5-40 thread almost impossible find anywhere B Motor mount Some method niounting motor needed Most motors have two four threaded holes frontend bell can used partially se cure motor Some motors have metal mounting clamps slip around housing form two beams similar glow engine Others have matching plastic mounts ease task installation personal preference structural motor mount 1 use part fuselage struc ture support motor often con junction aforementioned front-bell screw holes reducer mounting holes dont care slip motor tight tube type friction motor-holder popular early days Electrics Motor mounting sometimes stumbling block first-time Electric flier some proven methods will covered detail future meantime look accompanying photos get general idea C Venting thing am very big adequate venting motor During flight motor can develop significant internal heat fact properly used motor can get hot enough melt solder connections rapidly wear brushes As far Im concerned theres no such thing too much venting motor Most motors have openings front-end bell well rear vicinity brushes Vents must kept clear mounting motor provision must made motor air exit model struc ture Well see some ways future installment Ive learned hard way avoid motors no venting D Brushes etc very nice feature some motors replaceable brushes gen erally found costly and/or larger motors Brushes wear away fine dark colored brush dust exits hotor vents deposited some extent fuselage Dont worry powder harmful structure like oil Brush wear related hard work motor and/or effective venting Also brushes made differ ent materials affects wear rate lower-cost motors brush re placement possible brush wear may determining factor long motor lasts especially motor worked hard other hand once sold plane over 400 flights logged low-cost motor half original brush material remained time motor tached Continued page 132 42 Model Aviation four pictures show inside out kind structural motor mount motor mounted center pictures Astro 10 Dan Gravers sport flier named Friendly Two formers I/ Lite Ply provide support fore aft Cutout rear clearly offset right thrust obvious offset Dan has downthrust Nylon landing gear straps hold motor front former 6-32 screws front-end bell No 2 sheet-metal screws former Make cutouts round snug fit motor wrap plastic tape fixes minor misfits Two fuselage fronts having same kind structural motor mount motor slides rear through top hatch up against nylon right-angle brackets latter CyA glued 1/6. ply tube epoxied inside bored balsa block block turn glued fuselage sides carved smooth shape right fuselage has bottom skids prop-stop tubing 2 oclock spot variety motor mounts shown left plastic beam mount slips over motor housing setscrew holds tight Next structural motor mount natural part fuselage assembly third Mabuchi motor metal U-shaped clamps meet form mounting beams clamps also serve flux rings note air vents arent covered right another plastic mount radial type also held setscrew attaches cutout firewall four screws Thrust adlustments direction easy radial mount Phase Art Best Custom Screen Sportswear \~kl 4893SNu Piper Cub NATS Shirts Still Available See Bealeton VASept 17 8 18 Greenville SCSept 23 Stratford CTOct 1 FAI Championships Pensacola FLOct 10-14 Designs just come aviation designs available top quality line sportswear designs direct printno heat transfer Three color B-25. Piper Cub. Bee. P40 Warha wks kker D VII. P-3. AT-6. Christen Eagle. Pitts Special. Citabria. P47 Thunderbolt earman Curtis enny. Corsair. coaches shirtS1295TShirt$695 LadiCs TopSSSOLong Sleeve T$795 Shorts$5SSBesebell$S95 Lined JacketS2195Football$S95 Tote Bag$9SSweetshirt$950 Tire coverS1495Hooded Sweot$1495 HatS595 Wide choice colors aizesi Send $100 new illustrated Brochure Refundable First Order Name Address cityStateZip DesignSize Color now accept MasterCard & Visa TO ORDER Send check money order Shipping $1-is add 5150 Over $15 add 10% Maryland residents add 5% taxI Phase Art 17102 Earlham Ct Upper Marlboro MD 20772 1301 8433050 wings find have root rib WI little crooked have tapered fairing blocks properly now good timc fit wid root fuselage hLindy sanding block Covering may use whatever covering material desirc though highly recom mend MonoKote combination like cover bottom surfaces dark easy-to-see color cover top lighter brighter color pleases eSe Radio installation fuselage little smallonly wide servo area room two medium-size servos like Kraft KPS-14 though like small Futaba S-2t mounting two S-20s forward possible leaves little access space allows mounting switch Bulkhead F2 Snap-Lip pushrods install receiver bet dre install switch switch button sticking ward through F can lift canopy easily operate use larger servos will have mount switch dit receiver between Bulkheads F3 F4 battery compartment will take Kraft KB-4M 450 Futaba NR-4G 225 pack Flying Scooter very stable glides fairly fgst turns tightly minimum loss altitude stalling angle-of-attack fairly high Best unlike flying-stab planes easy ginner tly recommend balance point CG placed right niiddle main spar also place tow hook right CG After try way can move CG and/or tow hook wherever yov can fly best good way -Add weight nose block balkust sheet lead can buy local plumbing shop cut shape tin snips used Ii-in wing wire primarily cause /4-in brass tubing required wAs same width spars easy align together desire can shim down wing wire size %s inserting A2-in GD /6-in ID tubing inside /4-in GD /32-in ID brass tubing will provide wing little give under sharp loads Sailplane design has its advantages disadvantageshigh lift high drag low drag low lift etc No design really perfect however feel Scooter good compromise Good lift Radio Technique/Myers Continued page 39 problems thanks Al Watson Gary Wild reports kind help makes job easier really enjoy hearing fr6m folks go out get valid test data selves instead wasting time listening Know-It-AIls havent actually done anything What else caii tell potential various kinds interference still present should monitor band order know what avoid its still good idea check DFC planning contest encounter problems new RC channels re port DFC Beyond can fly new RC channels con fidence Have acquired new hobby Im slow answering letters apologize know excuses Recently bought Kaypro II Word Processor attempt catch up letters pile Frequency Committee mail among other things Up till now Ive using WW II surplus Royal KMM typewriter needs new rubber nobody stocks parts Dick Jannson says should ashamed admit three kids college time what else would expect Anyhow see Bob Aberle spending 40 hours week Frequency Committee businessnow Im trying find way get job done smaller investment time Kayproll seems help picked Kaypro LI because meets needs complete cheapest complete package local support As Ive said before about hobby items believe important have local dealer support its possible save little money going through mail Youll have make up own mind about Im knocking mailorder houses Im dogmatic about either want something isnt carried locally like Circus Radios Kalt Helicopters dont have other choice except So call somebody toll-free line want parts just really didnt buy thing start other hobby seems have effect So readers have bright ideas about get best out tool about letting know about Kaypro II runs CP/M Version 22 Kaypro II trademark Kaypro Corp 533 Stevens Ave Solana Beach CA 92075 George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 Electrics/Kopski Continued page 42 same new As brushes wear frequently wear unevenly brush will wear much rapidly other ddnt know happens bUt does alwys put two new ones As new motor always break-in new brushes allowing motor run no prop very small prop cooling about 24 hours about halfthe normal voltage Instructions some elec tric motor systems discuss some come factory break-in break-in allows new brushes wear shape commutator seat better good 132 Model Aviation WAYNE ULERYS 1/3 SCALE LASER 200 THE PLANE THAT WON THE WEST span 9825 Wing area 1615 sq 18 lbs Eight LASERS flown 1982 T0C placed top twelve. Unique easy wing construction Foam cutting equipment required Special instructions pictures wing assembly Fiberglass cowl wheel pants plastic canopy 6061 T-6 aluminum wing spar 2024 T-4 landing gear available Information parts plans order SASE $2000 per set rolled plans Postage paid t5e Continental LISA Wayne Ulery 2564 Fox Hollow Rd Springfield Ohio 45502 both mechanical electrical reasons Commutators much harder mate rial brushes nomally wear away However brushes al lowed wear down completely metal brush arm brush springs begin ride commutator will wear tt will probably become scored motor performance will decline electrical noise due ex cessive sparking likely commutator could permanently ruined avoid problem best look brushes occasionally especially re placeable Some visible through bent holes disassembly necessary inspection Others easily removed exter nally brush holders unscrewing caps Handle brushes carefully cleanly replace same way came out Ive seen other problems brushcommutator area Some motors may begin display noticeable performance drop erratic running no apparent reason often associated excessive brush sparking possibly radio glitches may due inadequate brush pressure though brushes show little wear brush arms spring material lower-cost motors become overheated due motor being overworked some other reson may lose some tension Another effect high heat can com mutator distortion commutator gets out round brush bounce occurs case brushes excellent condition cant job fact Ive seen happen motors no way overworked commutator defective start can seen during break-in unloaded unpropped motor runs erratically can actually feel rotational irregulatiry hand commutator out round lay running motor table can watch twitch Use warranty card should motor defective received Both conditions inadequate brush pressure out-of-round com mutator can appreciated better apply ing some light pressure either brush through vent hole toothpick motor speed picks up smooths out no ticeably chances prob lems exists have relatively new cobalt motor has treated considerable care two occasions far performance suddenly dropped off Aerobatics model just wouldnt its usual tricks Close inspection revealed nothing unusual brushes commutator looked good battery pack etc normal brushes cobalt motor ride square brush guide tubes have coil springs brush pressure Upon re assembling brushes same brush same holder same orientation motor its old self again same thing happened visitor last years Electric Fly guess brushes become little snug guides pressure effectively reduced Perhaps some brush dust clogs guide bit Anyway removing brushes wiping tissue cleaning guide tube dry pipe cleaner does trick sure handle brushes carefully keep fingers off avoid possible con tamination Sometimes above conditions apply symptoms similar motor has run hard resulting high brush heat some brush material may smeared heavily commutator sur face prevent good electrical contact Try cure Take prop off run motor normal battery pack two three minutes Replace prop tached rpm before after may see noticeable improvement possible recommend making note motor/battery performance new after break-in generally note rpm particular prop size make battery voltage time Later theres question about performance data can compared unlike rangechecking radio rechecking under same conditions later date crash hard bump prop prop adaptor can easily bend armature shaft resulting obvious wobble vi bration Sometimes shaft can straight ened prop will run true armature may still wobble due shaft bend behind front bearing also causes brush bounce erratic running Like brushes some higher-quality motors have armature replacements can bought cases such above recourse unless youre ma chine work Sometimes impact can severe enough rear-end bell and/or bearing break get pushed out rearward-driven armature assembly Ive seen few crankshafts glow engines come through backplate too careful use flexible nylon prop and/or prop stop stop prop horizontal position minimize such problems E Bearings Electric motors models have either sleeve bearings ball bearings Usually sleeve bearings selflubricating self-centering motor 400 hts type new owner flew past 500 flights Finally bearing wear caused much noise embarrassed replaced motor about 12 dollars Thats about cost gallon you-know-what Ball bearings found larger and/or costly motors What kind un pleasant contradiction costly motor ball bearings non-replaceable brushes little like car nonreplaceable tires Given choice Im content sleeve bearings small motors Im convinced balls worth added cost kind flying may afford com petitive edge series flying addressed fun sport flying Whatever bearing type never add lu Con tinued page 136 THIS FUEL FEATURES RUST PREVENTION AGENTS ODETERGENTS OLUBRICATION WITH HIGH FLASH POINTS WETHNG AGENTS FOR MORE EFFICIENT AND DEPENDABLE FUEL FLOW OANTI-FOAMING AGENTS TO PREVENT LEAN RUNS KEEPS YOUR ENGINE RUNNING COOL OAN ODORLESS HIGHLY REFINED FUEL CHILDPROOF LIDS Available FAI 5 10 15 25 & 40% Nitro-Methane Contents Formulated synthetic lubricants Also available castor DEALERS WANTED DOMESTIC & OVERSEAS WE EXPORT competition tuel fast becoming THE CHOICE top protesonals ot tirst ro cash product Contact us price structures ordering information Manufacturers Major Brand Distilbutors Model Engines Kits Radios Accessones SUPER K Fuels brand KINGS RADIO CONTROL HOBBIES INTERNATIONAL 3960 West 16 Ave Hlaleah Florida 33012 305 557-2024 October 1983 133 1r specially formulated chemically balanced fuel top petformance minimum engine wear weather condition Electrics/Kopski Continued page 133 brication drop oil might find its way onto commutator surface brush material Thats end Im told F Other motor features Some other things make motor better use model aircraft often include wire set suitable polarized connector terminals easy connections Usually ca pacitors wired brush terminals help suppress electrical noise may otherwise interfere RC operation High-temperature insulation epoxy coat ing windings lacing wires commutator connections keep everything place good features too motors have finely finished bal anced armatures assure smooth vibrationfree operation Motors may have neutral tim ing turn equally well either direction others may have offset timing maximize performance normal di rection propeller use Some motors pack higher power han dling capability small case through use costly very high strength field mag nets such samarium cobalt material feature adds big bucks motor price armature shafts bend just easily sure pay particular attention land ing German Keller motor available flux rings metal bands slip over outside motor can make metal thicker Without case rela tively thin motor works best small props high revs case heavied-up rings motor develps higher torque turn larger props efficiently lower rpm Its like having variety motors 3 Motor size often subject much confusion beginners Its presently cause much ado modeling indus try Opinions vary to specify size classes Eventually some standards will emerge AMA SEAM Society Electric Aircraft Modelers other interested parties sort out best options necessarily simple task Un like gas engine typically char acterized its displacement cubic inches several candidate ways characterize classify electric motors way would measure physical size such armature perhaps overall motor weight Another way de scribe battery instead motor size class determined number and/or kind cells motor battery method used Europe FAt events will interesting see settled Eventually will important have some size designations allow orderly inevitable evolution competitive Elec tric events folks arent quite ready competition yet just trying get started series intended help As youll see some standards would very big help too First lets look what motor size has historically meant largest variety motors country have descriptions sound like gas engine sizes ex ample popular motor size 05 has come mean motor would swing same size prop about same rpm typical glow counterpart Thus 05 example would probably use 6-in diameter 4-in pitch prop would turn prop about same speed glow 049s Similarly electric IS might swine 8-4 prop sounds simple enough isnt Things changing Electric evolving some associated growing pains joys cobalt 05 example can easily out-power 049 glow engineand swing much heftier prop too Its really good ol 05 Other changes occurring too all-time favorites so-called 075 its old self anymore Despite same nomenclature catalog number windings now different long-developed familiarity goes out window least deserves new part number above given purpose confusing Rather illustrates creasine need size class standards reminds us present dynamics Builders Get f Better Start Season Using KIN-CRAFT Quality Line Polyester Resins Micro-Balloon Air-O-Fill Gloves Protective Fiberglass Cloth & Tapes 6 oz Cloth 1 4 & 6 Tapes Custom Cut Cloth Any Length Sandable Primers Thinner Accessories also Dust Masks Gator Grip Contact Cement Applicator Kits Engine Cleaner Oil Kits 2u Ii tj Ilobby Prod U IS Send self-addressed stamped envelope free catalogue discounts Dealer Distributor Inquiries Invited Kin-Craft Mig Ri 2 Box 481E Ashland KY 41101 606 928-4763 136 Model Aviation SUPERwings DIVISION oF HI JOHNSON MODEL PRODUCTS 11015 GLENOAKS BLVD PACOIMA CA 91331 SAILPLANE COMPONENTS CREATE YOUR OWN SUPER GLIDER WING FOAM CORES Floater Thermal & Slope FUSELAGES LUSTROLEEN 2 Meter Standard Open & Scale STAB FOAM CORES Rudder & Fin Cores COVERING MATERIALS White skin & Lustroleen WING RODS Wing Tongue Kits FOR HI JOHNSONS PORTFOLIO PRICE SHEET & ORDER FORM about sailplane construction & design using foam & plastic SEND $250 CHECK OR MO CA RES ADD SALES TAX AMA Clubs Giant Scalers Save 30%Order Direct Buckeye Balsa supplies AAA quality balsa certified aircraft plywood fine kits Aero Composites Double C Mfg Fliteglas Models Fourmost Products Kitty Hawk Models Dave Platt Precision Built Models R/C Kits Mfg VK ModIs Bob Dively Model Aircraft hobby shops Send $1 catalog Price applied first order Minimum Net Order $50 No sh pprng COD charges 216 533 3607 P0 Box 174 Canfield OH 44406 ALL SKEET ONE PIECE AAA GRADE KILN DRIED SANDED TO CLOSE TOLERANCES PED 100% Balsa Sheets36Light 46lb361/8 x 3453/16 sq 173/8 x 11/246 1/16 x 2331/16 x 3491/16 x 4481/4 sq 261/2 x 270 3/32 x 2403/32 x 3563/32x4561/4x3/8 30 1/8 x 2431/8 x 3671/8 x 4663/8 sq 37BalsaTriangles 3/16 x 2493/16 x 376 Sticks 6 1/4 x 2561/4 x 385 ched 40%1/4 x 1/425 3/8 x 3115 ets 423/8 x 3/830 1/16x3371/2 x 31393/32 x 4100 W1/2x1/235 3/32 x 3441/8 x 4108Basswood h Pine3/4x3/445 1/8 x 354BalsaSheets483/16x4120 cks For1 xl55 3/16 x 3621/16 x 3491/4 x 4131 Scale 1/4 x 3733/32 x 358Balsa Sticks36Lite Ply48 5/16x3851/8x3 711/8 x 6150 3/8 x 3883/16 x 3 821/16 x 1/409 1/2 x 31101/4x 33/32 x 1/410Birch Dowels 361/8 x 12300 3/4x31653/8x31241/Bsq.081/8 09 1/8x1/411 3/16113Ply Birch48 1/4141/64x12525 1 x3200 1/2x3155 1/8x1/2181/32x12425 1/16 X 4581/16 x 4763/16 sq.11Sendaddressed1/16 x 12435 3/32 x 4703/32 x 41/4 sq.16 1/8ic4801/8x41/4x1/221stanipedenvelope1/8x12450 3/16 x 4933/16 x 43/8sq.27 logue 1/4x4110 1/4x4134 318x1/232listingall sizesSPlyBirch48 3/32 x 12570 3/8x41653/8x4225 1/2sq.361/8x12585 1/2 x 4225Pine Sticks36 Trailing Edge 3/16 x 12585 NEWBalsa Sheets 30 1/8 sq.13361/4 x 12600 Quarter1/16 x 331 1/8 x 1/416 1/4*132 ScaleSizes3/32x337 1/8x3/820 5/16x11/439 accept Visa Master Card personal checks COD jiandling Charge $3 pay UPS Add $2 COD $3 extra PP SPO FPO 5% tax Texas US currency relatively new area model aviation So advised dont discouraged Some day future will good ol days' Electric new Standards lacking notwithstanding series will help get flying un derstand hows whys meantime consider lonely world df few US suppliers products electric-powered flight Im sure its long lean decade dedication per severance belief future thank stalwai-ts Im convinced major chunk modeldoms future de servedly Without wouldnt reading 4 When get good stuff nearing end Part Two series know readers may getting quite anxious get building flying something Thats quite under standable lets pause put whole Electric thing perspective Its rela tively new unfamiliar mLdelers including some very astute skilled Based inquiries receive subject continues bring far questions readily available answers Now consider popular continuing columns some modeling magazines devoted conventional engines Surely things have use bug enough everyone knows about right Nope Now consider basic arti cles have seen devoted electric motors electric flight batteries electric anything elseall unanswered questions right Look another way know someone flying group whos got together Hes guy experience engines always run just right maintains equipment specialist Helicopter Scale Rubber Com bat whatever guy knows awful lot about modeling general too knows what hes doing has good un derstanding basics uses full advantage series will have plenty to' examples go along its parallel goal convey basic understanding fundamental aspects electric-powered flight time-honored method teachingbasics plus examples Some text some lab work sorta under hat youll soon easily answering understanding such questions what motor needed fly what plane what should weigh assure much flight time Soon Electric products today will become dated will specific examples based dont want series become dated want continue basic value understanding utilization whatever new better prod ucts come along have reasod able acquaintance Elec tric works will have no trouble obtaining first-time continuing success Stay us youll person has together' Electric very anxious let suggest youre following series also keep eye contemporary magazines good source suitable Electric designs have already published MA alone has three four last year articles typically include electric system information design Later series will suggest guidelines motor plane combinations will assure success Also intallation coming As mentioned Part very versatile RC design Spectra can accommo Con tinued page 140 ATTENTION ERS October 1983 137 EPOXY GLASS COWLS FOR NOSEN PICA SIO MORGAN BALSA USA PLA TT CONCEPT FLEET HOSTETLER RCM T-CRAFT SHEBER P177S & SCALE SUPER CUB POKEER O7 BOEING P72 P26 F4B2 P464 SPARROW HA WE GEE BEE MOO r MACBRIEfSS TURBULEAIT CHRISTEN EAGLE BRISIGHELLAS STAROUSTEFf II A SCALE 1381 BABY FLYBABY AIRCAMPER PILOT JUNGMANN 735 SCALE 7/4 SCALE DECATIIALON PIPER PA- TB ft OThERS WHEEL PANTS FOR CITABRIA SrAROUS TER II PIUS SKYBOLT LIBERIYSPORT CHRISTEN EAGLE PBE HAWK STEARMAN STINSON SRB MULLIGAN & OTHERS BRAZED& HEAT-TREATED WIRE GEARS&CABANES LARGE SCALE PLANS AVAILABLE Send $100 latest list supply Modelers fiberglass parts plansWrite call us T & D FIBERGLASS SPECIALTIES 30925 eLOcK GARDEN CITY Mi 48135 PHONE 313 421-6358 r Finally.. 1/3 Scale Realism lightweight highly detailed realistic pilot figure scale R/C model aircraft figure Shown 1/3 scale civilian Seated approximately 125 tall 310 mm weighs 15 ounces comes complete including instructions painting fits 1/3 scale planes including Pitts Eagle Homebuilts ORDER YOURS TODAY Produced byPrice $1995 William M Hawke$200 shipping 7148 Lasting Light Way Columbia MD 21045 Ask dealer order diredt 1/4 scale coming soon L Electrics/Kopski Continued paqe 137 date variety electric power systems planned construction article Next up Part Three will discuss pro pellers electric power motors sole function convert energy stored battery propeller thrust Im sure will amazed just what takes turn prop various props com pare prop change affects flight performance think youll find Part Three enlightening though still fundamental also graphic unique dont think thing like has published before Part Four will devoted bat teries about batteries Installations planes follow Now answer title question good stuff will continue will eventually come together promise As continue challenge series Ive come appreciate its sizeable scope very difficult write compact complete simple Introduction Elec trics regard want thank wife Wilma MA Editor Carl Wheeley Columnist Bill Winter Electric flying friends KRCHerb Dirks John Hickey Heinz Koerner Don LeGower Dan Mittenfor critiquing drafts artworks helpful sugges tions Any questions related part earlier parts series may directed SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 RC Soaring/Pruss Continued page 45 helpful may have noticed skipped Fri days activity did because thats excitement occurred Fridays forecast thin layer four-day weather sandwich However based encouraging figures light winds aver age soaring conditions shutoff time day set 600 pm Published starting time four days 1000 am Troy Lawicki group Sil ver Eagles Soaring Society Michigan first course 1045 Several others followed logged very short flights Further attempts went way until about two oclock shortly after 17 Sailplanes air same time sight Nine working same thermal see 14-foot beau ties gracing same sky Contest Direc tor s reward time frame between 219 228 13 teams entered course included nine top 10 last years event test both Sailplane pilots skills purest form No gimmicks no trick launch equip ment no bad luck due bad draw can claimed protested against year con testants furnished own winches could launch exactly wanted Once air strategy overshadows luck ship capable bridging thermals moderate altitude trade off higher altitude because youll able cover ground once higher what about winds higher altitudes plowed fields plot ted course map just case need seek out hoping thermal being generated need day nature threw just crumb contestants way didnt last long Among gaggle 13 entered course about same time Jim Boh mer MOSS club group won event last year year retrieved model after 33 miles Skip Miller FAST first ever finish course official time managed 56-mile run relaunched logged 99 best effort during meet Six teams made about 20-mile mark Among Ken Bates Kurt Bak Mike McIntyre Ken Shaw MRCS Ann Abbor MI some six teams played lift hopes altitude before stretching down long southern course Bates left pack about half altitude highest plane group looked though wrong move After losing altitude down treetop height plowed field gave plane nudge upward Bates played thermal out new life made around south side course flew westward northbound forecast winds increased south provided team tailwind last half run Meanwhile south erly heading western leg coming down MRCS suddently course themselves Radio reports gave teams progress no question team con ditions favorable completing course question could beat clock well past three-hour mark air 600 pm shutoff nearing Passing last radio check point became very doubtful whether could finish course time rules state distance flown time shutdown will official distance time less seven minutes go still six miles flown radio reports made exciting Saturday sporting event drama moon launch countdown precisely 175930 official watches MRCS touched down com pleting 76 km1472 mile course three hours 32 minutes second time two years Bates company conquered Soarings greatest challenge also second time used makeshift bird year used wing very old Super Esprit parts other planes team Stan Watson Jim Slater Eric Stenson Dave Haertelrepresenting 4-STROKE ENGINE SALE COMPARE & SAVE Os FS 408950 OSFS6012500 OS FS 7514500 OS ES 120T34900 ENYA4O-4C12950 ENYA6O-4C14950 ENYA9O-4C18950 SAITO 308450 SAITO 40-Il9950 SAITO4510950 SAITO 90T29950 TERMS Prepaid check money order Include $250 UPS street address Calif residents add 6% sates tax No credit cards please Allow 2 weeks delivery REDWOOD hobby imports PO BOX 6171 SANTA ROSA CALIF 95401 Sublect stock hand 140 Model Aviation
Edition: Model Aviation - 1983/10
Page Numbers: 40, 41, 42, 132, 133, 136, 137, 140
Cutaway electric motor models Tom Chipley shows parts will help follow authors text heart system Electrics CAN SET SCREW ADAP FRONT BEARING about FIELD MAGNETS END BELLREAR BRUSHESBEARING 3 N\~ COMMUTATOR_ ARMATURE_CAPACITOR V. POLARIZED CONNECTOR w w w heart electric-powered airplane motor chapter describes whats motor provides some tips successful operation long useful life dont have know about elec tric motors enjoy flying Electrics youll ahead crowd Part 2 U Bob Kopski LAST MONTH highlighted features characteristics electric power noting advantages disadvantages showing varity electric-powered models broad range applicability con venience fun aspects relatively new form model power emphasized So much convincing Now does modeler average skill make hap pen Lets start getting know about electric motors sense knowledge about conventional gas power reciprocating enginesoften comes naturally feel comfortable familiar family car lawnmower engines Carburetor word unheard dinner table commutator thats bit unfamiliar unknown can bit scary purpose installment help feel comfortable electric motors describing some basics Ill get detail can use confidence Well cover some things should some things shouldnt may few things didnt know should Some things may seem necessary get started will surely help keep going Ill try make simple easy follow minimum heavy tech nical good dose plus plenty tidbits collected other single publication know Ill try arrange convenient sections can skip around interest need dictates easy future reference 1 Whats motor sections can skip over still start fly model other hand little bit information may help feel lot confident about subject because youll familiar what makes em hummmmmmm small direct current DC electric motors permanent magnet type used example batteryoperated toys applicances some auto accessories electric-powered air planes motors usually have two pieces strong magnetic material 40 Model Aviation motors typical readily available US modelers upper Astro 10 lower Leisure LT-50 Both have connecting wires convenient plugs well brush capacitors visible Leisure However have different kind prop adaptor i SQ Left Two kinds rear-end bells brushes connector cord has non-replaceable brushes well worn arms spring material Look closely may notice has no bearingthe result hard landing other rear-end assembly has replaceable brushes ball bearings armature shaft Coil springs provide bruah pressure left rear-end bell early Leisure motor other current Leisure LT-50 Center Two motor housings magnets intact left low-cost motor having front-end bell part drawn motor can Visible bearing two boles mounting screws two vent holes other housing has removable bells both ends Right Two typical armatures windings stripped oft clearly shows three poles poles made stacked thin iron laminations Drill marks top-most pole balancing final armature assembly Windings commutator visible left armature Left Hatch flipped back its tape hinge reveals rear cobalt 05 motor connector charging jack Look carefully might see brush dust inside fuselage hatch Note smooth nose block Persuader Acrobatic model Right Props 6 9-in diameter various prop adaptors held armature shafts setscrews pressed-on adaptors dont easily come off arent used much anymore Props may have drilled fit adaptors After boring balance achieve peak smoothness fixed opposite other inside round iron can housing field poles form strong magnetic field inside can armature assembly rotate within ends housing capped end bells ai least can usually removed Sometimes end simply part formed motor can end bells have centered bearings either bushing type ball type support armature shaft armature shaft holds stack thin iron laminations shaped form poles always odd number poles usually three seven Most small motors have three unmagnetized armature poles wound insulated copper wire. windings connected another part armature shaft called commutator commutator round insulator metal segments outer surface number segments equals number armature poles really rotary switch sequentially connects power source armature windings done through two spring-loaded sliding con tacts brushes ride ihe commutator segments armature assembly rotates two brushes normally mounted rear-end bell insulated other motor housing commutator segments bi-ushes carefully positioned relative armature poles housing field magnets respectively voltage applied external brush connections some ar mature polcs become electromagnetized just right place pushed others pulled field magnets forces cause armature begin rotating As commutator rotates new position power directed switched next winding set new poles will now pushed pulled stationary magnetic field timing characteristic similar auto engine sures proper sequential firing cylin ders As action continues motor armature spins seemingly smooth con tinuous rotationeven though electrical current being switched winding set next rapidly creating instant elec tromagnets out otherwise plain iron armature poles Start-up current can very heavy surge Once spinning however unloaded motor normally draws relatively little cur rent because sniall amounts electri cal power required overcome bear ing brush friction some other small power losses mechanical load applied motor shaft like propeller motor has work consequently electrical input power must increase Putting another way cant get something nothing Some examples illustrate will given later tn application motor acts convert extra electrical power input propeller thrust 2 Motors model use make motor suited model use some fea tures added basic machinery de scribed above Lets look impor tant ones some detail touch several others Prop adaptor fitting armature shaft extflding front motor either press-fitted held io shaft setscrew prefer shafts small flat setscrew get good bite onto prop adaptor may have threaded extension oh Which prop placed held washer nutvery similar gas engines prop adaptor may have inside thread prop held screw washer similar some small glow engines latter case multiple washers may supplied allow prop screw accept range prop hub thicknesses change screw length Its probably October 1983 41 5-40 thread almost impossible find anywhere B Motor mount Some method niounting motor needed Most motors have two four threaded holes frontend bell can used partially se cure motor Some motors have metal mounting clamps slip around housing form two beams similar glow engine Others have matching plastic mounts ease task installation personal preference structural motor mount 1 use part fuselage struc ture support motor often con junction aforementioned front-bell screw holes reducer mounting holes dont care slip motor tight tube type friction motor-holder popular early days Electrics Motor mounting sometimes stumbling block first-time Electric flier some proven methods will covered detail future meantime look accompanying photos get general idea C Venting thing am very big adequate venting motor During flight motor can develop significant internal heat fact properly used motor can get hot enough melt solder connections rapidly wear brushes As far Im concerned theres no such thing too much venting motor Most motors have openings front-end bell well rear vicinity brushes Vents must kept clear mounting motor provision must made motor air exit model struc ture Well see some ways future installment Ive learned hard way avoid motors no venting D Brushes etc very nice feature some motors replaceable brushes gen erally found costly and/or larger motors Brushes wear away fine dark colored brush dust exits hotor vents deposited some extent fuselage Dont worry powder harmful structure like oil Brush wear related hard work motor and/or effective venting Also brushes made differ ent materials affects wear rate lower-cost motors brush re placement possible brush wear may determining factor long motor lasts especially motor worked hard other hand once sold plane over 400 flights logged low-cost motor half original brush material remained time motor tached Continued page 132 42 Model Aviation four pictures show inside out kind structural motor mount motor mounted center pictures Astro 10 Dan Gravers sport flier named Friendly Two formers I/ Lite Ply provide support fore aft Cutout rear clearly offset right thrust obvious offset Dan has downthrust Nylon landing gear straps hold motor front former 6-32 screws front-end bell No 2 sheet-metal screws former Make cutouts round snug fit motor wrap plastic tape fixes minor misfits Two fuselage fronts having same kind structural motor mount motor slides rear through top hatch up against nylon right-angle brackets latter CyA glued 1/6. ply tube epoxied inside bored balsa block block turn glued fuselage sides carved smooth shape right fuselage has bottom skids prop-stop tubing 2 oclock spot variety motor mounts shown left plastic beam mount slips over motor housing setscrew holds tight Next structural motor mount natural part fuselage assembly third Mabuchi motor metal U-shaped clamps meet form mounting beams clamps also serve flux rings note air vents arent covered right another plastic mount radial type also held setscrew attaches cutout firewall four screws Thrust adlustments direction easy radial mount Phase Art Best Custom Screen Sportswear \~kl 4893SNu Piper Cub NATS Shirts Still Available See Bealeton VASept 17 8 18 Greenville SCSept 23 Stratford CTOct 1 FAI Championships Pensacola FLOct 10-14 Designs just come aviation designs available top quality line sportswear designs direct printno heat transfer Three color B-25. Piper Cub. Bee. P40 Warha wks kker D VII. P-3. AT-6. Christen Eagle. Pitts Special. Citabria. P47 Thunderbolt earman Curtis enny. Corsair. coaches shirtS1295TShirt$695 LadiCs TopSSSOLong Sleeve T$795 Shorts$5SSBesebell$S95 Lined JacketS2195Football$S95 Tote Bag$9SSweetshirt$950 Tire coverS1495Hooded Sweot$1495 HatS595 Wide choice colors aizesi Send $100 new illustrated Brochure Refundable First Order Name Address cityStateZip DesignSize Color now accept MasterCard & Visa TO ORDER Send check money order Shipping $1-is add 5150 Over $15 add 10% Maryland residents add 5% taxI Phase Art 17102 Earlham Ct Upper Marlboro MD 20772 1301 8433050 wings find have root rib WI little crooked have tapered fairing blocks properly now good timc fit wid root fuselage hLindy sanding block Covering may use whatever covering material desirc though highly recom mend MonoKote combination like cover bottom surfaces dark easy-to-see color cover top lighter brighter color pleases eSe Radio installation fuselage little smallonly wide servo area room two medium-size servos like Kraft KPS-14 though like small Futaba S-2t mounting two S-20s forward possible leaves little access space allows mounting switch Bulkhead F2 Snap-Lip pushrods install receiver bet dre install switch switch button sticking ward through F can lift canopy easily operate use larger servos will have mount switch dit receiver between Bulkheads F3 F4 battery compartment will take Kraft KB-4M 450 Futaba NR-4G 225 pack Flying Scooter very stable glides fairly fgst turns tightly minimum loss altitude stalling angle-of-attack fairly high Best unlike flying-stab planes easy ginner tly recommend balance point CG placed right niiddle main spar also place tow hook right CG After try way can move CG and/or tow hook wherever yov can fly best good way -Add weight nose block balkust sheet lead can buy local plumbing shop cut shape tin snips used Ii-in wing wire primarily cause /4-in brass tubing required wAs same width spars easy align together desire can shim down wing wire size %s inserting A2-in GD /6-in ID tubing inside /4-in GD /32-in ID brass tubing will provide wing little give under sharp loads Sailplane design has its advantages disadvantageshigh lift high drag low drag low lift etc No design really perfect however feel Scooter good compromise Good lift Radio Technique/Myers Continued page 39 problems thanks Al Watson Gary Wild reports kind help makes job easier really enjoy hearing fr6m folks go out get valid test data selves instead wasting time listening Know-It-AIls havent actually done anything What else caii tell potential various kinds interference still present should monitor band order know what avoid its still good idea check DFC planning contest encounter problems new RC channels re port DFC Beyond can fly new RC channels con fidence Have acquired new hobby Im slow answering letters apologize know excuses Recently bought Kaypro II Word Processor attempt catch up letters pile Frequency Committee mail among other things Up till now Ive using WW II surplus Royal KMM typewriter needs new rubber nobody stocks parts Dick Jannson says should ashamed admit three kids college time what else would expect Anyhow see Bob Aberle spending 40 hours week Frequency Committee businessnow Im trying find way get job done smaller investment time Kayproll seems help picked Kaypro LI because meets needs complete cheapest complete package local support As Ive said before about hobby items believe important have local dealer support its possible save little money going through mail Youll have make up own mind about Im knocking mailorder houses Im dogmatic about either want something isnt carried locally like Circus Radios Kalt Helicopters dont have other choice except So call somebody toll-free line want parts just really didnt buy thing start other hobby seems have effect So readers have bright ideas about get best out tool about letting know about Kaypro II runs CP/M Version 22 Kaypro II trademark Kaypro Corp 533 Stevens Ave Solana Beach CA 92075 George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 Electrics/Kopski Continued page 42 same new As brushes wear frequently wear unevenly brush will wear much rapidly other ddnt know happens bUt does alwys put two new ones As new motor always break-in new brushes allowing motor run no prop very small prop cooling about 24 hours about halfthe normal voltage Instructions some elec tric motor systems discuss some come factory break-in break-in allows new brushes wear shape commutator seat better good 132 Model Aviation WAYNE ULERYS 1/3 SCALE LASER 200 THE PLANE THAT WON THE WEST span 9825 Wing area 1615 sq 18 lbs Eight LASERS flown 1982 T0C placed top twelve. Unique easy wing construction Foam cutting equipment required Special instructions pictures wing assembly Fiberglass cowl wheel pants plastic canopy 6061 T-6 aluminum wing spar 2024 T-4 landing gear available Information parts plans order SASE $2000 per set rolled plans Postage paid t5e Continental LISA Wayne Ulery 2564 Fox Hollow Rd Springfield Ohio 45502 both mechanical electrical reasons Commutators much harder mate rial brushes nomally wear away However brushes al lowed wear down completely metal brush arm brush springs begin ride commutator will wear tt will probably become scored motor performance will decline electrical noise due ex cessive sparking likely commutator could permanently ruined avoid problem best look brushes occasionally especially re placeable Some visible through bent holes disassembly necessary inspection Others easily removed exter nally brush holders unscrewing caps Handle brushes carefully cleanly replace same way came out Ive seen other problems brushcommutator area Some motors may begin display noticeable performance drop erratic running no apparent reason often associated excessive brush sparking possibly radio glitches may due inadequate brush pressure though brushes show little wear brush arms spring material lower-cost motors become overheated due motor being overworked some other reson may lose some tension Another effect high heat can com mutator distortion commutator gets out round brush bounce occurs case brushes excellent condition cant job fact Ive seen happen motors no way overworked commutator defective start can seen during break-in unloaded unpropped motor runs erratically can actually feel rotational irregulatiry hand commutator out round lay running motor table can watch twitch Use warranty card should motor defective received Both conditions inadequate brush pressure out-of-round com mutator can appreciated better apply ing some light pressure either brush through vent hole toothpick motor speed picks up smooths out no ticeably chances prob lems exists have relatively new cobalt motor has treated considerable care two occasions far performance suddenly dropped off Aerobatics model just wouldnt its usual tricks Close inspection revealed nothing unusual brushes commutator looked good battery pack etc normal brushes cobalt motor ride square brush guide tubes have coil springs brush pressure Upon re assembling brushes same brush same holder same orientation motor its old self again same thing happened visitor last years Electric Fly guess brushes become little snug guides pressure effectively reduced Perhaps some brush dust clogs guide bit Anyway removing brushes wiping tissue cleaning guide tube dry pipe cleaner does trick sure handle brushes carefully keep fingers off avoid possible con tamination Sometimes above conditions apply symptoms similar motor has run hard resulting high brush heat some brush material may smeared heavily commutator sur face prevent good electrical contact Try cure Take prop off run motor normal battery pack two three minutes Replace prop tached rpm before after may see noticeable improvement possible recommend making note motor/battery performance new after break-in generally note rpm particular prop size make battery voltage time Later theres question about performance data can compared unlike rangechecking radio rechecking under same conditions later date crash hard bump prop prop adaptor can easily bend armature shaft resulting obvious wobble vi bration Sometimes shaft can straight ened prop will run true armature may still wobble due shaft bend behind front bearing also causes brush bounce erratic running Like brushes some higher-quality motors have armature replacements can bought cases such above recourse unless youre ma chine work Sometimes impact can severe enough rear-end bell and/or bearing break get pushed out rearward-driven armature assembly Ive seen few crankshafts glow engines come through backplate too careful use flexible nylon prop and/or prop stop stop prop horizontal position minimize such problems E Bearings Electric motors models have either sleeve bearings ball bearings Usually sleeve bearings selflubricating self-centering motor 400 hts type new owner flew past 500 flights Finally bearing wear caused much noise embarrassed replaced motor about 12 dollars Thats about cost gallon you-know-what Ball bearings found larger and/or costly motors What kind un pleasant contradiction costly motor ball bearings non-replaceable brushes little like car nonreplaceable tires Given choice Im content sleeve bearings small motors Im convinced balls worth added cost kind flying may afford com petitive edge series flying addressed fun sport flying Whatever bearing type never add lu Con tinued page 136 THIS FUEL FEATURES RUST PREVENTION AGENTS ODETERGENTS OLUBRICATION WITH HIGH FLASH POINTS WETHNG AGENTS FOR MORE EFFICIENT AND DEPENDABLE FUEL FLOW OANTI-FOAMING AGENTS TO PREVENT LEAN RUNS KEEPS YOUR ENGINE RUNNING COOL OAN ODORLESS HIGHLY REFINED FUEL CHILDPROOF LIDS Available FAI 5 10 15 25 & 40% Nitro-Methane Contents Formulated synthetic lubricants Also available castor DEALERS WANTED DOMESTIC & OVERSEAS WE EXPORT competition tuel fast becoming THE CHOICE top protesonals ot tirst ro cash product Contact us price structures ordering information Manufacturers Major Brand Distilbutors Model Engines Kits Radios Accessones SUPER K Fuels brand KINGS RADIO CONTROL HOBBIES INTERNATIONAL 3960 West 16 Ave Hlaleah Florida 33012 305 557-2024 October 1983 133 1r specially formulated chemically balanced fuel top petformance minimum engine wear weather condition Electrics/Kopski Continued page 133 brication drop oil might find its way onto commutator surface brush material Thats end Im told F Other motor features Some other things make motor better use model aircraft often include wire set suitable polarized connector terminals easy connections Usually ca pacitors wired brush terminals help suppress electrical noise may otherwise interfere RC operation High-temperature insulation epoxy coat ing windings lacing wires commutator connections keep everything place good features too motors have finely finished bal anced armatures assure smooth vibrationfree operation Motors may have neutral tim ing turn equally well either direction others may have offset timing maximize performance normal di rection propeller use Some motors pack higher power han dling capability small case through use costly very high strength field mag nets such samarium cobalt material feature adds big bucks motor price armature shafts bend just easily sure pay particular attention land ing German Keller motor available flux rings metal bands slip over outside motor can make metal thicker Without case rela tively thin motor works best small props high revs case heavied-up rings motor develps higher torque turn larger props efficiently lower rpm Its like having variety motors 3 Motor size often subject much confusion beginners Its presently cause much ado modeling indus try Opinions vary to specify size classes Eventually some standards will emerge AMA SEAM Society Electric Aircraft Modelers other interested parties sort out best options necessarily simple task Un like gas engine typically char acterized its displacement cubic inches several candidate ways characterize classify electric motors way would measure physical size such armature perhaps overall motor weight Another way de scribe battery instead motor size class determined number and/or kind cells motor battery method used Europe FAt events will interesting see settled Eventually will important have some size designations allow orderly inevitable evolution competitive Elec tric events folks arent quite ready competition yet just trying get started series intended help As youll see some standards would very big help too First lets look what motor size has historically meant largest variety motors country have descriptions sound like gas engine sizes ex ample popular motor size 05 has come mean motor would swing same size prop about same rpm typical glow counterpart Thus 05 example would probably use 6-in diameter 4-in pitch prop would turn prop about same speed glow 049s Similarly electric IS might swine 8-4 prop sounds simple enough isnt Things changing Electric evolving some associated growing pains joys cobalt 05 example can easily out-power 049 glow engineand swing much heftier prop too Its really good ol 05 Other changes occurring too all-time favorites so-called 075 its old self anymore Despite same nomenclature catalog number windings now different long-developed familiarity goes out window least deserves new part number above given purpose confusing Rather illustrates creasine need size class standards reminds us present dynamics Builders Get f Better Start Season Using KIN-CRAFT Quality Line Polyester Resins Micro-Balloon Air-O-Fill Gloves Protective Fiberglass Cloth & Tapes 6 oz Cloth 1 4 & 6 Tapes Custom Cut Cloth Any Length Sandable Primers Thinner Accessories also Dust Masks Gator Grip Contact Cement Applicator Kits Engine Cleaner Oil Kits 2u Ii tj Ilobby Prod U IS Send self-addressed stamped envelope free catalogue discounts Dealer Distributor Inquiries Invited Kin-Craft Mig Ri 2 Box 481E Ashland KY 41101 606 928-4763 136 Model Aviation SUPERwings DIVISION oF HI JOHNSON MODEL PRODUCTS 11015 GLENOAKS BLVD PACOIMA CA 91331 SAILPLANE COMPONENTS CREATE YOUR OWN SUPER GLIDER WING FOAM CORES Floater Thermal & Slope FUSELAGES LUSTROLEEN 2 Meter Standard Open & Scale STAB FOAM CORES Rudder & Fin Cores COVERING MATERIALS White skin & Lustroleen WING RODS Wing Tongue Kits FOR HI JOHNSONS PORTFOLIO PRICE SHEET & ORDER FORM about sailplane construction & design using foam & plastic SEND $250 CHECK OR MO CA RES ADD SALES TAX AMA Clubs Giant Scalers Save 30%Order Direct Buckeye Balsa supplies AAA quality balsa certified aircraft plywood fine kits Aero Composites Double C Mfg Fliteglas Models Fourmost Products Kitty Hawk Models Dave Platt Precision Built Models R/C Kits Mfg VK ModIs Bob Dively Model Aircraft hobby shops Send $1 catalog Price applied first order Minimum Net Order $50 No sh pprng COD charges 216 533 3607 P0 Box 174 Canfield OH 44406 ALL SKEET ONE PIECE AAA GRADE KILN DRIED SANDED TO CLOSE TOLERANCES PED 100% Balsa Sheets36Light 46lb361/8 x 3453/16 sq 173/8 x 11/246 1/16 x 2331/16 x 3491/16 x 4481/4 sq 261/2 x 270 3/32 x 2403/32 x 3563/32x4561/4x3/8 30 1/8 x 2431/8 x 3671/8 x 4663/8 sq 37BalsaTriangles 3/16 x 2493/16 x 376 Sticks 6 1/4 x 2561/4 x 385 ched 40%1/4 x 1/425 3/8 x 3115 ets 423/8 x 3/830 1/16x3371/2 x 31393/32 x 4100 W1/2x1/235 3/32 x 3441/8 x 4108Basswood h Pine3/4x3/445 1/8 x 354BalsaSheets483/16x4120 cks For1 xl55 3/16 x 3621/16 x 3491/4 x 4131 Scale 1/4 x 3733/32 x 358Balsa Sticks36Lite Ply48 5/16x3851/8x3 711/8 x 6150 3/8 x 3883/16 x 3 821/16 x 1/409 1/2 x 31101/4x 33/32 x 1/410Birch Dowels 361/8 x 12300 3/4x31653/8x31241/Bsq.081/8 09 1/8x1/411 3/16113Ply Birch48 1/4141/64x12525 1 x3200 1/2x3155 1/8x1/2181/32x12425 1/16 X 4581/16 x 4763/16 sq.11Sendaddressed1/16 x 12435 3/32 x 4703/32 x 41/4 sq.16 1/8ic4801/8x41/4x1/221stanipedenvelope1/8x12450 3/16 x 4933/16 x 43/8sq.27 logue 1/4x4110 1/4x4134 318x1/232listingall sizesSPlyBirch48 3/32 x 12570 3/8x41653/8x4225 1/2sq.361/8x12585 1/2 x 4225Pine Sticks36 Trailing Edge 3/16 x 12585 NEWBalsa Sheets 30 1/8 sq.13361/4 x 12600 Quarter1/16 x 331 1/8 x 1/416 1/4*132 ScaleSizes3/32x337 1/8x3/820 5/16x11/439 accept Visa Master Card personal checks COD jiandling Charge $3 pay UPS Add $2 COD $3 extra PP SPO FPO 5% tax Texas US currency relatively new area model aviation So advised dont discouraged Some day future will good ol days' Electric new Standards lacking notwithstanding series will help get flying un derstand hows whys meantime consider lonely world df few US suppliers products electric-powered flight Im sure its long lean decade dedication per severance belief future thank stalwai-ts Im convinced major chunk modeldoms future de servedly Without wouldnt reading 4 When get good stuff nearing end Part Two series know readers may getting quite anxious get building flying something Thats quite under standable lets pause put whole Electric thing perspective Its rela tively new unfamiliar mLdelers including some very astute skilled Based inquiries receive subject continues bring far questions readily available answers Now consider popular continuing columns some modeling magazines devoted conventional engines Surely things have use bug enough everyone knows about right Nope Now consider basic arti cles have seen devoted electric motors electric flight batteries electric anything elseall unanswered questions right Look another way know someone flying group whos got together Hes guy experience engines always run just right maintains equipment specialist Helicopter Scale Rubber Com bat whatever guy knows awful lot about modeling general too knows what hes doing has good un derstanding basics uses full advantage series will have plenty to' examples go along its parallel goal convey basic understanding fundamental aspects electric-powered flight time-honored method teachingbasics plus examples Some text some lab work sorta under hat youll soon easily answering understanding such questions what motor needed fly what plane what should weigh assure much flight time Soon Electric products today will become dated will specific examples based dont want series become dated want continue basic value understanding utilization whatever new better prod ucts come along have reasod able acquaintance Elec tric works will have no trouble obtaining first-time continuing success Stay us youll person has together' Electric very anxious let suggest youre following series also keep eye contemporary magazines good source suitable Electric designs have already published MA alone has three four last year articles typically include electric system information design Later series will suggest guidelines motor plane combinations will assure success Also intallation coming As mentioned Part very versatile RC design Spectra can accommo Con tinued page 140 ATTENTION ERS October 1983 137 EPOXY GLASS COWLS FOR NOSEN PICA SIO MORGAN BALSA USA PLA TT CONCEPT FLEET HOSTETLER RCM T-CRAFT SHEBER P177S & SCALE SUPER CUB POKEER O7 BOEING P72 P26 F4B2 P464 SPARROW HA WE GEE BEE MOO r MACBRIEfSS TURBULEAIT CHRISTEN EAGLE BRISIGHELLAS STAROUSTEFf II A SCALE 1381 BABY FLYBABY AIRCAMPER PILOT JUNGMANN 735 SCALE 7/4 SCALE DECATIIALON PIPER PA- TB ft OThERS WHEEL PANTS FOR CITABRIA SrAROUS TER II PIUS SKYBOLT LIBERIYSPORT CHRISTEN EAGLE PBE HAWK STEARMAN STINSON SRB MULLIGAN & OTHERS BRAZED& HEAT-TREATED WIRE GEARS&CABANES LARGE SCALE PLANS AVAILABLE Send $100 latest list supply Modelers fiberglass parts plansWrite call us T & D FIBERGLASS SPECIALTIES 30925 eLOcK GARDEN CITY Mi 48135 PHONE 313 421-6358 r Finally.. 1/3 Scale Realism lightweight highly detailed realistic pilot figure scale R/C model aircraft figure Shown 1/3 scale civilian Seated approximately 125 tall 310 mm weighs 15 ounces comes complete including instructions painting fits 1/3 scale planes including Pitts Eagle Homebuilts ORDER YOURS TODAY Produced byPrice $1995 William M Hawke$200 shipping 7148 Lasting Light Way Columbia MD 21045 Ask dealer order diredt 1/4 scale coming soon L Electrics/Kopski Continued paqe 137 date variety electric power systems planned construction article Next up Part Three will discuss pro pellers electric power motors sole function convert energy stored battery propeller thrust Im sure will amazed just what takes turn prop various props com pare prop change affects flight performance think youll find Part Three enlightening though still fundamental also graphic unique dont think thing like has published before Part Four will devoted bat teries about batteries Installations planes follow Now answer title question good stuff will continue will eventually come together promise As continue challenge series Ive come appreciate its sizeable scope very difficult write compact complete simple Introduction Elec trics regard want thank wife Wilma MA Editor Carl Wheeley Columnist Bill Winter Electric flying friends KRCHerb Dirks John Hickey Heinz Koerner Don LeGower Dan Mittenfor critiquing drafts artworks helpful sugges tions Any questions related part earlier parts series may directed SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 RC Soaring/Pruss Continued page 45 helpful may have noticed skipped Fri days activity did because thats excitement occurred Fridays forecast thin layer four-day weather sandwich However based encouraging figures light winds aver age soaring conditions shutoff time day set 600 pm Published starting time four days 1000 am Troy Lawicki group Sil ver Eagles Soaring Society Michigan first course 1045 Several others followed logged very short flights Further attempts went way until about two oclock shortly after 17 Sailplanes air same time sight Nine working same thermal see 14-foot beau ties gracing same sky Contest Direc tor s reward time frame between 219 228 13 teams entered course included nine top 10 last years event test both Sailplane pilots skills purest form No gimmicks no trick launch equip ment no bad luck due bad draw can claimed protested against year con testants furnished own winches could launch exactly wanted Once air strategy overshadows luck ship capable bridging thermals moderate altitude trade off higher altitude because youll able cover ground once higher what about winds higher altitudes plowed fields plot ted course map just case need seek out hoping thermal being generated need day nature threw just crumb contestants way didnt last long Among gaggle 13 entered course about same time Jim Boh mer MOSS club group won event last year year retrieved model after 33 miles Skip Miller FAST first ever finish course official time managed 56-mile run relaunched logged 99 best effort during meet Six teams made about 20-mile mark Among Ken Bates Kurt Bak Mike McIntyre Ken Shaw MRCS Ann Abbor MI some six teams played lift hopes altitude before stretching down long southern course Bates left pack about half altitude highest plane group looked though wrong move After losing altitude down treetop height plowed field gave plane nudge upward Bates played thermal out new life made around south side course flew westward northbound forecast winds increased south provided team tailwind last half run Meanwhile south erly heading western leg coming down MRCS suddently course themselves Radio reports gave teams progress no question team con ditions favorable completing course question could beat clock well past three-hour mark air 600 pm shutoff nearing Passing last radio check point became very doubtful whether could finish course time rules state distance flown time shutdown will official distance time less seven minutes go still six miles flown radio reports made exciting Saturday sporting event drama moon launch countdown precisely 175930 official watches MRCS touched down com pleting 76 km1472 mile course three hours 32 minutes second time two years Bates company conquered Soarings greatest challenge also second time used makeshift bird year used wing very old Super Esprit parts other planes team Stan Watson Jim Slater Eric Stenson Dave Haertelrepresenting 4-STROKE ENGINE SALE COMPARE & SAVE Os FS 408950 OSFS6012500 OS FS 7514500 OS ES 120T34900 ENYA4O-4C12950 ENYA6O-4C14950 ENYA9O-4C18950 SAITO 308450 SAITO 40-Il9950 SAITO4510950 SAITO 90T29950 TERMS Prepaid check money order Include $250 UPS street address Calif residents add 6% sates tax No credit cards please Allow 2 weeks delivery REDWOOD hobby imports PO BOX 6171 SANTA ROSA CALIF 95401 Sublect stock hand 140 Model Aviation
Edition: Model Aviation - 1983/10
Page Numbers: 40, 41, 42, 132, 133, 136, 137, 140
Cutaway electric motor models Tom Chipley shows parts will help follow authors text heart system Electrics CAN SET SCREW ADAP FRONT BEARING about FIELD MAGNETS END BELLREAR BRUSHESBEARING 3 N\~ COMMUTATOR_ ARMATURE_CAPACITOR V. POLARIZED CONNECTOR w w w heart electric-powered airplane motor chapter describes whats motor provides some tips successful operation long useful life dont have know about elec tric motors enjoy flying Electrics youll ahead crowd Part 2 U Bob Kopski LAST MONTH highlighted features characteristics electric power noting advantages disadvantages showing varity electric-powered models broad range applicability con venience fun aspects relatively new form model power emphasized So much convincing Now does modeler average skill make hap pen Lets start getting know about electric motors sense knowledge about conventional gas power reciprocating enginesoften comes naturally feel comfortable familiar family car lawnmower engines Carburetor word unheard dinner table commutator thats bit unfamiliar unknown can bit scary purpose installment help feel comfortable electric motors describing some basics Ill get detail can use confidence Well cover some things should some things shouldnt may few things didnt know should Some things may seem necessary get started will surely help keep going Ill try make simple easy follow minimum heavy tech nical good dose plus plenty tidbits collected other single publication know Ill try arrange convenient sections can skip around interest need dictates easy future reference 1 Whats motor sections can skip over still start fly model other hand little bit information may help feel lot confident about subject because youll familiar what makes em hummmmmmm small direct current DC electric motors permanent magnet type used example batteryoperated toys applicances some auto accessories electric-powered air planes motors usually have two pieces strong magnetic material 40 Model Aviation motors typical readily available US modelers upper Astro 10 lower Leisure LT-50 Both have connecting wires convenient plugs well brush capacitors visible Leisure However have different kind prop adaptor i SQ Left Two kinds rear-end bells brushes connector cord has non-replaceable brushes well worn arms spring material Look closely may notice has no bearingthe result hard landing other rear-end assembly has replaceable brushes ball bearings armature shaft Coil springs provide bruah pressure left rear-end bell early Leisure motor other current Leisure LT-50 Center Two motor housings magnets intact left low-cost motor having front-end bell part drawn motor can Visible bearing two boles mounting screws two vent holes other housing has removable bells both ends Right Two typical armatures windings stripped oft clearly shows three poles poles made stacked thin iron laminations Drill marks top-most pole balancing final armature assembly Windings commutator visible left armature Left Hatch flipped back its tape hinge reveals rear cobalt 05 motor connector charging jack Look carefully might see brush dust inside fuselage hatch Note smooth nose block Persuader Acrobatic model Right Props 6 9-in diameter various prop adaptors held armature shafts setscrews pressed-on adaptors dont easily come off arent used much anymore Props may have drilled fit adaptors After boring balance achieve peak smoothness fixed opposite other inside round iron can housing field poles form strong magnetic field inside can armature assembly rotate within ends housing capped end bells ai least can usually removed Sometimes end simply part formed motor can end bells have centered bearings either bushing type ball type support armature shaft armature shaft holds stack thin iron laminations shaped form poles always odd number poles usually three seven Most small motors have three unmagnetized armature poles wound insulated copper wire. windings connected another part armature shaft called commutator commutator round insulator metal segments outer surface number segments equals number armature poles really rotary switch sequentially connects power source armature windings done through two spring-loaded sliding con tacts brushes ride ihe commutator segments armature assembly rotates two brushes normally mounted rear-end bell insulated other motor housing commutator segments bi-ushes carefully positioned relative armature poles housing field magnets respectively voltage applied external brush connections some ar mature polcs become electromagnetized just right place pushed others pulled field magnets forces cause armature begin rotating As commutator rotates new position power directed switched next winding set new poles will now pushed pulled stationary magnetic field timing characteristic similar auto engine sures proper sequential firing cylin ders As action continues motor armature spins seemingly smooth con tinuous rotationeven though electrical current being switched winding set next rapidly creating instant elec tromagnets out otherwise plain iron armature poles Start-up current can very heavy surge Once spinning however unloaded motor normally draws relatively little cur rent because sniall amounts electri cal power required overcome bear ing brush friction some other small power losses mechanical load applied motor shaft like propeller motor has work consequently electrical input power must increase Putting another way cant get something nothing Some examples illustrate will given later tn application motor acts convert extra electrical power input propeller thrust 2 Motors model use make motor suited model use some fea tures added basic machinery de scribed above Lets look impor tant ones some detail touch several others Prop adaptor fitting armature shaft extflding front motor either press-fitted held io shaft setscrew prefer shafts small flat setscrew get good bite onto prop adaptor may have threaded extension oh Which prop placed held washer nutvery similar gas engines prop adaptor may have inside thread prop held screw washer similar some small glow engines latter case multiple washers may supplied allow prop screw accept range prop hub thicknesses change screw length Its probably October 1983 41 5-40 thread almost impossible find anywhere B Motor mount Some method niounting motor needed Most motors have two four threaded holes frontend bell can used partially se cure motor Some motors have metal mounting clamps slip around housing form two beams similar glow engine Others have matching plastic mounts ease task installation personal preference structural motor mount 1 use part fuselage struc ture support motor often con junction aforementioned front-bell screw holes reducer mounting holes dont care slip motor tight tube type friction motor-holder popular early days Electrics Motor mounting sometimes stumbling block first-time Electric flier some proven methods will covered detail future meantime look accompanying photos get general idea C Venting thing am very big adequate venting motor During flight motor can develop significant internal heat fact properly used motor can get hot enough melt solder connections rapidly wear brushes As far Im concerned theres no such thing too much venting motor Most motors have openings front-end bell well rear vicinity brushes Vents must kept clear mounting motor provision must made motor air exit model struc ture Well see some ways future installment Ive learned hard way avoid motors no venting D Brushes etc very nice feature some motors replaceable brushes gen erally found costly and/or larger motors Brushes wear away fine dark colored brush dust exits hotor vents deposited some extent fuselage Dont worry powder harmful structure like oil Brush wear related hard work motor and/or effective venting Also brushes made differ ent materials affects wear rate lower-cost motors brush re placement possible brush wear may determining factor long motor lasts especially motor worked hard other hand once sold plane over 400 flights logged low-cost motor half original brush material remained time motor tached Continued page 132 42 Model Aviation four pictures show inside out kind structural motor mount motor mounted center pictures Astro 10 Dan Gravers sport flier named Friendly Two formers I/ Lite Ply provide support fore aft Cutout rear clearly offset right thrust obvious offset Dan has downthrust Nylon landing gear straps hold motor front former 6-32 screws front-end bell No 2 sheet-metal screws former Make cutouts round snug fit motor wrap plastic tape fixes minor misfits Two fuselage fronts having same kind structural motor mount motor slides rear through top hatch up against nylon right-angle brackets latter CyA glued 1/6. ply tube epoxied inside bored balsa block block turn glued fuselage sides carved smooth shape right fuselage has bottom skids prop-stop tubing 2 oclock spot variety motor mounts shown left plastic beam mount slips over motor housing setscrew holds tight Next structural motor mount natural part fuselage assembly third Mabuchi motor metal U-shaped clamps meet form mounting beams clamps also serve flux rings note air vents arent covered right another plastic mount radial type also held setscrew attaches cutout firewall four screws Thrust adlustments direction easy radial mount Phase Art Best Custom Screen Sportswear \~kl 4893SNu Piper Cub NATS Shirts Still Available See Bealeton VASept 17 8 18 Greenville SCSept 23 Stratford CTOct 1 FAI Championships Pensacola FLOct 10-14 Designs just come aviation designs available top quality line sportswear designs direct printno heat transfer Three color B-25. Piper Cub. Bee. P40 Warha wks kker D VII. P-3. AT-6. Christen Eagle. Pitts Special. Citabria. P47 Thunderbolt earman Curtis enny. Corsair. coaches shirtS1295TShirt$695 LadiCs TopSSSOLong Sleeve T$795 Shorts$5SSBesebell$S95 Lined JacketS2195Football$S95 Tote Bag$9SSweetshirt$950 Tire coverS1495Hooded Sweot$1495 HatS595 Wide choice colors aizesi Send $100 new illustrated Brochure Refundable First Order Name Address cityStateZip DesignSize Color now accept MasterCard & Visa TO ORDER Send check money order Shipping $1-is add 5150 Over $15 add 10% Maryland residents add 5% taxI Phase Art 17102 Earlham Ct Upper Marlboro MD 20772 1301 8433050 wings find have root rib WI little crooked have tapered fairing blocks properly now good timc fit wid root fuselage hLindy sanding block Covering may use whatever covering material desirc though highly recom mend MonoKote combination like cover bottom surfaces dark easy-to-see color cover top lighter brighter color pleases eSe Radio installation fuselage little smallonly wide servo area room two medium-size servos like Kraft KPS-14 though like small Futaba S-2t mounting two S-20s forward possible leaves little access space allows mounting switch Bulkhead F2 Snap-Lip pushrods install receiver bet dre install switch switch button sticking ward through F can lift canopy easily operate use larger servos will have mount switch dit receiver between Bulkheads F3 F4 battery compartment will take Kraft KB-4M 450 Futaba NR-4G 225 pack Flying Scooter very stable glides fairly fgst turns tightly minimum loss altitude stalling angle-of-attack fairly high Best unlike flying-stab planes easy ginner tly recommend balance point CG placed right niiddle main spar also place tow hook right CG After try way can move CG and/or tow hook wherever yov can fly best good way -Add weight nose block balkust sheet lead can buy local plumbing shop cut shape tin snips used Ii-in wing wire primarily cause /4-in brass tubing required wAs same width spars easy align together desire can shim down wing wire size %s inserting A2-in GD /6-in ID tubing inside /4-in GD /32-in ID brass tubing will provide wing little give under sharp loads Sailplane design has its advantages disadvantageshigh lift high drag low drag low lift etc No design really perfect however feel Scooter good compromise Good lift Radio Technique/Myers Continued page 39 problems thanks Al Watson Gary Wild reports kind help makes job easier really enjoy hearing fr6m folks go out get valid test data selves instead wasting time listening Know-It-AIls havent actually done anything What else caii tell potential various kinds interference still present should monitor band order know what avoid its still good idea check DFC planning contest encounter problems new RC channels re port DFC Beyond can fly new RC channels con fidence Have acquired new hobby Im slow answering letters apologize know excuses Recently bought Kaypro II Word Processor attempt catch up letters pile Frequency Committee mail among other things Up till now Ive using WW II surplus Royal KMM typewriter needs new rubber nobody stocks parts Dick Jannson says should ashamed admit three kids college time what else would expect Anyhow see Bob Aberle spending 40 hours week Frequency Committee businessnow Im trying find way get job done smaller investment time Kayproll seems help picked Kaypro LI because meets needs complete cheapest complete package local support As Ive said before about hobby items believe important have local dealer support its possible save little money going through mail Youll have make up own mind about Im knocking mailorder houses Im dogmatic about either want something isnt carried locally like Circus Radios Kalt Helicopters dont have other choice except So call somebody toll-free line want parts just really didnt buy thing start other hobby seems have effect So readers have bright ideas about get best out tool about letting know about Kaypro II runs CP/M Version 22 Kaypro II trademark Kaypro Corp 533 Stevens Ave Solana Beach CA 92075 George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 Electrics/Kopski Continued page 42 same new As brushes wear frequently wear unevenly brush will wear much rapidly other ddnt know happens bUt does alwys put two new ones As new motor always break-in new brushes allowing motor run no prop very small prop cooling about 24 hours about halfthe normal voltage Instructions some elec tric motor systems discuss some come factory break-in break-in allows new brushes wear shape commutator seat better good 132 Model Aviation WAYNE ULERYS 1/3 SCALE LASER 200 THE PLANE THAT WON THE WEST span 9825 Wing area 1615 sq 18 lbs Eight LASERS flown 1982 T0C placed top twelve. Unique easy wing construction Foam cutting equipment required Special instructions pictures wing assembly Fiberglass cowl wheel pants plastic canopy 6061 T-6 aluminum wing spar 2024 T-4 landing gear available Information parts plans order SASE $2000 per set rolled plans Postage paid t5e Continental LISA Wayne Ulery 2564 Fox Hollow Rd Springfield Ohio 45502 both mechanical electrical reasons Commutators much harder mate rial brushes nomally wear away However brushes al lowed wear down completely metal brush arm brush springs begin ride commutator will wear tt will probably become scored motor performance will decline electrical noise due ex cessive sparking likely commutator could permanently ruined avoid problem best look brushes occasionally especially re placeable Some visible through bent holes disassembly necessary inspection Others easily removed exter nally brush holders unscrewing caps Handle brushes carefully cleanly replace same way came out Ive seen other problems brushcommutator area Some motors may begin display noticeable performance drop erratic running no apparent reason often associated excessive brush sparking possibly radio glitches may due inadequate brush pressure though brushes show little wear brush arms spring material lower-cost motors become overheated due motor being overworked some other reson may lose some tension Another effect high heat can com mutator distortion commutator gets out round brush bounce occurs case brushes excellent condition cant job fact Ive seen happen motors no way overworked commutator defective start can seen during break-in unloaded unpropped motor runs erratically can actually feel rotational irregulatiry hand commutator out round lay running motor table can watch twitch Use warranty card should motor defective received Both conditions inadequate brush pressure out-of-round com mutator can appreciated better apply ing some light pressure either brush through vent hole toothpick motor speed picks up smooths out no ticeably chances prob lems exists have relatively new cobalt motor has treated considerable care two occasions far performance suddenly dropped off Aerobatics model just wouldnt its usual tricks Close inspection revealed nothing unusual brushes commutator looked good battery pack etc normal brushes cobalt motor ride square brush guide tubes have coil springs brush pressure Upon re assembling brushes same brush same holder same orientation motor its old self again same thing happened visitor last years Electric Fly guess brushes become little snug guides pressure effectively reduced Perhaps some brush dust clogs guide bit Anyway removing brushes wiping tissue cleaning guide tube dry pipe cleaner does trick sure handle brushes carefully keep fingers off avoid possible con tamination Sometimes above conditions apply symptoms similar motor has run hard resulting high brush heat some brush material may smeared heavily commutator sur face prevent good electrical contact Try cure Take prop off run motor normal battery pack two three minutes Replace prop tached rpm before after may see noticeable improvement possible recommend making note motor/battery performance new after break-in generally note rpm particular prop size make battery voltage time Later theres question about performance data can compared unlike rangechecking radio rechecking under same conditions later date crash hard bump prop prop adaptor can easily bend armature shaft resulting obvious wobble vi bration Sometimes shaft can straight ened prop will run true armature may still wobble due shaft bend behind front bearing also causes brush bounce erratic running Like brushes some higher-quality motors have armature replacements can bought cases such above recourse unless youre ma chine work Sometimes impact can severe enough rear-end bell and/or bearing break get pushed out rearward-driven armature assembly Ive seen few crankshafts glow engines come through backplate too careful use flexible nylon prop and/or prop stop stop prop horizontal position minimize such problems E Bearings Electric motors models have either sleeve bearings ball bearings Usually sleeve bearings selflubricating self-centering motor 400 hts type new owner flew past 500 flights Finally bearing wear caused much noise embarrassed replaced motor about 12 dollars Thats about cost gallon you-know-what Ball bearings found larger and/or costly motors What kind un pleasant contradiction costly motor ball bearings non-replaceable brushes little like car nonreplaceable tires Given choice Im content sleeve bearings small motors Im convinced balls worth added cost kind flying may afford com petitive edge series flying addressed fun sport flying Whatever bearing type never add lu Con tinued page 136 THIS FUEL FEATURES RUST PREVENTION AGENTS ODETERGENTS OLUBRICATION WITH HIGH FLASH POINTS WETHNG AGENTS FOR MORE EFFICIENT AND DEPENDABLE FUEL FLOW OANTI-FOAMING AGENTS TO PREVENT LEAN RUNS KEEPS YOUR ENGINE RUNNING COOL OAN ODORLESS HIGHLY REFINED FUEL CHILDPROOF LIDS Available FAI 5 10 15 25 & 40% Nitro-Methane Contents Formulated synthetic lubricants Also available castor DEALERS WANTED DOMESTIC & OVERSEAS WE EXPORT competition tuel fast becoming THE CHOICE top protesonals ot tirst ro cash product Contact us price structures ordering information Manufacturers Major Brand Distilbutors Model Engines Kits Radios Accessones SUPER K Fuels brand KINGS RADIO CONTROL HOBBIES INTERNATIONAL 3960 West 16 Ave Hlaleah Florida 33012 305 557-2024 October 1983 133 1r specially formulated chemically balanced fuel top petformance minimum engine wear weather condition Electrics/Kopski Continued page 133 brication drop oil might find its way onto commutator surface brush material Thats end Im told F Other motor features Some other things make motor better use model aircraft often include wire set suitable polarized connector terminals easy connections Usually ca pacitors wired brush terminals help suppress electrical noise may otherwise interfere RC operation High-temperature insulation epoxy coat ing windings lacing wires commutator connections keep everything place good features too motors have finely finished bal anced armatures assure smooth vibrationfree operation Motors may have neutral tim ing turn equally well either direction others may have offset timing maximize performance normal di rection propeller use Some motors pack higher power han dling capability small case through use costly very high strength field mag nets such samarium cobalt material feature adds big bucks motor price armature shafts bend just easily sure pay particular attention land ing German Keller motor available flux rings metal bands slip over outside motor can make metal thicker Without case rela tively thin motor works best small props high revs case heavied-up rings motor develps higher torque turn larger props efficiently lower rpm Its like having variety motors 3 Motor size often subject much confusion beginners Its presently cause much ado modeling indus try Opinions vary to specify size classes Eventually some standards will emerge AMA SEAM Society Electric Aircraft Modelers other interested parties sort out best options necessarily simple task Un like gas engine typically char acterized its displacement cubic inches several candidate ways characterize classify electric motors way would measure physical size such armature perhaps overall motor weight Another way de scribe battery instead motor size class determined number and/or kind cells motor battery method used Europe FAt events will interesting see settled Eventually will important have some size designations allow orderly inevitable evolution competitive Elec tric events folks arent quite ready competition yet just trying get started series intended help As youll see some standards would very big help too First lets look what motor size has historically meant largest variety motors country have descriptions sound like gas engine sizes ex ample popular motor size 05 has come mean motor would swing same size prop about same rpm typical glow counterpart Thus 05 example would probably use 6-in diameter 4-in pitch prop would turn prop about same speed glow 049s Similarly electric IS might swine 8-4 prop sounds simple enough isnt Things changing Electric evolving some associated growing pains joys cobalt 05 example can easily out-power 049 glow engineand swing much heftier prop too Its really good ol 05 Other changes occurring too all-time favorites so-called 075 its old self anymore Despite same nomenclature catalog number windings now different long-developed familiarity goes out window least deserves new part number above given purpose confusing Rather illustrates creasine need size class standards reminds us present dynamics Builders Get f Better Start Season Using KIN-CRAFT Quality Line Polyester Resins Micro-Balloon Air-O-Fill Gloves Protective Fiberglass Cloth & Tapes 6 oz Cloth 1 4 & 6 Tapes Custom Cut Cloth Any Length Sandable Primers Thinner Accessories also Dust Masks Gator Grip Contact Cement Applicator Kits Engine Cleaner Oil Kits 2u Ii tj Ilobby Prod U IS Send self-addressed stamped envelope free catalogue discounts Dealer Distributor Inquiries Invited Kin-Craft Mig Ri 2 Box 481E Ashland KY 41101 606 928-4763 136 Model Aviation SUPERwings DIVISION oF HI JOHNSON MODEL PRODUCTS 11015 GLENOAKS BLVD PACOIMA CA 91331 SAILPLANE COMPONENTS CREATE YOUR OWN SUPER GLIDER WING FOAM CORES Floater Thermal & Slope FUSELAGES LUSTROLEEN 2 Meter Standard Open & Scale STAB FOAM CORES Rudder & Fin Cores COVERING MATERIALS White skin & Lustroleen WING RODS Wing Tongue Kits FOR HI JOHNSONS PORTFOLIO PRICE SHEET & ORDER FORM about sailplane construction & design using foam & plastic SEND $250 CHECK OR MO CA RES ADD SALES TAX AMA Clubs Giant Scalers Save 30%Order Direct Buckeye Balsa supplies AAA quality balsa certified aircraft plywood fine kits Aero Composites Double C Mfg Fliteglas Models Fourmost Products Kitty Hawk Models Dave Platt Precision Built Models R/C Kits Mfg VK ModIs Bob Dively Model Aircraft hobby shops Send $1 catalog Price applied first order Minimum Net Order $50 No sh pprng COD charges 216 533 3607 P0 Box 174 Canfield OH 44406 ALL SKEET ONE PIECE AAA GRADE KILN DRIED SANDED TO CLOSE TOLERANCES PED 100% Balsa Sheets36Light 46lb361/8 x 3453/16 sq 173/8 x 11/246 1/16 x 2331/16 x 3491/16 x 4481/4 sq 261/2 x 270 3/32 x 2403/32 x 3563/32x4561/4x3/8 30 1/8 x 2431/8 x 3671/8 x 4663/8 sq 37BalsaTriangles 3/16 x 2493/16 x 376 Sticks 6 1/4 x 2561/4 x 385 ched 40%1/4 x 1/425 3/8 x 3115 ets 423/8 x 3/830 1/16x3371/2 x 31393/32 x 4100 W1/2x1/235 3/32 x 3441/8 x 4108Basswood h Pine3/4x3/445 1/8 x 354BalsaSheets483/16x4120 cks For1 xl55 3/16 x 3621/16 x 3491/4 x 4131 Scale 1/4 x 3733/32 x 358Balsa Sticks36Lite Ply48 5/16x3851/8x3 711/8 x 6150 3/8 x 3883/16 x 3 821/16 x 1/409 1/2 x 31101/4x 33/32 x 1/410Birch Dowels 361/8 x 12300 3/4x31653/8x31241/Bsq.081/8 09 1/8x1/411 3/16113Ply Birch48 1/4141/64x12525 1 x3200 1/2x3155 1/8x1/2181/32x12425 1/16 X 4581/16 x 4763/16 sq.11Sendaddressed1/16 x 12435 3/32 x 4703/32 x 41/4 sq.16 1/8ic4801/8x41/4x1/221stanipedenvelope1/8x12450 3/16 x 4933/16 x 43/8sq.27 logue 1/4x4110 1/4x4134 318x1/232listingall sizesSPlyBirch48 3/32 x 12570 3/8x41653/8x4225 1/2sq.361/8x12585 1/2 x 4225Pine Sticks36 Trailing Edge 3/16 x 12585 NEWBalsa Sheets 30 1/8 sq.13361/4 x 12600 Quarter1/16 x 331 1/8 x 1/416 1/4*132 ScaleSizes3/32x337 1/8x3/820 5/16x11/439 accept Visa Master Card personal checks COD jiandling Charge $3 pay UPS Add $2 COD $3 extra PP SPO FPO 5% tax Texas US currency relatively new area model aviation So advised dont discouraged Some day future will good ol days' Electric new Standards lacking notwithstanding series will help get flying un derstand hows whys meantime consider lonely world df few US suppliers products electric-powered flight Im sure its long lean decade dedication per severance belief future thank stalwai-ts Im convinced major chunk modeldoms future de servedly Without wouldnt reading 4 When get good stuff nearing end Part Two series know readers may getting quite anxious get building flying something Thats quite under standable lets pause put whole Electric thing perspective Its rela tively new unfamiliar mLdelers including some very astute skilled Based inquiries receive subject continues bring far questions readily available answers Now consider popular continuing columns some modeling magazines devoted conventional engines Surely things have use bug enough everyone knows about right Nope Now consider basic arti cles have seen devoted electric motors electric flight batteries electric anything elseall unanswered questions right Look another way know someone flying group whos got together Hes guy experience engines always run just right maintains equipment specialist Helicopter Scale Rubber Com bat whatever guy knows awful lot about modeling general too knows what hes doing has good un derstanding basics uses full advantage series will have plenty to' examples go along its parallel goal convey basic understanding fundamental aspects electric-powered flight time-honored method teachingbasics plus examples Some text some lab work sorta under hat youll soon easily answering understanding such questions what motor needed fly what plane what should weigh assure much flight time Soon Electric products today will become dated will specific examples based dont want series become dated want continue basic value understanding utilization whatever new better prod ucts come along have reasod able acquaintance Elec tric works will have no trouble obtaining first-time continuing success Stay us youll person has together' Electric very anxious let suggest youre following series also keep eye contemporary magazines good source suitable Electric designs have already published MA alone has three four last year articles typically include electric system information design Later series will suggest guidelines motor plane combinations will assure success Also intallation coming As mentioned Part very versatile RC design Spectra can accommo Con tinued page 140 ATTENTION ERS October 1983 137 EPOXY GLASS COWLS FOR NOSEN PICA SIO MORGAN BALSA USA PLA TT CONCEPT FLEET HOSTETLER RCM T-CRAFT SHEBER P177S & SCALE SUPER CUB POKEER O7 BOEING P72 P26 F4B2 P464 SPARROW HA WE GEE BEE MOO r MACBRIEfSS TURBULEAIT CHRISTEN EAGLE BRISIGHELLAS STAROUSTEFf II A SCALE 1381 BABY FLYBABY AIRCAMPER PILOT JUNGMANN 735 SCALE 7/4 SCALE DECATIIALON PIPER PA- TB ft OThERS WHEEL PANTS FOR CITABRIA SrAROUS TER II PIUS SKYBOLT LIBERIYSPORT CHRISTEN EAGLE PBE HAWK STEARMAN STINSON SRB MULLIGAN & OTHERS BRAZED& HEAT-TREATED WIRE GEARS&CABANES LARGE SCALE PLANS AVAILABLE Send $100 latest list supply Modelers fiberglass parts plansWrite call us T & D FIBERGLASS SPECIALTIES 30925 eLOcK GARDEN CITY Mi 48135 PHONE 313 421-6358 r Finally.. 1/3 Scale Realism lightweight highly detailed realistic pilot figure scale R/C model aircraft figure Shown 1/3 scale civilian Seated approximately 125 tall 310 mm weighs 15 ounces comes complete including instructions painting fits 1/3 scale planes including Pitts Eagle Homebuilts ORDER YOURS TODAY Produced byPrice $1995 William M Hawke$200 shipping 7148 Lasting Light Way Columbia MD 21045 Ask dealer order diredt 1/4 scale coming soon L Electrics/Kopski Continued paqe 137 date variety electric power systems planned construction article Next up Part Three will discuss pro pellers electric power motors sole function convert energy stored battery propeller thrust Im sure will amazed just what takes turn prop various props com pare prop change affects flight performance think youll find Part Three enlightening though still fundamental also graphic unique dont think thing like has published before Part Four will devoted bat teries about batteries Installations planes follow Now answer title question good stuff will continue will eventually come together promise As continue challenge series Ive come appreciate its sizeable scope very difficult write compact complete simple Introduction Elec trics regard want thank wife Wilma MA Editor Carl Wheeley Columnist Bill Winter Electric flying friends KRCHerb Dirks John Hickey Heinz Koerner Don LeGower Dan Mittenfor critiquing drafts artworks helpful sugges tions Any questions related part earlier parts series may directed SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 RC Soaring/Pruss Continued page 45 helpful may have noticed skipped Fri days activity did because thats excitement occurred Fridays forecast thin layer four-day weather sandwich However based encouraging figures light winds aver age soaring conditions shutoff time day set 600 pm Published starting time four days 1000 am Troy Lawicki group Sil ver Eagles Soaring Society Michigan first course 1045 Several others followed logged very short flights Further attempts went way until about two oclock shortly after 17 Sailplanes air same time sight Nine working same thermal see 14-foot beau ties gracing same sky Contest Direc tor s reward time frame between 219 228 13 teams entered course included nine top 10 last years event test both Sailplane pilots skills purest form No gimmicks no trick launch equip ment no bad luck due bad draw can claimed protested against year con testants furnished own winches could launch exactly wanted Once air strategy overshadows luck ship capable bridging thermals moderate altitude trade off higher altitude because youll able cover ground once higher what about winds higher altitudes plowed fields plot ted course map just case need seek out hoping thermal being generated need day nature threw just crumb contestants way didnt last long Among gaggle 13 entered course about same time Jim Boh mer MOSS club group won event last year year retrieved model after 33 miles Skip Miller FAST first ever finish course official time managed 56-mile run relaunched logged 99 best effort during meet Six teams made about 20-mile mark Among Ken Bates Kurt Bak Mike McIntyre Ken Shaw MRCS Ann Abbor MI some six teams played lift hopes altitude before stretching down long southern course Bates left pack about half altitude highest plane group looked though wrong move After losing altitude down treetop height plowed field gave plane nudge upward Bates played thermal out new life made around south side course flew westward northbound forecast winds increased south provided team tailwind last half run Meanwhile south erly heading western leg coming down MRCS suddently course themselves Radio reports gave teams progress no question team con ditions favorable completing course question could beat clock well past three-hour mark air 600 pm shutoff nearing Passing last radio check point became very doubtful whether could finish course time rules state distance flown time shutdown will official distance time less seven minutes go still six miles flown radio reports made exciting Saturday sporting event drama moon launch countdown precisely 175930 official watches MRCS touched down com pleting 76 km1472 mile course three hours 32 minutes second time two years Bates company conquered Soarings greatest challenge also second time used makeshift bird year used wing very old Super Esprit parts other planes team Stan Watson Jim Slater Eric Stenson Dave Haertelrepresenting 4-STROKE ENGINE SALE COMPARE & SAVE Os FS 408950 OSFS6012500 OS FS 7514500 OS ES 120T34900 ENYA4O-4C12950 ENYA6O-4C14950 ENYA9O-4C18950 SAITO 308450 SAITO 40-Il9950 SAITO4510950 SAITO 90T29950 TERMS Prepaid check money order Include $250 UPS street address Calif residents add 6% sates tax No credit cards please Allow 2 weeks delivery REDWOOD hobby imports PO BOX 6171 SANTA ROSA CALIF 95401 Sublect stock hand 140 Model Aviation
Edition: Model Aviation - 1983/10
Page Numbers: 40, 41, 42, 132, 133, 136, 137, 140
Cutaway electric motor models Tom Chipley shows parts will help follow authors text heart system Electrics CAN SET SCREW ADAP FRONT BEARING about FIELD MAGNETS END BELLREAR BRUSHESBEARING 3 N\~ COMMUTATOR_ ARMATURE_CAPACITOR V. POLARIZED CONNECTOR w w w heart electric-powered airplane motor chapter describes whats motor provides some tips successful operation long useful life dont have know about elec tric motors enjoy flying Electrics youll ahead crowd Part 2 U Bob Kopski LAST MONTH highlighted features characteristics electric power noting advantages disadvantages showing varity electric-powered models broad range applicability con venience fun aspects relatively new form model power emphasized So much convincing Now does modeler average skill make hap pen Lets start getting know about electric motors sense knowledge about conventional gas power reciprocating enginesoften comes naturally feel comfortable familiar family car lawnmower engines Carburetor word unheard dinner table commutator thats bit unfamiliar unknown can bit scary purpose installment help feel comfortable electric motors describing some basics Ill get detail can use confidence Well cover some things should some things shouldnt may few things didnt know should Some things may seem necessary get started will surely help keep going Ill try make simple easy follow minimum heavy tech nical good dose plus plenty tidbits collected other single publication know Ill try arrange convenient sections can skip around interest need dictates easy future reference 1 Whats motor sections can skip over still start fly model other hand little bit information may help feel lot confident about subject because youll familiar what makes em hummmmmmm small direct current DC electric motors permanent magnet type used example batteryoperated toys applicances some auto accessories electric-powered air planes motors usually have two pieces strong magnetic material 40 Model Aviation motors typical readily available US modelers upper Astro 10 lower Leisure LT-50 Both have connecting wires convenient plugs well brush capacitors visible Leisure However have different kind prop adaptor i SQ Left Two kinds rear-end bells brushes connector cord has non-replaceable brushes well worn arms spring material Look closely may notice has no bearingthe result hard landing other rear-end assembly has replaceable brushes ball bearings armature shaft Coil springs provide bruah pressure left rear-end bell early Leisure motor other current Leisure LT-50 Center Two motor housings magnets intact left low-cost motor having front-end bell part drawn motor can Visible bearing two boles mounting screws two vent holes other housing has removable bells both ends Right Two typical armatures windings stripped oft clearly shows three poles poles made stacked thin iron laminations Drill marks top-most pole balancing final armature assembly Windings commutator visible left armature Left Hatch flipped back its tape hinge reveals rear cobalt 05 motor connector charging jack Look carefully might see brush dust inside fuselage hatch Note smooth nose block Persuader Acrobatic model Right Props 6 9-in diameter various prop adaptors held armature shafts setscrews pressed-on adaptors dont easily come off arent used much anymore Props may have drilled fit adaptors After boring balance achieve peak smoothness fixed opposite other inside round iron can housing field poles form strong magnetic field inside can armature assembly rotate within ends housing capped end bells ai least can usually removed Sometimes end simply part formed motor can end bells have centered bearings either bushing type ball type support armature shaft armature shaft holds stack thin iron laminations shaped form poles always odd number poles usually three seven Most small motors have three unmagnetized armature poles wound insulated copper wire. windings connected another part armature shaft called commutator commutator round insulator metal segments outer surface number segments equals number armature poles really rotary switch sequentially connects power source armature windings done through two spring-loaded sliding con tacts brushes ride ihe commutator segments armature assembly rotates two brushes normally mounted rear-end bell insulated other motor housing commutator segments bi-ushes carefully positioned relative armature poles housing field magnets respectively voltage applied external brush connections some ar mature polcs become electromagnetized just right place pushed others pulled field magnets forces cause armature begin rotating As commutator rotates new position power directed switched next winding set new poles will now pushed pulled stationary magnetic field timing characteristic similar auto engine sures proper sequential firing cylin ders As action continues motor armature spins seemingly smooth con tinuous rotationeven though electrical current being switched winding set next rapidly creating instant elec tromagnets out otherwise plain iron armature poles Start-up current can very heavy surge Once spinning however unloaded motor normally draws relatively little cur rent because sniall amounts electri cal power required overcome bear ing brush friction some other small power losses mechanical load applied motor shaft like propeller motor has work consequently electrical input power must increase Putting another way cant get something nothing Some examples illustrate will given later tn application motor acts convert extra electrical power input propeller thrust 2 Motors model use make motor suited model use some fea tures added basic machinery de scribed above Lets look impor tant ones some detail touch several others Prop adaptor fitting armature shaft extflding front motor either press-fitted held io shaft setscrew prefer shafts small flat setscrew get good bite onto prop adaptor may have threaded extension oh Which prop placed held washer nutvery similar gas engines prop adaptor may have inside thread prop held screw washer similar some small glow engines latter case multiple washers may supplied allow prop screw accept range prop hub thicknesses change screw length Its probably October 1983 41 5-40 thread almost impossible find anywhere B Motor mount Some method niounting motor needed Most motors have two four threaded holes frontend bell can used partially se cure motor Some motors have metal mounting clamps slip around housing form two beams similar glow engine Others have matching plastic mounts ease task installation personal preference structural motor mount 1 use part fuselage struc ture support motor often con junction aforementioned front-bell screw holes reducer mounting holes dont care slip motor tight tube type friction motor-holder popular early days Electrics Motor mounting sometimes stumbling block first-time Electric flier some proven methods will covered detail future meantime look accompanying photos get general idea C Venting thing am very big adequate venting motor During flight motor can develop significant internal heat fact properly used motor can get hot enough melt solder connections rapidly wear brushes As far Im concerned theres no such thing too much venting motor Most motors have openings front-end bell well rear vicinity brushes Vents must kept clear mounting motor provision must made motor air exit model struc ture Well see some ways future installment Ive learned hard way avoid motors no venting D Brushes etc very nice feature some motors replaceable brushes gen erally found costly and/or larger motors Brushes wear away fine dark colored brush dust exits hotor vents deposited some extent fuselage Dont worry powder harmful structure like oil Brush wear related hard work motor and/or effective venting Also brushes made differ ent materials affects wear rate lower-cost motors brush re placement possible brush wear may determining factor long motor lasts especially motor worked hard other hand once sold plane over 400 flights logged low-cost motor half original brush material remained time motor tached Continued page 132 42 Model Aviation four pictures show inside out kind structural motor mount motor mounted center pictures Astro 10 Dan Gravers sport flier named Friendly Two formers I/ Lite Ply provide support fore aft Cutout rear clearly offset right thrust obvious offset Dan has downthrust Nylon landing gear straps hold motor front former 6-32 screws front-end bell No 2 sheet-metal screws former Make cutouts round snug fit motor wrap plastic tape fixes minor misfits Two fuselage fronts having same kind structural motor mount motor slides rear through top hatch up against nylon right-angle brackets latter CyA glued 1/6. ply tube epoxied inside bored balsa block block turn glued fuselage sides carved smooth shape right fuselage has bottom skids prop-stop tubing 2 oclock spot variety motor mounts shown left plastic beam mount slips over motor housing setscrew holds tight Next structural motor mount natural part fuselage assembly third Mabuchi motor metal U-shaped clamps meet form mounting beams clamps also serve flux rings note air vents arent covered right another plastic mount radial type also held setscrew attaches cutout firewall four screws Thrust adlustments direction easy radial mount Phase Art Best Custom Screen Sportswear \~kl 4893SNu Piper Cub NATS Shirts Still Available See Bealeton VASept 17 8 18 Greenville SCSept 23 Stratford CTOct 1 FAI Championships Pensacola FLOct 10-14 Designs just come aviation designs available top quality line sportswear designs direct printno heat transfer Three color B-25. Piper Cub. Bee. P40 Warha wks kker D VII. P-3. AT-6. Christen Eagle. Pitts Special. Citabria. P47 Thunderbolt earman Curtis enny. Corsair. coaches shirtS1295TShirt$695 LadiCs TopSSSOLong Sleeve T$795 Shorts$5SSBesebell$S95 Lined JacketS2195Football$S95 Tote Bag$9SSweetshirt$950 Tire coverS1495Hooded Sweot$1495 HatS595 Wide choice colors aizesi Send $100 new illustrated Brochure Refundable First Order Name Address cityStateZip DesignSize Color now accept MasterCard & Visa TO ORDER Send check money order Shipping $1-is add 5150 Over $15 add 10% Maryland residents add 5% taxI Phase Art 17102 Earlham Ct Upper Marlboro MD 20772 1301 8433050 wings find have root rib WI little crooked have tapered fairing blocks properly now good timc fit wid root fuselage hLindy sanding block Covering may use whatever covering material desirc though highly recom mend MonoKote combination like cover bottom surfaces dark easy-to-see color cover top lighter brighter color pleases eSe Radio installation fuselage little smallonly wide servo area room two medium-size servos like Kraft KPS-14 though like small Futaba S-2t mounting two S-20s forward possible leaves little access space allows mounting switch Bulkhead F2 Snap-Lip pushrods install receiver bet dre install switch switch button sticking ward through F can lift canopy easily operate use larger servos will have mount switch dit receiver between Bulkheads F3 F4 battery compartment will take Kraft KB-4M 450 Futaba NR-4G 225 pack Flying Scooter very stable glides fairly fgst turns tightly minimum loss altitude stalling angle-of-attack fairly high Best unlike flying-stab planes easy ginner tly recommend balance point CG placed right niiddle main spar also place tow hook right CG After try way can move CG and/or tow hook wherever yov can fly best good way -Add weight nose block balkust sheet lead can buy local plumbing shop cut shape tin snips used Ii-in wing wire primarily cause /4-in brass tubing required wAs same width spars easy align together desire can shim down wing wire size %s inserting A2-in GD /6-in ID tubing inside /4-in GD /32-in ID brass tubing will provide wing little give under sharp loads Sailplane design has its advantages disadvantageshigh lift high drag low drag low lift etc No design really perfect however feel Scooter good compromise Good lift Radio Technique/Myers Continued page 39 problems thanks Al Watson Gary Wild reports kind help makes job easier really enjoy hearing fr6m folks go out get valid test data selves instead wasting time listening Know-It-AIls havent actually done anything What else caii tell potential various kinds interference still present should monitor band order know what avoid its still good idea check DFC planning contest encounter problems new RC channels re port DFC Beyond can fly new RC channels con fidence Have acquired new hobby Im slow answering letters apologize know excuses Recently bought Kaypro II Word Processor attempt catch up letters pile Frequency Committee mail among other things Up till now Ive using WW II surplus Royal KMM typewriter needs new rubber nobody stocks parts Dick Jannson says should ashamed admit three kids college time what else would expect Anyhow see Bob Aberle spending 40 hours week Frequency Committee businessnow Im trying find way get job done smaller investment time Kayproll seems help picked Kaypro LI because meets needs complete cheapest complete package local support As Ive said before about hobby items believe important have local dealer support its possible save little money going through mail Youll have make up own mind about Im knocking mailorder houses Im dogmatic about either want something isnt carried locally like Circus Radios Kalt Helicopters dont have other choice except So call somebody toll-free line want parts just really didnt buy thing start other hobby seems have effect So readers have bright ideas about get best out tool about letting know about Kaypro II runs CP/M Version 22 Kaypro II trademark Kaypro Corp 533 Stevens Ave Solana Beach CA 92075 George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 Electrics/Kopski Continued page 42 same new As brushes wear frequently wear unevenly brush will wear much rapidly other ddnt know happens bUt does alwys put two new ones As new motor always break-in new brushes allowing motor run no prop very small prop cooling about 24 hours about halfthe normal voltage Instructions some elec tric motor systems discuss some come factory break-in break-in allows new brushes wear shape commutator seat better good 132 Model Aviation WAYNE ULERYS 1/3 SCALE LASER 200 THE PLANE THAT WON THE WEST span 9825 Wing area 1615 sq 18 lbs Eight LASERS flown 1982 T0C placed top twelve. Unique easy wing construction Foam cutting equipment required Special instructions pictures wing assembly Fiberglass cowl wheel pants plastic canopy 6061 T-6 aluminum wing spar 2024 T-4 landing gear available Information parts plans order SASE $2000 per set rolled plans Postage paid t5e Continental LISA Wayne Ulery 2564 Fox Hollow Rd Springfield Ohio 45502 both mechanical electrical reasons Commutators much harder mate rial brushes nomally wear away However brushes al lowed wear down completely metal brush arm brush springs begin ride commutator will wear tt will probably become scored motor performance will decline electrical noise due ex cessive sparking likely commutator could permanently ruined avoid problem best look brushes occasionally especially re placeable Some visible through bent holes disassembly necessary inspection Others easily removed exter nally brush holders unscrewing caps Handle brushes carefully cleanly replace same way came out Ive seen other problems brushcommutator area Some motors may begin display noticeable performance drop erratic running no apparent reason often associated excessive brush sparking possibly radio glitches may due inadequate brush pressure though brushes show little wear brush arms spring material lower-cost motors become overheated due motor being overworked some other reson may lose some tension Another effect high heat can com mutator distortion commutator gets out round brush bounce occurs case brushes excellent condition cant job fact Ive seen happen motors no way overworked commutator defective start can seen during break-in unloaded unpropped motor runs erratically can actually feel rotational irregulatiry hand commutator out round lay running motor table can watch twitch Use warranty card should motor defective received Both conditions inadequate brush pressure out-of-round com mutator can appreciated better apply ing some light pressure either brush through vent hole toothpick motor speed picks up smooths out no ticeably chances prob lems exists have relatively new cobalt motor has treated considerable care two occasions far performance suddenly dropped off Aerobatics model just wouldnt its usual tricks Close inspection revealed nothing unusual brushes commutator looked good battery pack etc normal brushes cobalt motor ride square brush guide tubes have coil springs brush pressure Upon re assembling brushes same brush same holder same orientation motor its old self again same thing happened visitor last years Electric Fly guess brushes become little snug guides pressure effectively reduced Perhaps some brush dust clogs guide bit Anyway removing brushes wiping tissue cleaning guide tube dry pipe cleaner does trick sure handle brushes carefully keep fingers off avoid possible con tamination Sometimes above conditions apply symptoms similar motor has run hard resulting high brush heat some brush material may smeared heavily commutator sur face prevent good electrical contact Try cure Take prop off run motor normal battery pack two three minutes Replace prop tached rpm before after may see noticeable improvement possible recommend making note motor/battery performance new after break-in generally note rpm particular prop size make battery voltage time Later theres question about performance data can compared unlike rangechecking radio rechecking under same conditions later date crash hard bump prop prop adaptor can easily bend armature shaft resulting obvious wobble vi bration Sometimes shaft can straight ened prop will run true armature may still wobble due shaft bend behind front bearing also causes brush bounce erratic running Like brushes some higher-quality motors have armature replacements can bought cases such above recourse unless youre ma chine work Sometimes impact can severe enough rear-end bell and/or bearing break get pushed out rearward-driven armature assembly Ive seen few crankshafts glow engines come through backplate too careful use flexible nylon prop and/or prop stop stop prop horizontal position minimize such problems E Bearings Electric motors models have either sleeve bearings ball bearings Usually sleeve bearings selflubricating self-centering motor 400 hts type new owner flew past 500 flights Finally bearing wear caused much noise embarrassed replaced motor about 12 dollars Thats about cost gallon you-know-what Ball bearings found larger and/or costly motors What kind un pleasant contradiction costly motor ball bearings non-replaceable brushes little like car nonreplaceable tires Given choice Im content sleeve bearings small motors Im convinced balls worth added cost kind flying may afford com petitive edge series flying addressed fun sport flying Whatever bearing type never add lu Con tinued page 136 THIS FUEL FEATURES RUST PREVENTION AGENTS ODETERGENTS OLUBRICATION WITH HIGH FLASH POINTS WETHNG AGENTS FOR MORE EFFICIENT AND DEPENDABLE FUEL FLOW OANTI-FOAMING AGENTS TO PREVENT LEAN RUNS KEEPS YOUR ENGINE RUNNING COOL OAN ODORLESS HIGHLY REFINED FUEL CHILDPROOF LIDS Available FAI 5 10 15 25 & 40% Nitro-Methane Contents Formulated synthetic lubricants Also available castor DEALERS WANTED DOMESTIC & OVERSEAS WE EXPORT competition tuel fast becoming THE CHOICE top protesonals ot tirst ro cash product Contact us price structures ordering information Manufacturers Major Brand Distilbutors Model Engines Kits Radios Accessones SUPER K Fuels brand KINGS RADIO CONTROL HOBBIES INTERNATIONAL 3960 West 16 Ave Hlaleah Florida 33012 305 557-2024 October 1983 133 1r specially formulated chemically balanced fuel top petformance minimum engine wear weather condition Electrics/Kopski Continued page 133 brication drop oil might find its way onto commutator surface brush material Thats end Im told F Other motor features Some other things make motor better use model aircraft often include wire set suitable polarized connector terminals easy connections Usually ca pacitors wired brush terminals help suppress electrical noise may otherwise interfere RC operation High-temperature insulation epoxy coat ing windings lacing wires commutator connections keep everything place good features too motors have finely finished bal anced armatures assure smooth vibrationfree operation Motors may have neutral tim ing turn equally well either direction others may have offset timing maximize performance normal di rection propeller use Some motors pack higher power han dling capability small case through use costly very high strength field mag nets such samarium cobalt material feature adds big bucks motor price armature shafts bend just easily sure pay particular attention land ing German Keller motor available flux rings metal bands slip over outside motor can make metal thicker Without case rela tively thin motor works best small props high revs case heavied-up rings motor develps higher torque turn larger props efficiently lower rpm Its like having variety motors 3 Motor size often subject much confusion beginners Its presently cause much ado modeling indus try Opinions vary to specify size classes Eventually some standards will emerge AMA SEAM Society Electric Aircraft Modelers other interested parties sort out best options necessarily simple task Un like gas engine typically char acterized its displacement cubic inches several candidate ways characterize classify electric motors way would measure physical size such armature perhaps overall motor weight Another way de scribe battery instead motor size class determined number and/or kind cells motor battery method used Europe FAt events will interesting see settled Eventually will important have some size designations allow orderly inevitable evolution competitive Elec tric events folks arent quite ready competition yet just trying get started series intended help As youll see some standards would very big help too First lets look what motor size has historically meant largest variety motors country have descriptions sound like gas engine sizes ex ample popular motor size 05 has come mean motor would swing same size prop about same rpm typical glow counterpart Thus 05 example would probably use 6-in diameter 4-in pitch prop would turn prop about same speed glow 049s Similarly electric IS might swine 8-4 prop sounds simple enough isnt Things changing Electric evolving some associated growing pains joys cobalt 05 example can easily out-power 049 glow engineand swing much heftier prop too Its really good ol 05 Other changes occurring too all-time favorites so-called 075 its old self anymore Despite same nomenclature catalog number windings now different long-developed familiarity goes out window least deserves new part number above given purpose confusing Rather illustrates creasine need size class standards reminds us present dynamics Builders Get f Better Start Season Using KIN-CRAFT Quality Line Polyester Resins Micro-Balloon Air-O-Fill Gloves Protective Fiberglass Cloth & Tapes 6 oz Cloth 1 4 & 6 Tapes Custom Cut Cloth Any Length Sandable Primers Thinner Accessories also Dust Masks Gator Grip Contact Cement Applicator Kits Engine Cleaner Oil Kits 2u Ii tj Ilobby Prod U IS Send self-addressed stamped envelope free catalogue discounts Dealer Distributor Inquiries Invited Kin-Craft Mig Ri 2 Box 481E Ashland KY 41101 606 928-4763 136 Model Aviation SUPERwings DIVISION oF HI JOHNSON MODEL PRODUCTS 11015 GLENOAKS BLVD PACOIMA CA 91331 SAILPLANE COMPONENTS CREATE YOUR OWN SUPER GLIDER WING FOAM CORES Floater Thermal & Slope FUSELAGES LUSTROLEEN 2 Meter Standard Open & Scale STAB FOAM CORES Rudder & Fin Cores COVERING MATERIALS White skin & Lustroleen WING RODS Wing Tongue Kits FOR HI JOHNSONS PORTFOLIO PRICE SHEET & ORDER FORM about sailplane construction & design using foam & plastic SEND $250 CHECK OR MO CA RES ADD SALES TAX AMA Clubs Giant Scalers Save 30%Order Direct Buckeye Balsa supplies AAA quality balsa certified aircraft plywood fine kits Aero Composites Double C Mfg Fliteglas Models Fourmost Products Kitty Hawk Models Dave Platt Precision Built Models R/C Kits Mfg VK ModIs Bob Dively Model Aircraft hobby shops Send $1 catalog Price applied first order Minimum Net Order $50 No sh pprng COD charges 216 533 3607 P0 Box 174 Canfield OH 44406 ALL SKEET ONE PIECE AAA GRADE KILN DRIED SANDED TO CLOSE TOLERANCES PED 100% Balsa Sheets36Light 46lb361/8 x 3453/16 sq 173/8 x 11/246 1/16 x 2331/16 x 3491/16 x 4481/4 sq 261/2 x 270 3/32 x 2403/32 x 3563/32x4561/4x3/8 30 1/8 x 2431/8 x 3671/8 x 4663/8 sq 37BalsaTriangles 3/16 x 2493/16 x 376 Sticks 6 1/4 x 2561/4 x 385 ched 40%1/4 x 1/425 3/8 x 3115 ets 423/8 x 3/830 1/16x3371/2 x 31393/32 x 4100 W1/2x1/235 3/32 x 3441/8 x 4108Basswood h Pine3/4x3/445 1/8 x 354BalsaSheets483/16x4120 cks For1 xl55 3/16 x 3621/16 x 3491/4 x 4131 Scale 1/4 x 3733/32 x 358Balsa Sticks36Lite Ply48 5/16x3851/8x3 711/8 x 6150 3/8 x 3883/16 x 3 821/16 x 1/409 1/2 x 31101/4x 33/32 x 1/410Birch Dowels 361/8 x 12300 3/4x31653/8x31241/Bsq.081/8 09 1/8x1/411 3/16113Ply Birch48 1/4141/64x12525 1 x3200 1/2x3155 1/8x1/2181/32x12425 1/16 X 4581/16 x 4763/16 sq.11Sendaddressed1/16 x 12435 3/32 x 4703/32 x 41/4 sq.16 1/8ic4801/8x41/4x1/221stanipedenvelope1/8x12450 3/16 x 4933/16 x 43/8sq.27 logue 1/4x4110 1/4x4134 318x1/232listingall sizesSPlyBirch48 3/32 x 12570 3/8x41653/8x4225 1/2sq.361/8x12585 1/2 x 4225Pine Sticks36 Trailing Edge 3/16 x 12585 NEWBalsa Sheets 30 1/8 sq.13361/4 x 12600 Quarter1/16 x 331 1/8 x 1/416 1/4*132 ScaleSizes3/32x337 1/8x3/820 5/16x11/439 accept Visa Master Card personal checks COD jiandling Charge $3 pay UPS Add $2 COD $3 extra PP SPO FPO 5% tax Texas US currency relatively new area model aviation So advised dont discouraged Some day future will good ol days' Electric new Standards lacking notwithstanding series will help get flying un derstand hows whys meantime consider lonely world df few US suppliers products electric-powered flight Im sure its long lean decade dedication per severance belief future thank stalwai-ts Im convinced major chunk modeldoms future de servedly Without wouldnt reading 4 When get good stuff nearing end Part Two series know readers may getting quite anxious get building flying something Thats quite under standable lets pause put whole Electric thing perspective Its rela tively new unfamiliar mLdelers including some very astute skilled Based inquiries receive subject continues bring far questions readily available answers Now consider popular continuing columns some modeling magazines devoted conventional engines Surely things have use bug enough everyone knows about right Nope Now consider basic arti cles have seen devoted electric motors electric flight batteries electric anything elseall unanswered questions right Look another way know someone flying group whos got together Hes guy experience engines always run just right maintains equipment specialist Helicopter Scale Rubber Com bat whatever guy knows awful lot about modeling general too knows what hes doing has good un derstanding basics uses full advantage series will have plenty to' examples go along its parallel goal convey basic understanding fundamental aspects electric-powered flight time-honored method teachingbasics plus examples Some text some lab work sorta under hat youll soon easily answering understanding such questions what motor needed fly what plane what should weigh assure much flight time Soon Electric products today will become dated will specific examples based dont want series become dated want continue basic value understanding utilization whatever new better prod ucts come along have reasod able acquaintance Elec tric works will have no trouble obtaining first-time continuing success Stay us youll person has together' Electric very anxious let suggest youre following series also keep eye contemporary magazines good source suitable Electric designs have already published MA alone has three four last year articles typically include electric system information design Later series will suggest guidelines motor plane combinations will assure success Also intallation coming As mentioned Part very versatile RC design Spectra can accommo Con tinued page 140 ATTENTION ERS October 1983 137 EPOXY GLASS COWLS FOR NOSEN PICA SIO MORGAN BALSA USA PLA TT CONCEPT FLEET HOSTETLER RCM T-CRAFT SHEBER P177S & SCALE SUPER CUB POKEER O7 BOEING P72 P26 F4B2 P464 SPARROW HA WE GEE BEE MOO r MACBRIEfSS TURBULEAIT CHRISTEN EAGLE BRISIGHELLAS STAROUSTEFf II A SCALE 1381 BABY FLYBABY AIRCAMPER PILOT JUNGMANN 735 SCALE 7/4 SCALE DECATIIALON PIPER PA- TB ft OThERS WHEEL PANTS FOR CITABRIA SrAROUS TER II PIUS SKYBOLT LIBERIYSPORT CHRISTEN EAGLE PBE HAWK STEARMAN STINSON SRB MULLIGAN & OTHERS BRAZED& HEAT-TREATED WIRE GEARS&CABANES LARGE SCALE PLANS AVAILABLE Send $100 latest list supply Modelers fiberglass parts plansWrite call us T & D FIBERGLASS SPECIALTIES 30925 eLOcK GARDEN CITY Mi 48135 PHONE 313 421-6358 r Finally.. 1/3 Scale Realism lightweight highly detailed realistic pilot figure scale R/C model aircraft figure Shown 1/3 scale civilian Seated approximately 125 tall 310 mm weighs 15 ounces comes complete including instructions painting fits 1/3 scale planes including Pitts Eagle Homebuilts ORDER YOURS TODAY Produced byPrice $1995 William M Hawke$200 shipping 7148 Lasting Light Way Columbia MD 21045 Ask dealer order diredt 1/4 scale coming soon L Electrics/Kopski Continued paqe 137 date variety electric power systems planned construction article Next up Part Three will discuss pro pellers electric power motors sole function convert energy stored battery propeller thrust Im sure will amazed just what takes turn prop various props com pare prop change affects flight performance think youll find Part Three enlightening though still fundamental also graphic unique dont think thing like has published before Part Four will devoted bat teries about batteries Installations planes follow Now answer title question good stuff will continue will eventually come together promise As continue challenge series Ive come appreciate its sizeable scope very difficult write compact complete simple Introduction Elec trics regard want thank wife Wilma MA Editor Carl Wheeley Columnist Bill Winter Electric flying friends KRCHerb Dirks John Hickey Heinz Koerner Don LeGower Dan Mittenfor critiquing drafts artworks helpful sugges tions Any questions related part earlier parts series may directed SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 RC Soaring/Pruss Continued page 45 helpful may have noticed skipped Fri days activity did because thats excitement occurred Fridays forecast thin layer four-day weather sandwich However based encouraging figures light winds aver age soaring conditions shutoff time day set 600 pm Published starting time four days 1000 am Troy Lawicki group Sil ver Eagles Soaring Society Michigan first course 1045 Several others followed logged very short flights Further attempts went way until about two oclock shortly after 17 Sailplanes air same time sight Nine working same thermal see 14-foot beau ties gracing same sky Contest Direc tor s reward time frame between 219 228 13 teams entered course included nine top 10 last years event test both Sailplane pilots skills purest form No gimmicks no trick launch equip ment no bad luck due bad draw can claimed protested against year con testants furnished own winches could launch exactly wanted Once air strategy overshadows luck ship capable bridging thermals moderate altitude trade off higher altitude because youll able cover ground once higher what about winds higher altitudes plowed fields plot ted course map just case need seek out hoping thermal being generated need day nature threw just crumb contestants way didnt last long Among gaggle 13 entered course about same time Jim Boh mer MOSS club group won event last year year retrieved model after 33 miles Skip Miller FAST first ever finish course official time managed 56-mile run relaunched logged 99 best effort during meet Six teams made about 20-mile mark Among Ken Bates Kurt Bak Mike McIntyre Ken Shaw MRCS Ann Abbor MI some six teams played lift hopes altitude before stretching down long southern course Bates left pack about half altitude highest plane group looked though wrong move After losing altitude down treetop height plowed field gave plane nudge upward Bates played thermal out new life made around south side course flew westward northbound forecast winds increased south provided team tailwind last half run Meanwhile south erly heading western leg coming down MRCS suddently course themselves Radio reports gave teams progress no question team con ditions favorable completing course question could beat clock well past three-hour mark air 600 pm shutoff nearing Passing last radio check point became very doubtful whether could finish course time rules state distance flown time shutdown will official distance time less seven minutes go still six miles flown radio reports made exciting Saturday sporting event drama moon launch countdown precisely 175930 official watches MRCS touched down com pleting 76 km1472 mile course three hours 32 minutes second time two years Bates company conquered Soarings greatest challenge also second time used makeshift bird year used wing very old Super Esprit parts other planes team Stan Watson Jim Slater Eric Stenson Dave Haertelrepresenting 4-STROKE ENGINE SALE COMPARE & SAVE Os FS 408950 OSFS6012500 OS FS 7514500 OS ES 120T34900 ENYA4O-4C12950 ENYA6O-4C14950 ENYA9O-4C18950 SAITO 308450 SAITO 40-Il9950 SAITO4510950 SAITO 90T29950 TERMS Prepaid check money order Include $250 UPS street address Calif residents add 6% sates tax No credit cards please Allow 2 weeks delivery REDWOOD hobby imports PO BOX 6171 SANTA ROSA CALIF 95401 Sublect stock hand 140 Model Aviation
Edition: Model Aviation - 1983/10
Page Numbers: 40, 41, 42, 132, 133, 136, 137, 140
Cutaway electric motor models Tom Chipley shows parts will help follow authors text heart system Electrics CAN SET SCREW ADAP FRONT BEARING about FIELD MAGNETS END BELLREAR BRUSHESBEARING 3 N\~ COMMUTATOR_ ARMATURE_CAPACITOR V. POLARIZED CONNECTOR w w w heart electric-powered airplane motor chapter describes whats motor provides some tips successful operation long useful life dont have know about elec tric motors enjoy flying Electrics youll ahead crowd Part 2 U Bob Kopski LAST MONTH highlighted features characteristics electric power noting advantages disadvantages showing varity electric-powered models broad range applicability con venience fun aspects relatively new form model power emphasized So much convincing Now does modeler average skill make hap pen Lets start getting know about electric motors sense knowledge about conventional gas power reciprocating enginesoften comes naturally feel comfortable familiar family car lawnmower engines Carburetor word unheard dinner table commutator thats bit unfamiliar unknown can bit scary purpose installment help feel comfortable electric motors describing some basics Ill get detail can use confidence Well cover some things should some things shouldnt may few things didnt know should Some things may seem necessary get started will surely help keep going Ill try make simple easy follow minimum heavy tech nical good dose plus plenty tidbits collected other single publication know Ill try arrange convenient sections can skip around interest need dictates easy future reference 1 Whats motor sections can skip over still start fly model other hand little bit information may help feel lot confident about subject because youll familiar what makes em hummmmmmm small direct current DC electric motors permanent magnet type used example batteryoperated toys applicances some auto accessories electric-powered air planes motors usually have two pieces strong magnetic material 40 Model Aviation motors typical readily available US modelers upper Astro 10 lower Leisure LT-50 Both have connecting wires convenient plugs well brush capacitors visible Leisure However have different kind prop adaptor i SQ Left Two kinds rear-end bells brushes connector cord has non-replaceable brushes well worn arms spring material Look closely may notice has no bearingthe result hard landing other rear-end assembly has replaceable brushes ball bearings armature shaft Coil springs provide bruah pressure left rear-end bell early Leisure motor other current Leisure LT-50 Center Two motor housings magnets intact left low-cost motor having front-end bell part drawn motor can Visible bearing two boles mounting screws two vent holes other housing has removable bells both ends Right Two typical armatures windings stripped oft clearly shows three poles poles made stacked thin iron laminations Drill marks top-most pole balancing final armature assembly Windings commutator visible left armature Left Hatch flipped back its tape hinge reveals rear cobalt 05 motor connector charging jack Look carefully might see brush dust inside fuselage hatch Note smooth nose block Persuader Acrobatic model Right Props 6 9-in diameter various prop adaptors held armature shafts setscrews pressed-on adaptors dont easily come off arent used much anymore Props may have drilled fit adaptors After boring balance achieve peak smoothness fixed opposite other inside round iron can housing field poles form strong magnetic field inside can armature assembly rotate within ends housing capped end bells ai least can usually removed Sometimes end simply part formed motor can end bells have centered bearings either bushing type ball type support armature shaft armature shaft holds stack thin iron laminations shaped form poles always odd number poles usually three seven Most small motors have three unmagnetized armature poles wound insulated copper wire. windings connected another part armature shaft called commutator commutator round insulator metal segments outer surface number segments equals number armature poles really rotary switch sequentially connects power source armature windings done through two spring-loaded sliding con tacts brushes ride ihe commutator segments armature assembly rotates two brushes normally mounted rear-end bell insulated other motor housing commutator segments bi-ushes carefully positioned relative armature poles housing field magnets respectively voltage applied external brush connections some ar mature polcs become electromagnetized just right place pushed others pulled field magnets forces cause armature begin rotating As commutator rotates new position power directed switched next winding set new poles will now pushed pulled stationary magnetic field timing characteristic similar auto engine sures proper sequential firing cylin ders As action continues motor armature spins seemingly smooth con tinuous rotationeven though electrical current being switched winding set next rapidly creating instant elec tromagnets out otherwise plain iron armature poles Start-up current can very heavy surge Once spinning however unloaded motor normally draws relatively little cur rent because sniall amounts electri cal power required overcome bear ing brush friction some other small power losses mechanical load applied motor shaft like propeller motor has work consequently electrical input power must increase Putting another way cant get something nothing Some examples illustrate will given later tn application motor acts convert extra electrical power input propeller thrust 2 Motors model use make motor suited model use some fea tures added basic machinery de scribed above Lets look impor tant ones some detail touch several others Prop adaptor fitting armature shaft extflding front motor either press-fitted held io shaft setscrew prefer shafts small flat setscrew get good bite onto prop adaptor may have threaded extension oh Which prop placed held washer nutvery similar gas engines prop adaptor may have inside thread prop held screw washer similar some small glow engines latter case multiple washers may supplied allow prop screw accept range prop hub thicknesses change screw length Its probably October 1983 41 5-40 thread almost impossible find anywhere B Motor mount Some method niounting motor needed Most motors have two four threaded holes frontend bell can used partially se cure motor Some motors have metal mounting clamps slip around housing form two beams similar glow engine Others have matching plastic mounts ease task installation personal preference structural motor mount 1 use part fuselage struc ture support motor often con junction aforementioned front-bell screw holes reducer mounting holes dont care slip motor tight tube type friction motor-holder popular early days Electrics Motor mounting sometimes stumbling block first-time Electric flier some proven methods will covered detail future meantime look accompanying photos get general idea C Venting thing am very big adequate venting motor During flight motor can develop significant internal heat fact properly used motor can get hot enough melt solder connections rapidly wear brushes As far Im concerned theres no such thing too much venting motor Most motors have openings front-end bell well rear vicinity brushes Vents must kept clear mounting motor provision must made motor air exit model struc ture Well see some ways future installment Ive learned hard way avoid motors no venting D Brushes etc very nice feature some motors replaceable brushes gen erally found costly and/or larger motors Brushes wear away fine dark colored brush dust exits hotor vents deposited some extent fuselage Dont worry powder harmful structure like oil Brush wear related hard work motor and/or effective venting Also brushes made differ ent materials affects wear rate lower-cost motors brush re placement possible brush wear may determining factor long motor lasts especially motor worked hard other hand once sold plane over 400 flights logged low-cost motor half original brush material remained time motor tached Continued page 132 42 Model Aviation four pictures show inside out kind structural motor mount motor mounted center pictures Astro 10 Dan Gravers sport flier named Friendly Two formers I/ Lite Ply provide support fore aft Cutout rear clearly offset right thrust obvious offset Dan has downthrust Nylon landing gear straps hold motor front former 6-32 screws front-end bell No 2 sheet-metal screws former Make cutouts round snug fit motor wrap plastic tape fixes minor misfits Two fuselage fronts having same kind structural motor mount motor slides rear through top hatch up against nylon right-angle brackets latter CyA glued 1/6. ply tube epoxied inside bored balsa block block turn glued fuselage sides carved smooth shape right fuselage has bottom skids prop-stop tubing 2 oclock spot variety motor mounts shown left plastic beam mount slips over motor housing setscrew holds tight Next structural motor mount natural part fuselage assembly third Mabuchi motor metal U-shaped clamps meet form mounting beams clamps also serve flux rings note air vents arent covered right another plastic mount radial type also held setscrew attaches cutout firewall four screws Thrust adlustments direction easy radial mount Phase Art Best Custom Screen Sportswear \~kl 4893SNu Piper Cub NATS Shirts Still Available See Bealeton VASept 17 8 18 Greenville SCSept 23 Stratford CTOct 1 FAI Championships Pensacola FLOct 10-14 Designs just come aviation designs available top quality line sportswear designs direct printno heat transfer Three color B-25. Piper Cub. Bee. P40 Warha wks kker D VII. P-3. AT-6. Christen Eagle. Pitts Special. Citabria. P47 Thunderbolt earman Curtis enny. Corsair. coaches shirtS1295TShirt$695 LadiCs TopSSSOLong Sleeve T$795 Shorts$5SSBesebell$S95 Lined JacketS2195Football$S95 Tote Bag$9SSweetshirt$950 Tire coverS1495Hooded Sweot$1495 HatS595 Wide choice colors aizesi Send $100 new illustrated Brochure Refundable First Order Name Address cityStateZip DesignSize Color now accept MasterCard & Visa TO ORDER Send check money order Shipping $1-is add 5150 Over $15 add 10% Maryland residents add 5% taxI Phase Art 17102 Earlham Ct Upper Marlboro MD 20772 1301 8433050 wings find have root rib WI little crooked have tapered fairing blocks properly now good timc fit wid root fuselage hLindy sanding block Covering may use whatever covering material desirc though highly recom mend MonoKote combination like cover bottom surfaces dark easy-to-see color cover top lighter brighter color pleases eSe Radio installation fuselage little smallonly wide servo area room two medium-size servos like Kraft KPS-14 though like small Futaba S-2t mounting two S-20s forward possible leaves little access space allows mounting switch Bulkhead F2 Snap-Lip pushrods install receiver bet dre install switch switch button sticking ward through F can lift canopy easily operate use larger servos will have mount switch dit receiver between Bulkheads F3 F4 battery compartment will take Kraft KB-4M 450 Futaba NR-4G 225 pack Flying Scooter very stable glides fairly fgst turns tightly minimum loss altitude stalling angle-of-attack fairly high Best unlike flying-stab planes easy ginner tly recommend balance point CG placed right niiddle main spar also place tow hook right CG After try way can move CG and/or tow hook wherever yov can fly best good way -Add weight nose block balkust sheet lead can buy local plumbing shop cut shape tin snips used Ii-in wing wire primarily cause /4-in brass tubing required wAs same width spars easy align together desire can shim down wing wire size %s inserting A2-in GD /6-in ID tubing inside /4-in GD /32-in ID brass tubing will provide wing little give under sharp loads Sailplane design has its advantages disadvantageshigh lift high drag low drag low lift etc No design really perfect however feel Scooter good compromise Good lift Radio Technique/Myers Continued page 39 problems thanks Al Watson Gary Wild reports kind help makes job easier really enjoy hearing fr6m folks go out get valid test data selves instead wasting time listening Know-It-AIls havent actually done anything What else caii tell potential various kinds interference still present should monitor band order know what avoid its still good idea check DFC planning contest encounter problems new RC channels re port DFC Beyond can fly new RC channels con fidence Have acquired new hobby Im slow answering letters apologize know excuses Recently bought Kaypro II Word Processor attempt catch up letters pile Frequency Committee mail among other things Up till now Ive using WW II surplus Royal KMM typewriter needs new rubber nobody stocks parts Dick Jannson says should ashamed admit three kids college time what else would expect Anyhow see Bob Aberle spending 40 hours week Frequency Committee businessnow Im trying find way get job done smaller investment time Kayproll seems help picked Kaypro LI because meets needs complete cheapest complete package local support As Ive said before about hobby items believe important have local dealer support its possible save little money going through mail Youll have make up own mind about Im knocking mailorder houses Im dogmatic about either want something isnt carried locally like Circus Radios Kalt Helicopters dont have other choice except So call somebody toll-free line want parts just really didnt buy thing start other hobby seems have effect So readers have bright ideas about get best out tool about letting know about Kaypro II runs CP/M Version 22 Kaypro II trademark Kaypro Corp 533 Stevens Ave Solana Beach CA 92075 George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 Electrics/Kopski Continued page 42 same new As brushes wear frequently wear unevenly brush will wear much rapidly other ddnt know happens bUt does alwys put two new ones As new motor always break-in new brushes allowing motor run no prop very small prop cooling about 24 hours about halfthe normal voltage Instructions some elec tric motor systems discuss some come factory break-in break-in allows new brushes wear shape commutator seat better good 132 Model Aviation WAYNE ULERYS 1/3 SCALE LASER 200 THE PLANE THAT WON THE WEST span 9825 Wing area 1615 sq 18 lbs Eight LASERS flown 1982 T0C placed top twelve. Unique easy wing construction Foam cutting equipment required Special instructions pictures wing assembly Fiberglass cowl wheel pants plastic canopy 6061 T-6 aluminum wing spar 2024 T-4 landing gear available Information parts plans order SASE $2000 per set rolled plans Postage paid t5e Continental LISA Wayne Ulery 2564 Fox Hollow Rd Springfield Ohio 45502 both mechanical electrical reasons Commutators much harder mate rial brushes nomally wear away However brushes al lowed wear down completely metal brush arm brush springs begin ride commutator will wear tt will probably become scored motor performance will decline electrical noise due ex cessive sparking likely commutator could permanently ruined avoid problem best look brushes occasionally especially re placeable Some visible through bent holes disassembly necessary inspection Others easily removed exter nally brush holders unscrewing caps Handle brushes carefully cleanly replace same way came out Ive seen other problems brushcommutator area Some motors may begin display noticeable performance drop erratic running no apparent reason often associated excessive brush sparking possibly radio glitches may due inadequate brush pressure though brushes show little wear brush arms spring material lower-cost motors become overheated due motor being overworked some other reson may lose some tension Another effect high heat can com mutator distortion commutator gets out round brush bounce occurs case brushes excellent condition cant job fact Ive seen happen motors no way overworked commutator defective start can seen during break-in unloaded unpropped motor runs erratically can actually feel rotational irregulatiry hand commutator out round lay running motor table can watch twitch Use warranty card should motor defective received Both conditions inadequate brush pressure out-of-round com mutator can appreciated better apply ing some light pressure either brush through vent hole toothpick motor speed picks up smooths out no ticeably chances prob lems exists have relatively new cobalt motor has treated considerable care two occasions far performance suddenly dropped off Aerobatics model just wouldnt its usual tricks Close inspection revealed nothing unusual brushes commutator looked good battery pack etc normal brushes cobalt motor ride square brush guide tubes have coil springs brush pressure Upon re assembling brushes same brush same holder same orientation motor its old self again same thing happened visitor last years Electric Fly guess brushes become little snug guides pressure effectively reduced Perhaps some brush dust clogs guide bit Anyway removing brushes wiping tissue cleaning guide tube dry pipe cleaner does trick sure handle brushes carefully keep fingers off avoid possible con tamination Sometimes above conditions apply symptoms similar motor has run hard resulting high brush heat some brush material may smeared heavily commutator sur face prevent good electrical contact Try cure Take prop off run motor normal battery pack two three minutes Replace prop tached rpm before after may see noticeable improvement possible recommend making note motor/battery performance new after break-in generally note rpm particular prop size make battery voltage time Later theres question about performance data can compared unlike rangechecking radio rechecking under same conditions later date crash hard bump prop prop adaptor can easily bend armature shaft resulting obvious wobble vi bration Sometimes shaft can straight ened prop will run true armature may still wobble due shaft bend behind front bearing also causes brush bounce erratic running Like brushes some higher-quality motors have armature replacements can bought cases such above recourse unless youre ma chine work Sometimes impact can severe enough rear-end bell and/or bearing break get pushed out rearward-driven armature assembly Ive seen few crankshafts glow engines come through backplate too careful use flexible nylon prop and/or prop stop stop prop horizontal position minimize such problems E Bearings Electric motors models have either sleeve bearings ball bearings Usually sleeve bearings selflubricating self-centering motor 400 hts type new owner flew past 500 flights Finally bearing wear caused much noise embarrassed replaced motor about 12 dollars Thats about cost gallon you-know-what Ball bearings found larger and/or costly motors What kind un pleasant contradiction costly motor ball bearings non-replaceable brushes little like car nonreplaceable tires Given choice Im content sleeve bearings small motors Im convinced balls worth added cost kind flying may afford com petitive edge series flying addressed fun sport flying Whatever bearing type never add lu Con tinued page 136 THIS FUEL FEATURES RUST PREVENTION AGENTS ODETERGENTS OLUBRICATION WITH HIGH FLASH POINTS WETHNG AGENTS FOR MORE EFFICIENT AND DEPENDABLE FUEL FLOW OANTI-FOAMING AGENTS TO PREVENT LEAN RUNS KEEPS YOUR ENGINE RUNNING COOL OAN ODORLESS HIGHLY REFINED FUEL CHILDPROOF LIDS Available FAI 5 10 15 25 & 40% Nitro-Methane Contents Formulated synthetic lubricants Also available castor DEALERS WANTED DOMESTIC & OVERSEAS WE EXPORT competition tuel fast becoming THE CHOICE top protesonals ot tirst ro cash product Contact us price structures ordering information Manufacturers Major Brand Distilbutors Model Engines Kits Radios Accessones SUPER K Fuels brand KINGS RADIO CONTROL HOBBIES INTERNATIONAL 3960 West 16 Ave Hlaleah Florida 33012 305 557-2024 October 1983 133 1r specially formulated chemically balanced fuel top petformance minimum engine wear weather condition Electrics/Kopski Continued page 133 brication drop oil might find its way onto commutator surface brush material Thats end Im told F Other motor features Some other things make motor better use model aircraft often include wire set suitable polarized connector terminals easy connections Usually ca pacitors wired brush terminals help suppress electrical noise may otherwise interfere RC operation High-temperature insulation epoxy coat ing windings lacing wires commutator connections keep everything place good features too motors have finely finished bal anced armatures assure smooth vibrationfree operation Motors may have neutral tim ing turn equally well either direction others may have offset timing maximize performance normal di rection propeller use Some motors pack higher power han dling capability small case through use costly very high strength field mag nets such samarium cobalt material feature adds big bucks motor price armature shafts bend just easily sure pay particular attention land ing German Keller motor available flux rings metal bands slip over outside motor can make metal thicker Without case rela tively thin motor works best small props high revs case heavied-up rings motor develps higher torque turn larger props efficiently lower rpm Its like having variety motors 3 Motor size often subject much confusion beginners Its presently cause much ado modeling indus try Opinions vary to specify size classes Eventually some standards will emerge AMA SEAM Society Electric Aircraft Modelers other interested parties sort out best options necessarily simple task Un like gas engine typically char acterized its displacement cubic inches several candidate ways characterize classify electric motors way would measure physical size such armature perhaps overall motor weight Another way de scribe battery instead motor size class determined number and/or kind cells motor battery method used Europe FAt events will interesting see settled Eventually will important have some size designations allow orderly inevitable evolution competitive Elec tric events folks arent quite ready competition yet just trying get started series intended help As youll see some standards would very big help too First lets look what motor size has historically meant largest variety motors country have descriptions sound like gas engine sizes ex ample popular motor size 05 has come mean motor would swing same size prop about same rpm typical glow counterpart Thus 05 example would probably use 6-in diameter 4-in pitch prop would turn prop about same speed glow 049s Similarly electric IS might swine 8-4 prop sounds simple enough isnt Things changing Electric evolving some associated growing pains joys cobalt 05 example can easily out-power 049 glow engineand swing much heftier prop too Its really good ol 05 Other changes occurring too all-time favorites so-called 075 its old self anymore Despite same nomenclature catalog number windings now different long-developed familiarity goes out window least deserves new part number above given purpose confusing Rather illustrates creasine need size class standards reminds us present dynamics Builders Get f Better Start Season Using KIN-CRAFT Quality Line Polyester Resins Micro-Balloon Air-O-Fill Gloves Protective Fiberglass Cloth & Tapes 6 oz Cloth 1 4 & 6 Tapes Custom Cut Cloth Any Length Sandable Primers Thinner Accessories also Dust Masks Gator Grip Contact Cement Applicator Kits Engine Cleaner Oil Kits 2u Ii tj Ilobby Prod U IS Send self-addressed stamped envelope free catalogue discounts Dealer Distributor Inquiries Invited Kin-Craft Mig Ri 2 Box 481E Ashland KY 41101 606 928-4763 136 Model Aviation SUPERwings DIVISION oF HI JOHNSON MODEL PRODUCTS 11015 GLENOAKS BLVD PACOIMA CA 91331 SAILPLANE COMPONENTS CREATE YOUR OWN SUPER GLIDER WING FOAM CORES Floater Thermal & Slope FUSELAGES LUSTROLEEN 2 Meter Standard Open & Scale STAB FOAM CORES Rudder & Fin Cores COVERING MATERIALS White skin & Lustroleen WING RODS Wing Tongue Kits FOR HI JOHNSONS PORTFOLIO PRICE SHEET & ORDER FORM about sailplane construction & design using foam & plastic SEND $250 CHECK OR MO CA RES ADD SALES TAX AMA Clubs Giant Scalers Save 30%Order Direct Buckeye Balsa supplies AAA quality balsa certified aircraft plywood fine kits Aero Composites Double C Mfg Fliteglas Models Fourmost Products Kitty Hawk Models Dave Platt Precision Built Models R/C Kits Mfg VK ModIs Bob Dively Model Aircraft hobby shops Send $1 catalog Price applied first order Minimum Net Order $50 No sh pprng COD charges 216 533 3607 P0 Box 174 Canfield OH 44406 ALL SKEET ONE PIECE AAA GRADE KILN DRIED SANDED TO CLOSE TOLERANCES PED 100% Balsa Sheets36Light 46lb361/8 x 3453/16 sq 173/8 x 11/246 1/16 x 2331/16 x 3491/16 x 4481/4 sq 261/2 x 270 3/32 x 2403/32 x 3563/32x4561/4x3/8 30 1/8 x 2431/8 x 3671/8 x 4663/8 sq 37BalsaTriangles 3/16 x 2493/16 x 376 Sticks 6 1/4 x 2561/4 x 385 ched 40%1/4 x 1/425 3/8 x 3115 ets 423/8 x 3/830 1/16x3371/2 x 31393/32 x 4100 W1/2x1/235 3/32 x 3441/8 x 4108Basswood h Pine3/4x3/445 1/8 x 354BalsaSheets483/16x4120 cks For1 xl55 3/16 x 3621/16 x 3491/4 x 4131 Scale 1/4 x 3733/32 x 358Balsa Sticks36Lite Ply48 5/16x3851/8x3 711/8 x 6150 3/8 x 3883/16 x 3 821/16 x 1/409 1/2 x 31101/4x 33/32 x 1/410Birch Dowels 361/8 x 12300 3/4x31653/8x31241/Bsq.081/8 09 1/8x1/411 3/16113Ply Birch48 1/4141/64x12525 1 x3200 1/2x3155 1/8x1/2181/32x12425 1/16 X 4581/16 x 4763/16 sq.11Sendaddressed1/16 x 12435 3/32 x 4703/32 x 41/4 sq.16 1/8ic4801/8x41/4x1/221stanipedenvelope1/8x12450 3/16 x 4933/16 x 43/8sq.27 logue 1/4x4110 1/4x4134 318x1/232listingall sizesSPlyBirch48 3/32 x 12570 3/8x41653/8x4225 1/2sq.361/8x12585 1/2 x 4225Pine Sticks36 Trailing Edge 3/16 x 12585 NEWBalsa Sheets 30 1/8 sq.13361/4 x 12600 Quarter1/16 x 331 1/8 x 1/416 1/4*132 ScaleSizes3/32x337 1/8x3/820 5/16x11/439 accept Visa Master Card personal checks COD jiandling Charge $3 pay UPS Add $2 COD $3 extra PP SPO FPO 5% tax Texas US currency relatively new area model aviation So advised dont discouraged Some day future will good ol days' Electric new Standards lacking notwithstanding series will help get flying un derstand hows whys meantime consider lonely world df few US suppliers products electric-powered flight Im sure its long lean decade dedication per severance belief future thank stalwai-ts Im convinced major chunk modeldoms future de servedly Without wouldnt reading 4 When get good stuff nearing end Part Two series know readers may getting quite anxious get building flying something Thats quite under standable lets pause put whole Electric thing perspective Its rela tively new unfamiliar mLdelers including some very astute skilled Based inquiries receive subject continues bring far questions readily available answers Now consider popular continuing columns some modeling magazines devoted conventional engines Surely things have use bug enough everyone knows about right Nope Now consider basic arti cles have seen devoted electric motors electric flight batteries electric anything elseall unanswered questions right Look another way know someone flying group whos got together Hes guy experience engines always run just right maintains equipment specialist Helicopter Scale Rubber Com bat whatever guy knows awful lot about modeling general too knows what hes doing has good un derstanding basics uses full advantage series will have plenty to' examples go along its parallel goal convey basic understanding fundamental aspects electric-powered flight time-honored method teachingbasics plus examples Some text some lab work sorta under hat youll soon easily answering understanding such questions what motor needed fly what plane what should weigh assure much flight time Soon Electric products today will become dated will specific examples based dont want series become dated want continue basic value understanding utilization whatever new better prod ucts come along have reasod able acquaintance Elec tric works will have no trouble obtaining first-time continuing success Stay us youll person has together' Electric very anxious let suggest youre following series also keep eye contemporary magazines good source suitable Electric designs have already published MA alone has three four last year articles typically include electric system information design Later series will suggest guidelines motor plane combinations will assure success Also intallation coming As mentioned Part very versatile RC design Spectra can accommo Con tinued page 140 ATTENTION ERS October 1983 137 EPOXY GLASS COWLS FOR NOSEN PICA SIO MORGAN BALSA USA PLA TT CONCEPT FLEET HOSTETLER RCM T-CRAFT SHEBER P177S & SCALE SUPER CUB POKEER O7 BOEING P72 P26 F4B2 P464 SPARROW HA WE GEE BEE MOO r MACBRIEfSS TURBULEAIT CHRISTEN EAGLE BRISIGHELLAS STAROUSTEFf II A SCALE 1381 BABY FLYBABY AIRCAMPER PILOT JUNGMANN 735 SCALE 7/4 SCALE DECATIIALON PIPER PA- TB ft OThERS WHEEL PANTS FOR CITABRIA SrAROUS TER II PIUS SKYBOLT LIBERIYSPORT CHRISTEN EAGLE PBE HAWK STEARMAN STINSON SRB MULLIGAN & OTHERS BRAZED& HEAT-TREATED WIRE GEARS&CABANES LARGE SCALE PLANS AVAILABLE Send $100 latest list supply Modelers fiberglass parts plansWrite call us T & D FIBERGLASS SPECIALTIES 30925 eLOcK GARDEN CITY Mi 48135 PHONE 313 421-6358 r Finally.. 1/3 Scale Realism lightweight highly detailed realistic pilot figure scale R/C model aircraft figure Shown 1/3 scale civilian Seated approximately 125 tall 310 mm weighs 15 ounces comes complete including instructions painting fits 1/3 scale planes including Pitts Eagle Homebuilts ORDER YOURS TODAY Produced byPrice $1995 William M Hawke$200 shipping 7148 Lasting Light Way Columbia MD 21045 Ask dealer order diredt 1/4 scale coming soon L Electrics/Kopski Continued paqe 137 date variety electric power systems planned construction article Next up Part Three will discuss pro pellers electric power motors sole function convert energy stored battery propeller thrust Im sure will amazed just what takes turn prop various props com pare prop change affects flight performance think youll find Part Three enlightening though still fundamental also graphic unique dont think thing like has published before Part Four will devoted bat teries about batteries Installations planes follow Now answer title question good stuff will continue will eventually come together promise As continue challenge series Ive come appreciate its sizeable scope very difficult write compact complete simple Introduction Elec trics regard want thank wife Wilma MA Editor Carl Wheeley Columnist Bill Winter Electric flying friends KRCHerb Dirks John Hickey Heinz Koerner Don LeGower Dan Mittenfor critiquing drafts artworks helpful sugges tions Any questions related part earlier parts series may directed SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 RC Soaring/Pruss Continued page 45 helpful may have noticed skipped Fri days activity did because thats excitement occurred Fridays forecast thin layer four-day weather sandwich However based encouraging figures light winds aver age soaring conditions shutoff time day set 600 pm Published starting time four days 1000 am Troy Lawicki group Sil ver Eagles Soaring Society Michigan first course 1045 Several others followed logged very short flights Further attempts went way until about two oclock shortly after 17 Sailplanes air same time sight Nine working same thermal see 14-foot beau ties gracing same sky Contest Direc tor s reward time frame between 219 228 13 teams entered course included nine top 10 last years event test both Sailplane pilots skills purest form No gimmicks no trick launch equip ment no bad luck due bad draw can claimed protested against year con testants furnished own winches could launch exactly wanted Once air strategy overshadows luck ship capable bridging thermals moderate altitude trade off higher altitude because youll able cover ground once higher what about winds higher altitudes plowed fields plot ted course map just case need seek out hoping thermal being generated need day nature threw just crumb contestants way didnt last long Among gaggle 13 entered course about same time Jim Boh mer MOSS club group won event last year year retrieved model after 33 miles Skip Miller FAST first ever finish course official time managed 56-mile run relaunched logged 99 best effort during meet Six teams made about 20-mile mark Among Ken Bates Kurt Bak Mike McIntyre Ken Shaw MRCS Ann Abbor MI some six teams played lift hopes altitude before stretching down long southern course Bates left pack about half altitude highest plane group looked though wrong move After losing altitude down treetop height plowed field gave plane nudge upward Bates played thermal out new life made around south side course flew westward northbound forecast winds increased south provided team tailwind last half run Meanwhile south erly heading western leg coming down MRCS suddently course themselves Radio reports gave teams progress no question team con ditions favorable completing course question could beat clock well past three-hour mark air 600 pm shutoff nearing Passing last radio check point became very doubtful whether could finish course time rules state distance flown time shutdown will official distance time less seven minutes go still six miles flown radio reports made exciting Saturday sporting event drama moon launch countdown precisely 175930 official watches MRCS touched down com pleting 76 km1472 mile course three hours 32 minutes second time two years Bates company conquered Soarings greatest challenge also second time used makeshift bird year used wing very old Super Esprit parts other planes team Stan Watson Jim Slater Eric Stenson Dave Haertelrepresenting 4-STROKE ENGINE SALE COMPARE & SAVE Os FS 408950 OSFS6012500 OS FS 7514500 OS ES 120T34900 ENYA4O-4C12950 ENYA6O-4C14950 ENYA9O-4C18950 SAITO 308450 SAITO 40-Il9950 SAITO4510950 SAITO 90T29950 TERMS Prepaid check money order Include $250 UPS street address Calif residents add 6% sates tax No credit cards please Allow 2 weeks delivery REDWOOD hobby imports PO BOX 6171 SANTA ROSA CALIF 95401 Sublect stock hand 140 Model Aviation
Edition: Model Aviation - 1983/10
Page Numbers: 40, 41, 42, 132, 133, 136, 137, 140
Cutaway electric motor models Tom Chipley shows parts will help follow authors text heart system Electrics CAN SET SCREW ADAP FRONT BEARING about FIELD MAGNETS END BELLREAR BRUSHESBEARING 3 N\~ COMMUTATOR_ ARMATURE_CAPACITOR V. POLARIZED CONNECTOR w w w heart electric-powered airplane motor chapter describes whats motor provides some tips successful operation long useful life dont have know about elec tric motors enjoy flying Electrics youll ahead crowd Part 2 U Bob Kopski LAST MONTH highlighted features characteristics electric power noting advantages disadvantages showing varity electric-powered models broad range applicability con venience fun aspects relatively new form model power emphasized So much convincing Now does modeler average skill make hap pen Lets start getting know about electric motors sense knowledge about conventional gas power reciprocating enginesoften comes naturally feel comfortable familiar family car lawnmower engines Carburetor word unheard dinner table commutator thats bit unfamiliar unknown can bit scary purpose installment help feel comfortable electric motors describing some basics Ill get detail can use confidence Well cover some things should some things shouldnt may few things didnt know should Some things may seem necessary get started will surely help keep going Ill try make simple easy follow minimum heavy tech nical good dose plus plenty tidbits collected other single publication know Ill try arrange convenient sections can skip around interest need dictates easy future reference 1 Whats motor sections can skip over still start fly model other hand little bit information may help feel lot confident about subject because youll familiar what makes em hummmmmmm small direct current DC electric motors permanent magnet type used example batteryoperated toys applicances some auto accessories electric-powered air planes motors usually have two pieces strong magnetic material 40 Model Aviation motors typical readily available US modelers upper Astro 10 lower Leisure LT-50 Both have connecting wires convenient plugs well brush capacitors visible Leisure However have different kind prop adaptor i SQ Left Two kinds rear-end bells brushes connector cord has non-replaceable brushes well worn arms spring material Look closely may notice has no bearingthe result hard landing other rear-end assembly has replaceable brushes ball bearings armature shaft Coil springs provide bruah pressure left rear-end bell early Leisure motor other current Leisure LT-50 Center Two motor housings magnets intact left low-cost motor having front-end bell part drawn motor can Visible bearing two boles mounting screws two vent holes other housing has removable bells both ends Right Two typical armatures windings stripped oft clearly shows three poles poles made stacked thin iron laminations Drill marks top-most pole balancing final armature assembly Windings commutator visible left armature Left Hatch flipped back its tape hinge reveals rear cobalt 05 motor connector charging jack Look carefully might see brush dust inside fuselage hatch Note smooth nose block Persuader Acrobatic model Right Props 6 9-in diameter various prop adaptors held armature shafts setscrews pressed-on adaptors dont easily come off arent used much anymore Props may have drilled fit adaptors After boring balance achieve peak smoothness fixed opposite other inside round iron can housing field poles form strong magnetic field inside can armature assembly rotate within ends housing capped end bells ai least can usually removed Sometimes end simply part formed motor can end bells have centered bearings either bushing type ball type support armature shaft armature shaft holds stack thin iron laminations shaped form poles always odd number poles usually three seven Most small motors have three unmagnetized armature poles wound insulated copper wire. windings connected another part armature shaft called commutator commutator round insulator metal segments outer surface number segments equals number armature poles really rotary switch sequentially connects power source armature windings done through two spring-loaded sliding con tacts brushes ride ihe commutator segments armature assembly rotates two brushes normally mounted rear-end bell insulated other motor housing commutator segments bi-ushes carefully positioned relative armature poles housing field magnets respectively voltage applied external brush connections some ar mature polcs become electromagnetized just right place pushed others pulled field magnets forces cause armature begin rotating As commutator rotates new position power directed switched next winding set new poles will now pushed pulled stationary magnetic field timing characteristic similar auto engine sures proper sequential firing cylin ders As action continues motor armature spins seemingly smooth con tinuous rotationeven though electrical current being switched winding set next rapidly creating instant elec tromagnets out otherwise plain iron armature poles Start-up current can very heavy surge Once spinning however unloaded motor normally draws relatively little cur rent because sniall amounts electri cal power required overcome bear ing brush friction some other small power losses mechanical load applied motor shaft like propeller motor has work consequently electrical input power must increase Putting another way cant get something nothing Some examples illustrate will given later tn application motor acts convert extra electrical power input propeller thrust 2 Motors model use make motor suited model use some fea tures added basic machinery de scribed above Lets look impor tant ones some detail touch several others Prop adaptor fitting armature shaft extflding front motor either press-fitted held io shaft setscrew prefer shafts small flat setscrew get good bite onto prop adaptor may have threaded extension oh Which prop placed held washer nutvery similar gas engines prop adaptor may have inside thread prop held screw washer similar some small glow engines latter case multiple washers may supplied allow prop screw accept range prop hub thicknesses change screw length Its probably October 1983 41 5-40 thread almost impossible find anywhere B Motor mount Some method niounting motor needed Most motors have two four threaded holes frontend bell can used partially se cure motor Some motors have metal mounting clamps slip around housing form two beams similar glow engine Others have matching plastic mounts ease task installation personal preference structural motor mount 1 use part fuselage struc ture support motor often con junction aforementioned front-bell screw holes reducer mounting holes dont care slip motor tight tube type friction motor-holder popular early days Electrics Motor mounting sometimes stumbling block first-time Electric flier some proven methods will covered detail future meantime look accompanying photos get general idea C Venting thing am very big adequate venting motor During flight motor can develop significant internal heat fact properly used motor can get hot enough melt solder connections rapidly wear brushes As far Im concerned theres no such thing too much venting motor Most motors have openings front-end bell well rear vicinity brushes Vents must kept clear mounting motor provision must made motor air exit model struc ture Well see some ways future installment Ive learned hard way avoid motors no venting D Brushes etc very nice feature some motors replaceable brushes gen erally found costly and/or larger motors Brushes wear away fine dark colored brush dust exits hotor vents deposited some extent fuselage Dont worry powder harmful structure like oil Brush wear related hard work motor and/or effective venting Also brushes made differ ent materials affects wear rate lower-cost motors brush re placement possible brush wear may determining factor long motor lasts especially motor worked hard other hand once sold plane over 400 flights logged low-cost motor half original brush material remained time motor tached Continued page 132 42 Model Aviation four pictures show inside out kind structural motor mount motor mounted center pictures Astro 10 Dan Gravers sport flier named Friendly Two formers I/ Lite Ply provide support fore aft Cutout rear clearly offset right thrust obvious offset Dan has downthrust Nylon landing gear straps hold motor front former 6-32 screws front-end bell No 2 sheet-metal screws former Make cutouts round snug fit motor wrap plastic tape fixes minor misfits Two fuselage fronts having same kind structural motor mount motor slides rear through top hatch up against nylon right-angle brackets latter CyA glued 1/6. ply tube epoxied inside bored balsa block block turn glued fuselage sides carved smooth shape right fuselage has bottom skids prop-stop tubing 2 oclock spot variety motor mounts shown left plastic beam mount slips over motor housing setscrew holds tight Next structural motor mount natural part fuselage assembly third Mabuchi motor metal U-shaped clamps meet form mounting beams clamps also serve flux rings note air vents arent covered right another plastic mount radial type also held setscrew attaches cutout firewall four screws Thrust adlustments direction easy radial mount Phase Art Best Custom Screen Sportswear \~kl 4893SNu Piper Cub NATS Shirts Still Available See Bealeton VASept 17 8 18 Greenville SCSept 23 Stratford CTOct 1 FAI Championships Pensacola FLOct 10-14 Designs just come aviation designs available top quality line sportswear designs direct printno heat transfer Three color B-25. Piper Cub. Bee. P40 Warha wks kker D VII. P-3. AT-6. Christen Eagle. Pitts Special. Citabria. P47 Thunderbolt earman Curtis enny. Corsair. coaches shirtS1295TShirt$695 LadiCs TopSSSOLong Sleeve T$795 Shorts$5SSBesebell$S95 Lined JacketS2195Football$S95 Tote Bag$9SSweetshirt$950 Tire coverS1495Hooded Sweot$1495 HatS595 Wide choice colors aizesi Send $100 new illustrated Brochure Refundable First Order Name Address cityStateZip DesignSize Color now accept MasterCard & Visa TO ORDER Send check money order Shipping $1-is add 5150 Over $15 add 10% Maryland residents add 5% taxI Phase Art 17102 Earlham Ct Upper Marlboro MD 20772 1301 8433050 wings find have root rib WI little crooked have tapered fairing blocks properly now good timc fit wid root fuselage hLindy sanding block Covering may use whatever covering material desirc though highly recom mend MonoKote combination like cover bottom surfaces dark easy-to-see color cover top lighter brighter color pleases eSe Radio installation fuselage little smallonly wide servo area room two medium-size servos like Kraft KPS-14 though like small Futaba S-2t mounting two S-20s forward possible leaves little access space allows mounting switch Bulkhead F2 Snap-Lip pushrods install receiver bet dre install switch switch button sticking ward through F can lift canopy easily operate use larger servos will have mount switch dit receiver between Bulkheads F3 F4 battery compartment will take Kraft KB-4M 450 Futaba NR-4G 225 pack Flying Scooter very stable glides fairly fgst turns tightly minimum loss altitude stalling angle-of-attack fairly high Best unlike flying-stab planes easy ginner tly recommend balance point CG placed right niiddle main spar also place tow hook right CG After try way can move CG and/or tow hook wherever yov can fly best good way -Add weight nose block balkust sheet lead can buy local plumbing shop cut shape tin snips used Ii-in wing wire primarily cause /4-in brass tubing required wAs same width spars easy align together desire can shim down wing wire size %s inserting A2-in GD /6-in ID tubing inside /4-in GD /32-in ID brass tubing will provide wing little give under sharp loads Sailplane design has its advantages disadvantageshigh lift high drag low drag low lift etc No design really perfect however feel Scooter good compromise Good lift Radio Technique/Myers Continued page 39 problems thanks Al Watson Gary Wild reports kind help makes job easier really enjoy hearing fr6m folks go out get valid test data selves instead wasting time listening Know-It-AIls havent actually done anything What else caii tell potential various kinds interference still present should monitor band order know what avoid its still good idea check DFC planning contest encounter problems new RC channels re port DFC Beyond can fly new RC channels con fidence Have acquired new hobby Im slow answering letters apologize know excuses Recently bought Kaypro II Word Processor attempt catch up letters pile Frequency Committee mail among other things Up till now Ive using WW II surplus Royal KMM typewriter needs new rubber nobody stocks parts Dick Jannson says should ashamed admit three kids college time what else would expect Anyhow see Bob Aberle spending 40 hours week Frequency Committee businessnow Im trying find way get job done smaller investment time Kayproll seems help picked Kaypro LI because meets needs complete cheapest complete package local support As Ive said before about hobby items believe important have local dealer support its possible save little money going through mail Youll have make up own mind about Im knocking mailorder houses Im dogmatic about either want something isnt carried locally like Circus Radios Kalt Helicopters dont have other choice except So call somebody toll-free line want parts just really didnt buy thing start other hobby seems have effect So readers have bright ideas about get best out tool about letting know about Kaypro II runs CP/M Version 22 Kaypro II trademark Kaypro Corp 533 Stevens Ave Solana Beach CA 92075 George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 Electrics/Kopski Continued page 42 same new As brushes wear frequently wear unevenly brush will wear much rapidly other ddnt know happens bUt does alwys put two new ones As new motor always break-in new brushes allowing motor run no prop very small prop cooling about 24 hours about halfthe normal voltage Instructions some elec tric motor systems discuss some come factory break-in break-in allows new brushes wear shape commutator seat better good 132 Model Aviation WAYNE ULERYS 1/3 SCALE LASER 200 THE PLANE THAT WON THE WEST span 9825 Wing area 1615 sq 18 lbs Eight LASERS flown 1982 T0C placed top twelve. Unique easy wing construction Foam cutting equipment required Special instructions pictures wing assembly Fiberglass cowl wheel pants plastic canopy 6061 T-6 aluminum wing spar 2024 T-4 landing gear available Information parts plans order SASE $2000 per set rolled plans Postage paid t5e Continental LISA Wayne Ulery 2564 Fox Hollow Rd Springfield Ohio 45502 both mechanical electrical reasons Commutators much harder mate rial brushes nomally wear away However brushes al lowed wear down completely metal brush arm brush springs begin ride commutator will wear tt will probably become scored motor performance will decline electrical noise due ex cessive sparking likely commutator could permanently ruined avoid problem best look brushes occasionally especially re placeable Some visible through bent holes disassembly necessary inspection Others easily removed exter nally brush holders unscrewing caps Handle brushes carefully cleanly replace same way came out Ive seen other problems brushcommutator area Some motors may begin display noticeable performance drop erratic running no apparent reason often associated excessive brush sparking possibly radio glitches may due inadequate brush pressure though brushes show little wear brush arms spring material lower-cost motors become overheated due motor being overworked some other reson may lose some tension Another effect high heat can com mutator distortion commutator gets out round brush bounce occurs case brushes excellent condition cant job fact Ive seen happen motors no way overworked commutator defective start can seen during break-in unloaded unpropped motor runs erratically can actually feel rotational irregulatiry hand commutator out round lay running motor table can watch twitch Use warranty card should motor defective received Both conditions inadequate brush pressure out-of-round com mutator can appreciated better apply ing some light pressure either brush through vent hole toothpick motor speed picks up smooths out no ticeably chances prob lems exists have relatively new cobalt motor has treated considerable care two occasions far performance suddenly dropped off Aerobatics model just wouldnt its usual tricks Close inspection revealed nothing unusual brushes commutator looked good battery pack etc normal brushes cobalt motor ride square brush guide tubes have coil springs brush pressure Upon re assembling brushes same brush same holder same orientation motor its old self again same thing happened visitor last years Electric Fly guess brushes become little snug guides pressure effectively reduced Perhaps some brush dust clogs guide bit Anyway removing brushes wiping tissue cleaning guide tube dry pipe cleaner does trick sure handle brushes carefully keep fingers off avoid possible con tamination Sometimes above conditions apply symptoms similar motor has run hard resulting high brush heat some brush material may smeared heavily commutator sur face prevent good electrical contact Try cure Take prop off run motor normal battery pack two three minutes Replace prop tached rpm before after may see noticeable improvement possible recommend making note motor/battery performance new after break-in generally note rpm particular prop size make battery voltage time Later theres question about performance data can compared unlike rangechecking radio rechecking under same conditions later date crash hard bump prop prop adaptor can easily bend armature shaft resulting obvious wobble vi bration Sometimes shaft can straight ened prop will run true armature may still wobble due shaft bend behind front bearing also causes brush bounce erratic running Like brushes some higher-quality motors have armature replacements can bought cases such above recourse unless youre ma chine work Sometimes impact can severe enough rear-end bell and/or bearing break get pushed out rearward-driven armature assembly Ive seen few crankshafts glow engines come through backplate too careful use flexible nylon prop and/or prop stop stop prop horizontal position minimize such problems E Bearings Electric motors models have either sleeve bearings ball bearings Usually sleeve bearings selflubricating self-centering motor 400 hts type new owner flew past 500 flights Finally bearing wear caused much noise embarrassed replaced motor about 12 dollars Thats about cost gallon you-know-what Ball bearings found larger and/or costly motors What kind un pleasant contradiction costly motor ball bearings non-replaceable brushes little like car nonreplaceable tires Given choice Im content sleeve bearings small motors Im convinced balls worth added cost kind flying may afford com petitive edge series flying addressed fun sport flying Whatever bearing type never add lu Con tinued page 136 THIS FUEL FEATURES RUST PREVENTION AGENTS ODETERGENTS OLUBRICATION WITH HIGH FLASH POINTS WETHNG AGENTS FOR MORE EFFICIENT AND DEPENDABLE FUEL FLOW OANTI-FOAMING AGENTS TO PREVENT LEAN RUNS KEEPS YOUR ENGINE RUNNING COOL OAN ODORLESS HIGHLY REFINED FUEL CHILDPROOF LIDS Available FAI 5 10 15 25 & 40% Nitro-Methane Contents Formulated synthetic lubricants Also available castor DEALERS WANTED DOMESTIC & OVERSEAS WE EXPORT competition tuel fast becoming THE CHOICE top protesonals ot tirst ro cash product Contact us price structures ordering information Manufacturers Major Brand Distilbutors Model Engines Kits Radios Accessones SUPER K Fuels brand KINGS RADIO CONTROL HOBBIES INTERNATIONAL 3960 West 16 Ave Hlaleah Florida 33012 305 557-2024 October 1983 133 1r specially formulated chemically balanced fuel top petformance minimum engine wear weather condition Electrics/Kopski Continued page 133 brication drop oil might find its way onto commutator surface brush material Thats end Im told F Other motor features Some other things make motor better use model aircraft often include wire set suitable polarized connector terminals easy connections Usually ca pacitors wired brush terminals help suppress electrical noise may otherwise interfere RC operation High-temperature insulation epoxy coat ing windings lacing wires commutator connections keep everything place good features too motors have finely finished bal anced armatures assure smooth vibrationfree operation Motors may have neutral tim ing turn equally well either direction others may have offset timing maximize performance normal di rection propeller use Some motors pack higher power han dling capability small case through use costly very high strength field mag nets such samarium cobalt material feature adds big bucks motor price armature shafts bend just easily sure pay particular attention land ing German Keller motor available flux rings metal bands slip over outside motor can make metal thicker Without case rela tively thin motor works best small props high revs case heavied-up rings motor develps higher torque turn larger props efficiently lower rpm Its like having variety motors 3 Motor size often subject much confusion beginners Its presently cause much ado modeling indus try Opinions vary to specify size classes Eventually some standards will emerge AMA SEAM Society Electric Aircraft Modelers other interested parties sort out best options necessarily simple task Un like gas engine typically char acterized its displacement cubic inches several candidate ways characterize classify electric motors way would measure physical size such armature perhaps overall motor weight Another way de scribe battery instead motor size class determined number and/or kind cells motor battery method used Europe FAt events will interesting see settled Eventually will important have some size designations allow orderly inevitable evolution competitive Elec tric events folks arent quite ready competition yet just trying get started series intended help As youll see some standards would very big help too First lets look what motor size has historically meant largest variety motors country have descriptions sound like gas engine sizes ex ample popular motor size 05 has come mean motor would swing same size prop about same rpm typical glow counterpart Thus 05 example would probably use 6-in diameter 4-in pitch prop would turn prop about same speed glow 049s Similarly electric IS might swine 8-4 prop sounds simple enough isnt Things changing Electric evolving some associated growing pains joys cobalt 05 example can easily out-power 049 glow engineand swing much heftier prop too Its really good ol 05 Other changes occurring too all-time favorites so-called 075 its old self anymore Despite same nomenclature catalog number windings now different long-developed familiarity goes out window least deserves new part number above given purpose confusing Rather illustrates creasine need size class standards reminds us present dynamics Builders Get f Better Start Season Using KIN-CRAFT Quality Line Polyester Resins Micro-Balloon Air-O-Fill Gloves Protective Fiberglass Cloth & Tapes 6 oz Cloth 1 4 & 6 Tapes Custom Cut Cloth Any Length Sandable Primers Thinner Accessories also Dust Masks Gator Grip Contact Cement Applicator Kits Engine Cleaner Oil Kits 2u Ii tj Ilobby Prod U IS Send self-addressed stamped envelope free catalogue discounts Dealer Distributor Inquiries Invited Kin-Craft Mig Ri 2 Box 481E Ashland KY 41101 606 928-4763 136 Model Aviation SUPERwings DIVISION oF HI JOHNSON MODEL PRODUCTS 11015 GLENOAKS BLVD PACOIMA CA 91331 SAILPLANE COMPONENTS CREATE YOUR OWN SUPER GLIDER WING FOAM CORES Floater Thermal & Slope FUSELAGES LUSTROLEEN 2 Meter Standard Open & Scale STAB FOAM CORES Rudder & Fin Cores COVERING MATERIALS White skin & Lustroleen WING RODS Wing Tongue Kits FOR HI JOHNSONS PORTFOLIO PRICE SHEET & ORDER FORM about sailplane construction & design using foam & plastic SEND $250 CHECK OR MO CA RES ADD SALES TAX AMA Clubs Giant Scalers Save 30%Order Direct Buckeye Balsa supplies AAA quality balsa certified aircraft plywood fine kits Aero Composites Double C Mfg Fliteglas Models Fourmost Products Kitty Hawk Models Dave Platt Precision Built Models R/C Kits Mfg VK ModIs Bob Dively Model Aircraft hobby shops Send $1 catalog Price applied first order Minimum Net Order $50 No sh pprng COD charges 216 533 3607 P0 Box 174 Canfield OH 44406 ALL SKEET ONE PIECE AAA GRADE KILN DRIED SANDED TO CLOSE TOLERANCES PED 100% Balsa Sheets36Light 46lb361/8 x 3453/16 sq 173/8 x 11/246 1/16 x 2331/16 x 3491/16 x 4481/4 sq 261/2 x 270 3/32 x 2403/32 x 3563/32x4561/4x3/8 30 1/8 x 2431/8 x 3671/8 x 4663/8 sq 37BalsaTriangles 3/16 x 2493/16 x 376 Sticks 6 1/4 x 2561/4 x 385 ched 40%1/4 x 1/425 3/8 x 3115 ets 423/8 x 3/830 1/16x3371/2 x 31393/32 x 4100 W1/2x1/235 3/32 x 3441/8 x 4108Basswood h Pine3/4x3/445 1/8 x 354BalsaSheets483/16x4120 cks For1 xl55 3/16 x 3621/16 x 3491/4 x 4131 Scale 1/4 x 3733/32 x 358Balsa Sticks36Lite Ply48 5/16x3851/8x3 711/8 x 6150 3/8 x 3883/16 x 3 821/16 x 1/409 1/2 x 31101/4x 33/32 x 1/410Birch Dowels 361/8 x 12300 3/4x31653/8x31241/Bsq.081/8 09 1/8x1/411 3/16113Ply Birch48 1/4141/64x12525 1 x3200 1/2x3155 1/8x1/2181/32x12425 1/16 X 4581/16 x 4763/16 sq.11Sendaddressed1/16 x 12435 3/32 x 4703/32 x 41/4 sq.16 1/8ic4801/8x41/4x1/221stanipedenvelope1/8x12450 3/16 x 4933/16 x 43/8sq.27 logue 1/4x4110 1/4x4134 318x1/232listingall sizesSPlyBirch48 3/32 x 12570 3/8x41653/8x4225 1/2sq.361/8x12585 1/2 x 4225Pine Sticks36 Trailing Edge 3/16 x 12585 NEWBalsa Sheets 30 1/8 sq.13361/4 x 12600 Quarter1/16 x 331 1/8 x 1/416 1/4*132 ScaleSizes3/32x337 1/8x3/820 5/16x11/439 accept Visa Master Card personal checks COD jiandling Charge $3 pay UPS Add $2 COD $3 extra PP SPO FPO 5% tax Texas US currency relatively new area model aviation So advised dont discouraged Some day future will good ol days' Electric new Standards lacking notwithstanding series will help get flying un derstand hows whys meantime consider lonely world df few US suppliers products electric-powered flight Im sure its long lean decade dedication per severance belief future thank stalwai-ts Im convinced major chunk modeldoms future de servedly Without wouldnt reading 4 When get good stuff nearing end Part Two series know readers may getting quite anxious get building flying something Thats quite under standable lets pause put whole Electric thing perspective Its rela tively new unfamiliar mLdelers including some very astute skilled Based inquiries receive subject continues bring far questions readily available answers Now consider popular continuing columns some modeling magazines devoted conventional engines Surely things have use bug enough everyone knows about right Nope Now consider basic arti cles have seen devoted electric motors electric flight batteries electric anything elseall unanswered questions right Look another way know someone flying group whos got together Hes guy experience engines always run just right maintains equipment specialist Helicopter Scale Rubber Com bat whatever guy knows awful lot about modeling general too knows what hes doing has good un derstanding basics uses full advantage series will have plenty to' examples go along its parallel goal convey basic understanding fundamental aspects electric-powered flight time-honored method teachingbasics plus examples Some text some lab work sorta under hat youll soon easily answering understanding such questions what motor needed fly what plane what should weigh assure much flight time Soon Electric products today will become dated will specific examples based dont want series become dated want continue basic value understanding utilization whatever new better prod ucts come along have reasod able acquaintance Elec tric works will have no trouble obtaining first-time continuing success Stay us youll person has together' Electric very anxious let suggest youre following series also keep eye contemporary magazines good source suitable Electric designs have already published MA alone has three four last year articles typically include electric system information design Later series will suggest guidelines motor plane combinations will assure success Also intallation coming As mentioned Part very versatile RC design Spectra can accommo Con tinued page 140 ATTENTION ERS October 1983 137 EPOXY GLASS COWLS FOR NOSEN PICA SIO MORGAN BALSA USA PLA TT CONCEPT FLEET HOSTETLER RCM T-CRAFT SHEBER P177S & SCALE SUPER CUB POKEER O7 BOEING P72 P26 F4B2 P464 SPARROW HA WE GEE BEE MOO r MACBRIEfSS TURBULEAIT CHRISTEN EAGLE BRISIGHELLAS STAROUSTEFf II A SCALE 1381 BABY FLYBABY AIRCAMPER PILOT JUNGMANN 735 SCALE 7/4 SCALE DECATIIALON PIPER PA- TB ft OThERS WHEEL PANTS FOR CITABRIA SrAROUS TER II PIUS SKYBOLT LIBERIYSPORT CHRISTEN EAGLE PBE HAWK STEARMAN STINSON SRB MULLIGAN & OTHERS BRAZED& HEAT-TREATED WIRE GEARS&CABANES LARGE SCALE PLANS AVAILABLE Send $100 latest list supply Modelers fiberglass parts plansWrite call us T & D FIBERGLASS SPECIALTIES 30925 eLOcK GARDEN CITY Mi 48135 PHONE 313 421-6358 r Finally.. 1/3 Scale Realism lightweight highly detailed realistic pilot figure scale R/C model aircraft figure Shown 1/3 scale civilian Seated approximately 125 tall 310 mm weighs 15 ounces comes complete including instructions painting fits 1/3 scale planes including Pitts Eagle Homebuilts ORDER YOURS TODAY Produced byPrice $1995 William M Hawke$200 shipping 7148 Lasting Light Way Columbia MD 21045 Ask dealer order diredt 1/4 scale coming soon L Electrics/Kopski Continued paqe 137 date variety electric power systems planned construction article Next up Part Three will discuss pro pellers electric power motors sole function convert energy stored battery propeller thrust Im sure will amazed just what takes turn prop various props com pare prop change affects flight performance think youll find Part Three enlightening though still fundamental also graphic unique dont think thing like has published before Part Four will devoted bat teries about batteries Installations planes follow Now answer title question good stuff will continue will eventually come together promise As continue challenge series Ive come appreciate its sizeable scope very difficult write compact complete simple Introduction Elec trics regard want thank wife Wilma MA Editor Carl Wheeley Columnist Bill Winter Electric flying friends KRCHerb Dirks John Hickey Heinz Koerner Don LeGower Dan Mittenfor critiquing drafts artworks helpful sugges tions Any questions related part earlier parts series may directed SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 RC Soaring/Pruss Continued page 45 helpful may have noticed skipped Fri days activity did because thats excitement occurred Fridays forecast thin layer four-day weather sandwich However based encouraging figures light winds aver age soaring conditions shutoff time day set 600 pm Published starting time four days 1000 am Troy Lawicki group Sil ver Eagles Soaring Society Michigan first course 1045 Several others followed logged very short flights Further attempts went way until about two oclock shortly after 17 Sailplanes air same time sight Nine working same thermal see 14-foot beau ties gracing same sky Contest Direc tor s reward time frame between 219 228 13 teams entered course included nine top 10 last years event test both Sailplane pilots skills purest form No gimmicks no trick launch equip ment no bad luck due bad draw can claimed protested against year con testants furnished own winches could launch exactly wanted Once air strategy overshadows luck ship capable bridging thermals moderate altitude trade off higher altitude because youll able cover ground once higher what about winds higher altitudes plowed fields plot ted course map just case need seek out hoping thermal being generated need day nature threw just crumb contestants way didnt last long Among gaggle 13 entered course about same time Jim Boh mer MOSS club group won event last year year retrieved model after 33 miles Skip Miller FAST first ever finish course official time managed 56-mile run relaunched logged 99 best effort during meet Six teams made about 20-mile mark Among Ken Bates Kurt Bak Mike McIntyre Ken Shaw MRCS Ann Abbor MI some six teams played lift hopes altitude before stretching down long southern course Bates left pack about half altitude highest plane group looked though wrong move After losing altitude down treetop height plowed field gave plane nudge upward Bates played thermal out new life made around south side course flew westward northbound forecast winds increased south provided team tailwind last half run Meanwhile south erly heading western leg coming down MRCS suddently course themselves Radio reports gave teams progress no question team con ditions favorable completing course question could beat clock well past three-hour mark air 600 pm shutoff nearing Passing last radio check point became very doubtful whether could finish course time rules state distance flown time shutdown will official distance time less seven minutes go still six miles flown radio reports made exciting Saturday sporting event drama moon launch countdown precisely 175930 official watches MRCS touched down com pleting 76 km1472 mile course three hours 32 minutes second time two years Bates company conquered Soarings greatest challenge also second time used makeshift bird year used wing very old Super Esprit parts other planes team Stan Watson Jim Slater Eric Stenson Dave Haertelrepresenting 4-STROKE ENGINE SALE COMPARE & SAVE Os FS 408950 OSFS6012500 OS FS 7514500 OS ES 120T34900 ENYA4O-4C12950 ENYA6O-4C14950 ENYA9O-4C18950 SAITO 308450 SAITO 40-Il9950 SAITO4510950 SAITO 90T29950 TERMS Prepaid check money order Include $250 UPS street address Calif residents add 6% sates tax No credit cards please Allow 2 weeks delivery REDWOOD hobby imports PO BOX 6171 SANTA ROSA CALIF 95401 Sublect stock hand 140 Model Aviation
Edition: Model Aviation - 1983/10
Page Numbers: 40, 41, 42, 132, 133, 136, 137, 140
Cutaway electric motor models Tom Chipley shows parts will help follow authors text heart system Electrics CAN SET SCREW ADAP FRONT BEARING about FIELD MAGNETS END BELLREAR BRUSHESBEARING 3 N\~ COMMUTATOR_ ARMATURE_CAPACITOR V. POLARIZED CONNECTOR w w w heart electric-powered airplane motor chapter describes whats motor provides some tips successful operation long useful life dont have know about elec tric motors enjoy flying Electrics youll ahead crowd Part 2 U Bob Kopski LAST MONTH highlighted features characteristics electric power noting advantages disadvantages showing varity electric-powered models broad range applicability con venience fun aspects relatively new form model power emphasized So much convincing Now does modeler average skill make hap pen Lets start getting know about electric motors sense knowledge about conventional gas power reciprocating enginesoften comes naturally feel comfortable familiar family car lawnmower engines Carburetor word unheard dinner table commutator thats bit unfamiliar unknown can bit scary purpose installment help feel comfortable electric motors describing some basics Ill get detail can use confidence Well cover some things should some things shouldnt may few things didnt know should Some things may seem necessary get started will surely help keep going Ill try make simple easy follow minimum heavy tech nical good dose plus plenty tidbits collected other single publication know Ill try arrange convenient sections can skip around interest need dictates easy future reference 1 Whats motor sections can skip over still start fly model other hand little bit information may help feel lot confident about subject because youll familiar what makes em hummmmmmm small direct current DC electric motors permanent magnet type used example batteryoperated toys applicances some auto accessories electric-powered air planes motors usually have two pieces strong magnetic material 40 Model Aviation motors typical readily available US modelers upper Astro 10 lower Leisure LT-50 Both have connecting wires convenient plugs well brush capacitors visible Leisure However have different kind prop adaptor i SQ Left Two kinds rear-end bells brushes connector cord has non-replaceable brushes well worn arms spring material Look closely may notice has no bearingthe result hard landing other rear-end assembly has replaceable brushes ball bearings armature shaft Coil springs provide bruah pressure left rear-end bell early Leisure motor other current Leisure LT-50 Center Two motor housings magnets intact left low-cost motor having front-end bell part drawn motor can Visible bearing two boles mounting screws two vent holes other housing has removable bells both ends Right Two typical armatures windings stripped oft clearly shows three poles poles made stacked thin iron laminations Drill marks top-most pole balancing final armature assembly Windings commutator visible left armature Left Hatch flipped back its tape hinge reveals rear cobalt 05 motor connector charging jack Look carefully might see brush dust inside fuselage hatch Note smooth nose block Persuader Acrobatic model Right Props 6 9-in diameter various prop adaptors held armature shafts setscrews pressed-on adaptors dont easily come off arent used much anymore Props may have drilled fit adaptors After boring balance achieve peak smoothness fixed opposite other inside round iron can housing field poles form strong magnetic field inside can armature assembly rotate within ends housing capped end bells ai least can usually removed Sometimes end simply part formed motor can end bells have centered bearings either bushing type ball type support armature shaft armature shaft holds stack thin iron laminations shaped form poles always odd number poles usually three seven Most small motors have three unmagnetized armature poles wound insulated copper wire. windings connected another part armature shaft called commutator commutator round insulator metal segments outer surface number segments equals number armature poles really rotary switch sequentially connects power source armature windings done through two spring-loaded sliding con tacts brushes ride ihe commutator segments armature assembly rotates two brushes normally mounted rear-end bell insulated other motor housing commutator segments bi-ushes carefully positioned relative armature poles housing field magnets respectively voltage applied external brush connections some ar mature polcs become electromagnetized just right place pushed others pulled field magnets forces cause armature begin rotating As commutator rotates new position power directed switched next winding set new poles will now pushed pulled stationary magnetic field timing characteristic similar auto engine sures proper sequential firing cylin ders As action continues motor armature spins seemingly smooth con tinuous rotationeven though electrical current being switched winding set next rapidly creating instant elec tromagnets out otherwise plain iron armature poles Start-up current can very heavy surge Once spinning however unloaded motor normally draws relatively little cur rent because sniall amounts electri cal power required overcome bear ing brush friction some other small power losses mechanical load applied motor shaft like propeller motor has work consequently electrical input power must increase Putting another way cant get something nothing Some examples illustrate will given later tn application motor acts convert extra electrical power input propeller thrust 2 Motors model use make motor suited model use some fea tures added basic machinery de scribed above Lets look impor tant ones some detail touch several others Prop adaptor fitting armature shaft extflding front motor either press-fitted held io shaft setscrew prefer shafts small flat setscrew get good bite onto prop adaptor may have threaded extension oh Which prop placed held washer nutvery similar gas engines prop adaptor may have inside thread prop held screw washer similar some small glow engines latter case multiple washers may supplied allow prop screw accept range prop hub thicknesses change screw length Its probably October 1983 41 5-40 thread almost impossible find anywhere B Motor mount Some method niounting motor needed Most motors have two four threaded holes frontend bell can used partially se cure motor Some motors have metal mounting clamps slip around housing form two beams similar glow engine Others have matching plastic mounts ease task installation personal preference structural motor mount 1 use part fuselage struc ture support motor often con junction aforementioned front-bell screw holes reducer mounting holes dont care slip motor tight tube type friction motor-holder popular early days Electrics Motor mounting sometimes stumbling block first-time Electric flier some proven methods will covered detail future meantime look accompanying photos get general idea C Venting thing am very big adequate venting motor During flight motor can develop significant internal heat fact properly used motor can get hot enough melt solder connections rapidly wear brushes As far Im concerned theres no such thing too much venting motor Most motors have openings front-end bell well rear vicinity brushes Vents must kept clear mounting motor provision must made motor air exit model struc ture Well see some ways future installment Ive learned hard way avoid motors no venting D Brushes etc very nice feature some motors replaceable brushes gen erally found costly and/or larger motors Brushes wear away fine dark colored brush dust exits hotor vents deposited some extent fuselage Dont worry powder harmful structure like oil Brush wear related hard work motor and/or effective venting Also brushes made differ ent materials affects wear rate lower-cost motors brush re placement possible brush wear may determining factor long motor lasts especially motor worked hard other hand once sold plane over 400 flights logged low-cost motor half original brush material remained time motor tached Continued page 132 42 Model Aviation four pictures show inside out kind structural motor mount motor mounted center pictures Astro 10 Dan Gravers sport flier named Friendly Two formers I/ Lite Ply provide support fore aft Cutout rear clearly offset right thrust obvious offset Dan has downthrust Nylon landing gear straps hold motor front former 6-32 screws front-end bell No 2 sheet-metal screws former Make cutouts round snug fit motor wrap plastic tape fixes minor misfits Two fuselage fronts having same kind structural motor mount motor slides rear through top hatch up against nylon right-angle brackets latter CyA glued 1/6. ply tube epoxied inside bored balsa block block turn glued fuselage sides carved smooth shape right fuselage has bottom skids prop-stop tubing 2 oclock spot variety motor mounts shown left plastic beam mount slips over motor housing setscrew holds tight Next structural motor mount natural part fuselage assembly third Mabuchi motor metal U-shaped clamps meet form mounting beams clamps also serve flux rings note air vents arent covered right another plastic mount radial type also held setscrew attaches cutout firewall four screws Thrust adlustments direction easy radial mount Phase Art Best Custom Screen Sportswear \~kl 4893SNu Piper Cub NATS Shirts Still Available See Bealeton VASept 17 8 18 Greenville SCSept 23 Stratford CTOct 1 FAI Championships Pensacola FLOct 10-14 Designs just come aviation designs available top quality line sportswear designs direct printno heat transfer Three color B-25. Piper Cub. Bee. P40 Warha wks kker D VII. P-3. AT-6. Christen Eagle. Pitts Special. Citabria. P47 Thunderbolt earman Curtis enny. Corsair. coaches shirtS1295TShirt$695 LadiCs TopSSSOLong Sleeve T$795 Shorts$5SSBesebell$S95 Lined JacketS2195Football$S95 Tote Bag$9SSweetshirt$950 Tire coverS1495Hooded Sweot$1495 HatS595 Wide choice colors aizesi Send $100 new illustrated Brochure Refundable First Order Name Address cityStateZip DesignSize Color now accept MasterCard & Visa TO ORDER Send check money order Shipping $1-is add 5150 Over $15 add 10% Maryland residents add 5% taxI Phase Art 17102 Earlham Ct Upper Marlboro MD 20772 1301 8433050 wings find have root rib WI little crooked have tapered fairing blocks properly now good timc fit wid root fuselage hLindy sanding block Covering may use whatever covering material desirc though highly recom mend MonoKote combination like cover bottom surfaces dark easy-to-see color cover top lighter brighter color pleases eSe Radio installation fuselage little smallonly wide servo area room two medium-size servos like Kraft KPS-14 though like small Futaba S-2t mounting two S-20s forward possible leaves little access space allows mounting switch Bulkhead F2 Snap-Lip pushrods install receiver bet dre install switch switch button sticking ward through F can lift canopy easily operate use larger servos will have mount switch dit receiver between Bulkheads F3 F4 battery compartment will take Kraft KB-4M 450 Futaba NR-4G 225 pack Flying Scooter very stable glides fairly fgst turns tightly minimum loss altitude stalling angle-of-attack fairly high Best unlike flying-stab planes easy ginner tly recommend balance point CG placed right niiddle main spar also place tow hook right CG After try way can move CG and/or tow hook wherever yov can fly best good way -Add weight nose block balkust sheet lead can buy local plumbing shop cut shape tin snips used Ii-in wing wire primarily cause /4-in brass tubing required wAs same width spars easy align together desire can shim down wing wire size %s inserting A2-in GD /6-in ID tubing inside /4-in GD /32-in ID brass tubing will provide wing little give under sharp loads Sailplane design has its advantages disadvantageshigh lift high drag low drag low lift etc No design really perfect however feel Scooter good compromise Good lift Radio Technique/Myers Continued page 39 problems thanks Al Watson Gary Wild reports kind help makes job easier really enjoy hearing fr6m folks go out get valid test data selves instead wasting time listening Know-It-AIls havent actually done anything What else caii tell potential various kinds interference still present should monitor band order know what avoid its still good idea check DFC planning contest encounter problems new RC channels re port DFC Beyond can fly new RC channels con fidence Have acquired new hobby Im slow answering letters apologize know excuses Recently bought Kaypro II Word Processor attempt catch up letters pile Frequency Committee mail among other things Up till now Ive using WW II surplus Royal KMM typewriter needs new rubber nobody stocks parts Dick Jannson says should ashamed admit three kids college time what else would expect Anyhow see Bob Aberle spending 40 hours week Frequency Committee businessnow Im trying find way get job done smaller investment time Kayproll seems help picked Kaypro LI because meets needs complete cheapest complete package local support As Ive said before about hobby items believe important have local dealer support its possible save little money going through mail Youll have make up own mind about Im knocking mailorder houses Im dogmatic about either want something isnt carried locally like Circus Radios Kalt Helicopters dont have other choice except So call somebody toll-free line want parts just really didnt buy thing start other hobby seems have effect So readers have bright ideas about get best out tool about letting know about Kaypro II runs CP/M Version 22 Kaypro II trademark Kaypro Corp 533 Stevens Ave Solana Beach CA 92075 George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 Electrics/Kopski Continued page 42 same new As brushes wear frequently wear unevenly brush will wear much rapidly other ddnt know happens bUt does alwys put two new ones As new motor always break-in new brushes allowing motor run no prop very small prop cooling about 24 hours about halfthe normal voltage Instructions some elec tric motor systems discuss some come factory break-in break-in allows new brushes wear shape commutator seat better good 132 Model Aviation WAYNE ULERYS 1/3 SCALE LASER 200 THE PLANE THAT WON THE WEST span 9825 Wing area 1615 sq 18 lbs Eight LASERS flown 1982 T0C placed top twelve. Unique easy wing construction Foam cutting equipment required Special instructions pictures wing assembly Fiberglass cowl wheel pants plastic canopy 6061 T-6 aluminum wing spar 2024 T-4 landing gear available Information parts plans order SASE $2000 per set rolled plans Postage paid t5e Continental LISA Wayne Ulery 2564 Fox Hollow Rd Springfield Ohio 45502 both mechanical electrical reasons Commutators much harder mate rial brushes nomally wear away However brushes al lowed wear down completely metal brush arm brush springs begin ride commutator will wear tt will probably become scored motor performance will decline electrical noise due ex cessive sparking likely commutator could permanently ruined avoid problem best look brushes occasionally especially re placeable Some visible through bent holes disassembly necessary inspection Others easily removed exter nally brush holders unscrewing caps Handle brushes carefully cleanly replace same way came out Ive seen other problems brushcommutator area Some motors may begin display noticeable performance drop erratic running no apparent reason often associated excessive brush sparking possibly radio glitches may due inadequate brush pressure though brushes show little wear brush arms spring material lower-cost motors become overheated due motor being overworked some other reson may lose some tension Another effect high heat can com mutator distortion commutator gets out round brush bounce occurs case brushes excellent condition cant job fact Ive seen happen motors no way overworked commutator defective start can seen during break-in unloaded unpropped motor runs erratically can actually feel rotational irregulatiry hand commutator out round lay running motor table can watch twitch Use warranty card should motor defective received Both conditions inadequate brush pressure out-of-round com mutator can appreciated better apply ing some light pressure either brush through vent hole toothpick motor speed picks up smooths out no ticeably chances prob lems exists have relatively new cobalt motor has treated considerable care two occasions far performance suddenly dropped off Aerobatics model just wouldnt its usual tricks Close inspection revealed nothing unusual brushes commutator looked good battery pack etc normal brushes cobalt motor ride square brush guide tubes have coil springs brush pressure Upon re assembling brushes same brush same holder same orientation motor its old self again same thing happened visitor last years Electric Fly guess brushes become little snug guides pressure effectively reduced Perhaps some brush dust clogs guide bit Anyway removing brushes wiping tissue cleaning guide tube dry pipe cleaner does trick sure handle brushes carefully keep fingers off avoid possible con tamination Sometimes above conditions apply symptoms similar motor has run hard resulting high brush heat some brush material may smeared heavily commutator sur face prevent good electrical contact Try cure Take prop off run motor normal battery pack two three minutes Replace prop tached rpm before after may see noticeable improvement possible recommend making note motor/battery performance new after break-in generally note rpm particular prop size make battery voltage time Later theres question about performance data can compared unlike rangechecking radio rechecking under same conditions later date crash hard bump prop prop adaptor can easily bend armature shaft resulting obvious wobble vi bration Sometimes shaft can straight ened prop will run true armature may still wobble due shaft bend behind front bearing also causes brush bounce erratic running Like brushes some higher-quality motors have armature replacements can bought cases such above recourse unless youre ma chine work Sometimes impact can severe enough rear-end bell and/or bearing break get pushed out rearward-driven armature assembly Ive seen few crankshafts glow engines come through backplate too careful use flexible nylon prop and/or prop stop stop prop horizontal position minimize such problems E Bearings Electric motors models have either sleeve bearings ball bearings Usually sleeve bearings selflubricating self-centering motor 400 hts type new owner flew past 500 flights Finally bearing wear caused much noise embarrassed replaced motor about 12 dollars Thats about cost gallon you-know-what Ball bearings found larger and/or costly motors What kind un pleasant contradiction costly motor ball bearings non-replaceable brushes little like car nonreplaceable tires Given choice Im content sleeve bearings small motors Im convinced balls worth added cost kind flying may afford com petitive edge series flying addressed fun sport flying Whatever bearing type never add lu Con tinued page 136 THIS FUEL FEATURES RUST PREVENTION AGENTS ODETERGENTS OLUBRICATION WITH HIGH FLASH POINTS WETHNG AGENTS FOR MORE EFFICIENT AND DEPENDABLE FUEL FLOW OANTI-FOAMING AGENTS TO PREVENT LEAN RUNS KEEPS YOUR ENGINE RUNNING COOL OAN ODORLESS HIGHLY REFINED FUEL CHILDPROOF LIDS Available FAI 5 10 15 25 & 40% Nitro-Methane Contents Formulated synthetic lubricants Also available castor DEALERS WANTED DOMESTIC & OVERSEAS WE EXPORT competition tuel fast becoming THE CHOICE top protesonals ot tirst ro cash product Contact us price structures ordering information Manufacturers Major Brand Distilbutors Model Engines Kits Radios Accessones SUPER K Fuels brand KINGS RADIO CONTROL HOBBIES INTERNATIONAL 3960 West 16 Ave Hlaleah Florida 33012 305 557-2024 October 1983 133 1r specially formulated chemically balanced fuel top petformance minimum engine wear weather condition Electrics/Kopski Continued page 133 brication drop oil might find its way onto commutator surface brush material Thats end Im told F Other motor features Some other things make motor better use model aircraft often include wire set suitable polarized connector terminals easy connections Usually ca pacitors wired brush terminals help suppress electrical noise may otherwise interfere RC operation High-temperature insulation epoxy coat ing windings lacing wires commutator connections keep everything place good features too motors have finely finished bal anced armatures assure smooth vibrationfree operation Motors may have neutral tim ing turn equally well either direction others may have offset timing maximize performance normal di rection propeller use Some motors pack higher power han dling capability small case through use costly very high strength field mag nets such samarium cobalt material feature adds big bucks motor price armature shafts bend just easily sure pay particular attention land ing German Keller motor available flux rings metal bands slip over outside motor can make metal thicker Without case rela tively thin motor works best small props high revs case heavied-up rings motor develps higher torque turn larger props efficiently lower rpm Its like having variety motors 3 Motor size often subject much confusion beginners Its presently cause much ado modeling indus try Opinions vary to specify size classes Eventually some standards will emerge AMA SEAM Society Electric Aircraft Modelers other interested parties sort out best options necessarily simple task Un like gas engine typically char acterized its displacement cubic inches several candidate ways characterize classify electric motors way would measure physical size such armature perhaps overall motor weight Another way de scribe battery instead motor size class determined number and/or kind cells motor battery method used Europe FAt events will interesting see settled Eventually will important have some size designations allow orderly inevitable evolution competitive Elec tric events folks arent quite ready competition yet just trying get started series intended help As youll see some standards would very big help too First lets look what motor size has historically meant largest variety motors country have descriptions sound like gas engine sizes ex ample popular motor size 05 has come mean motor would swing same size prop about same rpm typical glow counterpart Thus 05 example would probably use 6-in diameter 4-in pitch prop would turn prop about same speed glow 049s Similarly electric IS might swine 8-4 prop sounds simple enough isnt Things changing Electric evolving some associated growing pains joys cobalt 05 example can easily out-power 049 glow engineand swing much heftier prop too Its really good ol 05 Other changes occurring too all-time favorites so-called 075 its old self anymore Despite same nomenclature catalog number windings now different long-developed familiarity goes out window least deserves new part number above given purpose confusing Rather illustrates creasine need size class standards reminds us present dynamics Builders Get f Better Start Season Using KIN-CRAFT Quality Line Polyester Resins Micro-Balloon Air-O-Fill Gloves Protective Fiberglass Cloth & Tapes 6 oz Cloth 1 4 & 6 Tapes Custom Cut Cloth Any Length Sandable Primers Thinner Accessories also Dust Masks Gator Grip Contact Cement Applicator Kits Engine Cleaner Oil Kits 2u Ii tj Ilobby Prod U IS Send self-addressed stamped envelope free catalogue discounts Dealer Distributor Inquiries Invited Kin-Craft Mig Ri 2 Box 481E Ashland KY 41101 606 928-4763 136 Model Aviation SUPERwings DIVISION oF HI JOHNSON MODEL PRODUCTS 11015 GLENOAKS BLVD PACOIMA CA 91331 SAILPLANE COMPONENTS CREATE YOUR OWN SUPER GLIDER WING FOAM CORES Floater Thermal & Slope FUSELAGES LUSTROLEEN 2 Meter Standard Open & Scale STAB FOAM CORES Rudder & Fin Cores COVERING MATERIALS White skin & Lustroleen WING RODS Wing Tongue Kits FOR HI JOHNSONS PORTFOLIO PRICE SHEET & ORDER FORM about sailplane construction & design using foam & plastic SEND $250 CHECK OR MO CA RES ADD SALES TAX AMA Clubs Giant Scalers Save 30%Order Direct Buckeye Balsa supplies AAA quality balsa certified aircraft plywood fine kits Aero Composites Double C Mfg Fliteglas Models Fourmost Products Kitty Hawk Models Dave Platt Precision Built Models R/C Kits Mfg VK ModIs Bob Dively Model Aircraft hobby shops Send $1 catalog Price applied first order Minimum Net Order $50 No sh pprng COD charges 216 533 3607 P0 Box 174 Canfield OH 44406 ALL SKEET ONE PIECE AAA GRADE KILN DRIED SANDED TO CLOSE TOLERANCES PED 100% Balsa Sheets36Light 46lb361/8 x 3453/16 sq 173/8 x 11/246 1/16 x 2331/16 x 3491/16 x 4481/4 sq 261/2 x 270 3/32 x 2403/32 x 3563/32x4561/4x3/8 30 1/8 x 2431/8 x 3671/8 x 4663/8 sq 37BalsaTriangles 3/16 x 2493/16 x 376 Sticks 6 1/4 x 2561/4 x 385 ched 40%1/4 x 1/425 3/8 x 3115 ets 423/8 x 3/830 1/16x3371/2 x 31393/32 x 4100 W1/2x1/235 3/32 x 3441/8 x 4108Basswood h Pine3/4x3/445 1/8 x 354BalsaSheets483/16x4120 cks For1 xl55 3/16 x 3621/16 x 3491/4 x 4131 Scale 1/4 x 3733/32 x 358Balsa Sticks36Lite Ply48 5/16x3851/8x3 711/8 x 6150 3/8 x 3883/16 x 3 821/16 x 1/409 1/2 x 31101/4x 33/32 x 1/410Birch Dowels 361/8 x 12300 3/4x31653/8x31241/Bsq.081/8 09 1/8x1/411 3/16113Ply Birch48 1/4141/64x12525 1 x3200 1/2x3155 1/8x1/2181/32x12425 1/16 X 4581/16 x 4763/16 sq.11Sendaddressed1/16 x 12435 3/32 x 4703/32 x 41/4 sq.16 1/8ic4801/8x41/4x1/221stanipedenvelope1/8x12450 3/16 x 4933/16 x 43/8sq.27 logue 1/4x4110 1/4x4134 318x1/232listingall sizesSPlyBirch48 3/32 x 12570 3/8x41653/8x4225 1/2sq.361/8x12585 1/2 x 4225Pine Sticks36 Trailing Edge 3/16 x 12585 NEWBalsa Sheets 30 1/8 sq.13361/4 x 12600 Quarter1/16 x 331 1/8 x 1/416 1/4*132 ScaleSizes3/32x337 1/8x3/820 5/16x11/439 accept Visa Master Card personal checks COD jiandling Charge $3 pay UPS Add $2 COD $3 extra PP SPO FPO 5% tax Texas US currency relatively new area model aviation So advised dont discouraged Some day future will good ol days' Electric new Standards lacking notwithstanding series will help get flying un derstand hows whys meantime consider lonely world df few US suppliers products electric-powered flight Im sure its long lean decade dedication per severance belief future thank stalwai-ts Im convinced major chunk modeldoms future de servedly Without wouldnt reading 4 When get good stuff nearing end Part Two series know readers may getting quite anxious get building flying something Thats quite under standable lets pause put whole Electric thing perspective Its rela tively new unfamiliar mLdelers including some very astute skilled Based inquiries receive subject continues bring far questions readily available answers Now consider popular continuing columns some modeling magazines devoted conventional engines Surely things have use bug enough everyone knows about right Nope Now consider basic arti cles have seen devoted electric motors electric flight batteries electric anything elseall unanswered questions right Look another way know someone flying group whos got together Hes guy experience engines always run just right maintains equipment specialist Helicopter Scale Rubber Com bat whatever guy knows awful lot about modeling general too knows what hes doing has good un derstanding basics uses full advantage series will have plenty to' examples go along its parallel goal convey basic understanding fundamental aspects electric-powered flight time-honored method teachingbasics plus examples Some text some lab work sorta under hat youll soon easily answering understanding such questions what motor needed fly what plane what should weigh assure much flight time Soon Electric products today will become dated will specific examples based dont want series become dated want continue basic value understanding utilization whatever new better prod ucts come along have reasod able acquaintance Elec tric works will have no trouble obtaining first-time continuing success Stay us youll person has together' Electric very anxious let suggest youre following series also keep eye contemporary magazines good source suitable Electric designs have already published MA alone has three four last year articles typically include electric system information design Later series will suggest guidelines motor plane combinations will assure success Also intallation coming As mentioned Part very versatile RC design Spectra can accommo Con tinued page 140 ATTENTION ERS October 1983 137 EPOXY GLASS COWLS FOR NOSEN PICA SIO MORGAN BALSA USA PLA TT CONCEPT FLEET HOSTETLER RCM T-CRAFT SHEBER P177S & SCALE SUPER CUB POKEER O7 BOEING P72 P26 F4B2 P464 SPARROW HA WE GEE BEE MOO r MACBRIEfSS TURBULEAIT CHRISTEN EAGLE BRISIGHELLAS STAROUSTEFf II A SCALE 1381 BABY FLYBABY AIRCAMPER PILOT JUNGMANN 735 SCALE 7/4 SCALE DECATIIALON PIPER PA- TB ft OThERS WHEEL PANTS FOR CITABRIA SrAROUS TER II PIUS SKYBOLT LIBERIYSPORT CHRISTEN EAGLE PBE HAWK STEARMAN STINSON SRB MULLIGAN & OTHERS BRAZED& HEAT-TREATED WIRE GEARS&CABANES LARGE SCALE PLANS AVAILABLE Send $100 latest list supply Modelers fiberglass parts plansWrite call us T & D FIBERGLASS SPECIALTIES 30925 eLOcK GARDEN CITY Mi 48135 PHONE 313 421-6358 r Finally.. 1/3 Scale Realism lightweight highly detailed realistic pilot figure scale R/C model aircraft figure Shown 1/3 scale civilian Seated approximately 125 tall 310 mm weighs 15 ounces comes complete including instructions painting fits 1/3 scale planes including Pitts Eagle Homebuilts ORDER YOURS TODAY Produced byPrice $1995 William M Hawke$200 shipping 7148 Lasting Light Way Columbia MD 21045 Ask dealer order diredt 1/4 scale coming soon L Electrics/Kopski Continued paqe 137 date variety electric power systems planned construction article Next up Part Three will discuss pro pellers electric power motors sole function convert energy stored battery propeller thrust Im sure will amazed just what takes turn prop various props com pare prop change affects flight performance think youll find Part Three enlightening though still fundamental also graphic unique dont think thing like has published before Part Four will devoted bat teries about batteries Installations planes follow Now answer title question good stuff will continue will eventually come together promise As continue challenge series Ive come appreciate its sizeable scope very difficult write compact complete simple Introduction Elec trics regard want thank wife Wilma MA Editor Carl Wheeley Columnist Bill Winter Electric flying friends KRCHerb Dirks John Hickey Heinz Koerner Don LeGower Dan Mittenfor critiquing drafts artworks helpful sugges tions Any questions related part earlier parts series may directed SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 RC Soaring/Pruss Continued page 45 helpful may have noticed skipped Fri days activity did because thats excitement occurred Fridays forecast thin layer four-day weather sandwich However based encouraging figures light winds aver age soaring conditions shutoff time day set 600 pm Published starting time four days 1000 am Troy Lawicki group Sil ver Eagles Soaring Society Michigan first course 1045 Several others followed logged very short flights Further attempts went way until about two oclock shortly after 17 Sailplanes air same time sight Nine working same thermal see 14-foot beau ties gracing same sky Contest Direc tor s reward time frame between 219 228 13 teams entered course included nine top 10 last years event test both Sailplane pilots skills purest form No gimmicks no trick launch equip ment no bad luck due bad draw can claimed protested against year con testants furnished own winches could launch exactly wanted Once air strategy overshadows luck ship capable bridging thermals moderate altitude trade off higher altitude because youll able cover ground once higher what about winds higher altitudes plowed fields plot ted course map just case need seek out hoping thermal being generated need day nature threw just crumb contestants way didnt last long Among gaggle 13 entered course about same time Jim Boh mer MOSS club group won event last year year retrieved model after 33 miles Skip Miller FAST first ever finish course official time managed 56-mile run relaunched logged 99 best effort during meet Six teams made about 20-mile mark Among Ken Bates Kurt Bak Mike McIntyre Ken Shaw MRCS Ann Abbor MI some six teams played lift hopes altitude before stretching down long southern course Bates left pack about half altitude highest plane group looked though wrong move After losing altitude down treetop height plowed field gave plane nudge upward Bates played thermal out new life made around south side course flew westward northbound forecast winds increased south provided team tailwind last half run Meanwhile south erly heading western leg coming down MRCS suddently course themselves Radio reports gave teams progress no question team con ditions favorable completing course question could beat clock well past three-hour mark air 600 pm shutoff nearing Passing last radio check point became very doubtful whether could finish course time rules state distance flown time shutdown will official distance time less seven minutes go still six miles flown radio reports made exciting Saturday sporting event drama moon launch countdown precisely 175930 official watches MRCS touched down com pleting 76 km1472 mile course three hours 32 minutes second time two years Bates company conquered Soarings greatest challenge also second time used makeshift bird year used wing very old Super Esprit parts other planes team Stan Watson Jim Slater Eric Stenson Dave Haertelrepresenting 4-STROKE ENGINE SALE COMPARE & SAVE Os FS 408950 OSFS6012500 OS FS 7514500 OS ES 120T34900 ENYA4O-4C12950 ENYA6O-4C14950 ENYA9O-4C18950 SAITO 308450 SAITO 40-Il9950 SAITO4510950 SAITO 90T29950 TERMS Prepaid check money order Include $250 UPS street address Calif residents add 6% sates tax No credit cards please Allow 2 weeks delivery REDWOOD hobby imports PO BOX 6171 SANTA ROSA CALIF 95401 Sublect stock hand 140 Model Aviation
Edition: Model Aviation - 1983/10
Page Numbers: 40, 41, 42, 132, 133, 136, 137, 140
Cutaway electric motor models Tom Chipley shows parts will help follow authors text heart system Electrics CAN SET SCREW ADAP FRONT BEARING about FIELD MAGNETS END BELLREAR BRUSHESBEARING 3 N\~ COMMUTATOR_ ARMATURE_CAPACITOR V. POLARIZED CONNECTOR w w w heart electric-powered airplane motor chapter describes whats motor provides some tips successful operation long useful life dont have know about elec tric motors enjoy flying Electrics youll ahead crowd Part 2 U Bob Kopski LAST MONTH highlighted features characteristics electric power noting advantages disadvantages showing varity electric-powered models broad range applicability con venience fun aspects relatively new form model power emphasized So much convincing Now does modeler average skill make hap pen Lets start getting know about electric motors sense knowledge about conventional gas power reciprocating enginesoften comes naturally feel comfortable familiar family car lawnmower engines Carburetor word unheard dinner table commutator thats bit unfamiliar unknown can bit scary purpose installment help feel comfortable electric motors describing some basics Ill get detail can use confidence Well cover some things should some things shouldnt may few things didnt know should Some things may seem necessary get started will surely help keep going Ill try make simple easy follow minimum heavy tech nical good dose plus plenty tidbits collected other single publication know Ill try arrange convenient sections can skip around interest need dictates easy future reference 1 Whats motor sections can skip over still start fly model other hand little bit information may help feel lot confident about subject because youll familiar what makes em hummmmmmm small direct current DC electric motors permanent magnet type used example batteryoperated toys applicances some auto accessories electric-powered air planes motors usually have two pieces strong magnetic material 40 Model Aviation motors typical readily available US modelers upper Astro 10 lower Leisure LT-50 Both have connecting wires convenient plugs well brush capacitors visible Leisure However have different kind prop adaptor i SQ Left Two kinds rear-end bells brushes connector cord has non-replaceable brushes well worn arms spring material Look closely may notice has no bearingthe result hard landing other rear-end assembly has replaceable brushes ball bearings armature shaft Coil springs provide bruah pressure left rear-end bell early Leisure motor other current Leisure LT-50 Center Two motor housings magnets intact left low-cost motor having front-end bell part drawn motor can Visible bearing two boles mounting screws two vent holes other housing has removable bells both ends Right Two typical armatures windings stripped oft clearly shows three poles poles made stacked thin iron laminations Drill marks top-most pole balancing final armature assembly Windings commutator visible left armature Left Hatch flipped back its tape hinge reveals rear cobalt 05 motor connector charging jack Look carefully might see brush dust inside fuselage hatch Note smooth nose block Persuader Acrobatic model Right Props 6 9-in diameter various prop adaptors held armature shafts setscrews pressed-on adaptors dont easily come off arent used much anymore Props may have drilled fit adaptors After boring balance achieve peak smoothness fixed opposite other inside round iron can housing field poles form strong magnetic field inside can armature assembly rotate within ends housing capped end bells ai least can usually removed Sometimes end simply part formed motor can end bells have centered bearings either bushing type ball type support armature shaft armature shaft holds stack thin iron laminations shaped form poles always odd number poles usually three seven Most small motors have three unmagnetized armature poles wound insulated copper wire. windings connected another part armature shaft called commutator commutator round insulator metal segments outer surface number segments equals number armature poles really rotary switch sequentially connects power source armature windings done through two spring-loaded sliding con tacts brushes ride ihe commutator segments armature assembly rotates two brushes normally mounted rear-end bell insulated other motor housing commutator segments bi-ushes carefully positioned relative armature poles housing field magnets respectively voltage applied external brush connections some ar mature polcs become electromagnetized just right place pushed others pulled field magnets forces cause armature begin rotating As commutator rotates new position power directed switched next winding set new poles will now pushed pulled stationary magnetic field timing characteristic similar auto engine sures proper sequential firing cylin ders As action continues motor armature spins seemingly smooth con tinuous rotationeven though electrical current being switched winding set next rapidly creating instant elec tromagnets out otherwise plain iron armature poles Start-up current can very heavy surge Once spinning however unloaded motor normally draws relatively little cur rent because sniall amounts electri cal power required overcome bear ing brush friction some other small power losses mechanical load applied motor shaft like propeller motor has work consequently electrical input power must increase Putting another way cant get something nothing Some examples illustrate will given later tn application motor acts convert extra electrical power input propeller thrust 2 Motors model use make motor suited model use some fea tures added basic machinery de scribed above Lets look impor tant ones some detail touch several others Prop adaptor fitting armature shaft extflding front motor either press-fitted held io shaft setscrew prefer shafts small flat setscrew get good bite onto prop adaptor may have threaded extension oh Which prop placed held washer nutvery similar gas engines prop adaptor may have inside thread prop held screw washer similar some small glow engines latter case multiple washers may supplied allow prop screw accept range prop hub thicknesses change screw length Its probably October 1983 41 5-40 thread almost impossible find anywhere B Motor mount Some method niounting motor needed Most motors have two four threaded holes frontend bell can used partially se cure motor Some motors have metal mounting clamps slip around housing form two beams similar glow engine Others have matching plastic mounts ease task installation personal preference structural motor mount 1 use part fuselage struc ture support motor often con junction aforementioned front-bell screw holes reducer mounting holes dont care slip motor tight tube type friction motor-holder popular early days Electrics Motor mounting sometimes stumbling block first-time Electric flier some proven methods will covered detail future meantime look accompanying photos get general idea C Venting thing am very big adequate venting motor During flight motor can develop significant internal heat fact properly used motor can get hot enough melt solder connections rapidly wear brushes As far Im concerned theres no such thing too much venting motor Most motors have openings front-end bell well rear vicinity brushes Vents must kept clear mounting motor provision must made motor air exit model struc ture Well see some ways future installment Ive learned hard way avoid motors no venting D Brushes etc very nice feature some motors replaceable brushes gen erally found costly and/or larger motors Brushes wear away fine dark colored brush dust exits hotor vents deposited some extent fuselage Dont worry powder harmful structure like oil Brush wear related hard work motor and/or effective venting Also brushes made differ ent materials affects wear rate lower-cost motors brush re placement possible brush wear may determining factor long motor lasts especially motor worked hard other hand once sold plane over 400 flights logged low-cost motor half original brush material remained time motor tached Continued page 132 42 Model Aviation four pictures show inside out kind structural motor mount motor mounted center pictures Astro 10 Dan Gravers sport flier named Friendly Two formers I/ Lite Ply provide support fore aft Cutout rear clearly offset right thrust obvious offset Dan has downthrust Nylon landing gear straps hold motor front former 6-32 screws front-end bell No 2 sheet-metal screws former Make cutouts round snug fit motor wrap plastic tape fixes minor misfits Two fuselage fronts having same kind structural motor mount motor slides rear through top hatch up against nylon right-angle brackets latter CyA glued 1/6. ply tube epoxied inside bored balsa block block turn glued fuselage sides carved smooth shape right fuselage has bottom skids prop-stop tubing 2 oclock spot variety motor mounts shown left plastic beam mount slips over motor housing setscrew holds tight Next structural motor mount natural part fuselage assembly third Mabuchi motor metal U-shaped clamps meet form mounting beams clamps also serve flux rings note air vents arent covered right another plastic mount radial type also held setscrew attaches cutout firewall four screws Thrust adlustments direction easy radial mount Phase Art Best Custom Screen Sportswear \~kl 4893SNu Piper Cub NATS Shirts Still Available See Bealeton VASept 17 8 18 Greenville SCSept 23 Stratford CTOct 1 FAI Championships Pensacola FLOct 10-14 Designs just come aviation designs available top quality line sportswear designs direct printno heat transfer Three color B-25. Piper Cub. Bee. P40 Warha wks kker D VII. P-3. AT-6. Christen Eagle. Pitts Special. Citabria. P47 Thunderbolt earman Curtis enny. Corsair. coaches shirtS1295TShirt$695 LadiCs TopSSSOLong Sleeve T$795 Shorts$5SSBesebell$S95 Lined JacketS2195Football$S95 Tote Bag$9SSweetshirt$950 Tire coverS1495Hooded Sweot$1495 HatS595 Wide choice colors aizesi Send $100 new illustrated Brochure Refundable First Order Name Address cityStateZip DesignSize Color now accept MasterCard & Visa TO ORDER Send check money order Shipping $1-is add 5150 Over $15 add 10% Maryland residents add 5% taxI Phase Art 17102 Earlham Ct Upper Marlboro MD 20772 1301 8433050 wings find have root rib WI little crooked have tapered fairing blocks properly now good timc fit wid root fuselage hLindy sanding block Covering may use whatever covering material desirc though highly recom mend MonoKote combination like cover bottom surfaces dark easy-to-see color cover top lighter brighter color pleases eSe Radio installation fuselage little smallonly wide servo area room two medium-size servos like Kraft KPS-14 though like small Futaba S-2t mounting two S-20s forward possible leaves little access space allows mounting switch Bulkhead F2 Snap-Lip pushrods install receiver bet dre install switch switch button sticking ward through F can lift canopy easily operate use larger servos will have mount switch dit receiver between Bulkheads F3 F4 battery compartment will take Kraft KB-4M 450 Futaba NR-4G 225 pack Flying Scooter very stable glides fairly fgst turns tightly minimum loss altitude stalling angle-of-attack fairly high Best unlike flying-stab planes easy ginner tly recommend balance point CG placed right niiddle main spar also place tow hook right CG After try way can move CG and/or tow hook wherever yov can fly best good way -Add weight nose block balkust sheet lead can buy local plumbing shop cut shape tin snips used Ii-in wing wire primarily cause /4-in brass tubing required wAs same width spars easy align together desire can shim down wing wire size %s inserting A2-in GD /6-in ID tubing inside /4-in GD /32-in ID brass tubing will provide wing little give under sharp loads Sailplane design has its advantages disadvantageshigh lift high drag low drag low lift etc No design really perfect however feel Scooter good compromise Good lift Radio Technique/Myers Continued page 39 problems thanks Al Watson Gary Wild reports kind help makes job easier really enjoy hearing fr6m folks go out get valid test data selves instead wasting time listening Know-It-AIls havent actually done anything What else caii tell potential various kinds interference still present should monitor band order know what avoid its still good idea check DFC planning contest encounter problems new RC channels re port DFC Beyond can fly new RC channels con fidence Have acquired new hobby Im slow answering letters apologize know excuses Recently bought Kaypro II Word Processor attempt catch up letters pile Frequency Committee mail among other things Up till now Ive using WW II surplus Royal KMM typewriter needs new rubber nobody stocks parts Dick Jannson says should ashamed admit three kids college time what else would expect Anyhow see Bob Aberle spending 40 hours week Frequency Committee businessnow Im trying find way get job done smaller investment time Kayproll seems help picked Kaypro LI because meets needs complete cheapest complete package local support As Ive said before about hobby items believe important have local dealer support its possible save little money going through mail Youll have make up own mind about Im knocking mailorder houses Im dogmatic about either want something isnt carried locally like Circus Radios Kalt Helicopters dont have other choice except So call somebody toll-free line want parts just really didnt buy thing start other hobby seems have effect So readers have bright ideas about get best out tool about letting know about Kaypro II runs CP/M Version 22 Kaypro II trademark Kaypro Corp 533 Stevens Ave Solana Beach CA 92075 George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 Electrics/Kopski Continued page 42 same new As brushes wear frequently wear unevenly brush will wear much rapidly other ddnt know happens bUt does alwys put two new ones As new motor always break-in new brushes allowing motor run no prop very small prop cooling about 24 hours about halfthe normal voltage Instructions some elec tric motor systems discuss some come factory break-in break-in allows new brushes wear shape commutator seat better good 132 Model Aviation WAYNE ULERYS 1/3 SCALE LASER 200 THE PLANE THAT WON THE WEST span 9825 Wing area 1615 sq 18 lbs Eight LASERS flown 1982 T0C placed top twelve. Unique easy wing construction Foam cutting equipment required Special instructions pictures wing assembly Fiberglass cowl wheel pants plastic canopy 6061 T-6 aluminum wing spar 2024 T-4 landing gear available Information parts plans order SASE $2000 per set rolled plans Postage paid t5e Continental LISA Wayne Ulery 2564 Fox Hollow Rd Springfield Ohio 45502 both mechanical electrical reasons Commutators much harder mate rial brushes nomally wear away However brushes al lowed wear down completely metal brush arm brush springs begin ride commutator will wear tt will probably become scored motor performance will decline electrical noise due ex cessive sparking likely commutator could permanently ruined avoid problem best look brushes occasionally especially re placeable Some visible through bent holes disassembly necessary inspection Others easily removed exter nally brush holders unscrewing caps Handle brushes carefully cleanly replace same way came out Ive seen other problems brushcommutator area Some motors may begin display noticeable performance drop erratic running no apparent reason often associated excessive brush sparking possibly radio glitches may due inadequate brush pressure though brushes show little wear brush arms spring material lower-cost motors become overheated due motor being overworked some other reson may lose some tension Another effect high heat can com mutator distortion commutator gets out round brush bounce occurs case brushes excellent condition cant job fact Ive seen happen motors no way overworked commutator defective start can seen during break-in unloaded unpropped motor runs erratically can actually feel rotational irregulatiry hand commutator out round lay running motor table can watch twitch Use warranty card should motor defective received Both conditions inadequate brush pressure out-of-round com mutator can appreciated better apply ing some light pressure either brush through vent hole toothpick motor speed picks up smooths out no ticeably chances prob lems exists have relatively new cobalt motor has treated considerable care two occasions far performance suddenly dropped off Aerobatics model just wouldnt its usual tricks Close inspection revealed nothing unusual brushes commutator looked good battery pack etc normal brushes cobalt motor ride square brush guide tubes have coil springs brush pressure Upon re assembling brushes same brush same holder same orientation motor its old self again same thing happened visitor last years Electric Fly guess brushes become little snug guides pressure effectively reduced Perhaps some brush dust clogs guide bit Anyway removing brushes wiping tissue cleaning guide tube dry pipe cleaner does trick sure handle brushes carefully keep fingers off avoid possible con tamination Sometimes above conditions apply symptoms similar motor has run hard resulting high brush heat some brush material may smeared heavily commutator sur face prevent good electrical contact Try cure Take prop off run motor normal battery pack two three minutes Replace prop tached rpm before after may see noticeable improvement possible recommend making note motor/battery performance new after break-in generally note rpm particular prop size make battery voltage time Later theres question about performance data can compared unlike rangechecking radio rechecking under same conditions later date crash hard bump prop prop adaptor can easily bend armature shaft resulting obvious wobble vi bration Sometimes shaft can straight ened prop will run true armature may still wobble due shaft bend behind front bearing also causes brush bounce erratic running Like brushes some higher-quality motors have armature replacements can bought cases such above recourse unless youre ma chine work Sometimes impact can severe enough rear-end bell and/or bearing break get pushed out rearward-driven armature assembly Ive seen few crankshafts glow engines come through backplate too careful use flexible nylon prop and/or prop stop stop prop horizontal position minimize such problems E Bearings Electric motors models have either sleeve bearings ball bearings Usually sleeve bearings selflubricating self-centering motor 400 hts type new owner flew past 500 flights Finally bearing wear caused much noise embarrassed replaced motor about 12 dollars Thats about cost gallon you-know-what Ball bearings found larger and/or costly motors What kind un pleasant contradiction costly motor ball bearings non-replaceable brushes little like car nonreplaceable tires Given choice Im content sleeve bearings small motors Im convinced balls worth added cost kind flying may afford com petitive edge series flying addressed fun sport flying Whatever bearing type never add lu Con tinued page 136 THIS FUEL FEATURES RUST PREVENTION AGENTS ODETERGENTS OLUBRICATION WITH HIGH FLASH POINTS WETHNG AGENTS FOR MORE EFFICIENT AND DEPENDABLE FUEL FLOW OANTI-FOAMING AGENTS TO PREVENT LEAN RUNS KEEPS YOUR ENGINE RUNNING COOL OAN ODORLESS HIGHLY REFINED FUEL CHILDPROOF LIDS Available FAI 5 10 15 25 & 40% Nitro-Methane Contents Formulated synthetic lubricants Also available castor DEALERS WANTED DOMESTIC & OVERSEAS WE EXPORT competition tuel fast becoming THE CHOICE top protesonals ot tirst ro cash product Contact us price structures ordering information Manufacturers Major Brand Distilbutors Model Engines Kits Radios Accessones SUPER K Fuels brand KINGS RADIO CONTROL HOBBIES INTERNATIONAL 3960 West 16 Ave Hlaleah Florida 33012 305 557-2024 October 1983 133 1r specially formulated chemically balanced fuel top petformance minimum engine wear weather condition Electrics/Kopski Continued page 133 brication drop oil might find its way onto commutator surface brush material Thats end Im told F Other motor features Some other things make motor better use model aircraft often include wire set suitable polarized connector terminals easy connections Usually ca pacitors wired brush terminals help suppress electrical noise may otherwise interfere RC operation High-temperature insulation epoxy coat ing windings lacing wires commutator connections keep everything place good features too motors have finely finished bal anced armatures assure smooth vibrationfree operation Motors may have neutral tim ing turn equally well either direction others may have offset timing maximize performance normal di rection propeller use Some motors pack higher power han dling capability small case through use costly very high strength field mag nets such samarium cobalt material feature adds big bucks motor price armature shafts bend just easily sure pay particular attention land ing German Keller motor available flux rings metal bands slip over outside motor can make metal thicker Without case rela tively thin motor works best small props high revs case heavied-up rings motor develps higher torque turn larger props efficiently lower rpm Its like having variety motors 3 Motor size often subject much confusion beginners Its presently cause much ado modeling indus try Opinions vary to specify size classes Eventually some standards will emerge AMA SEAM Society Electric Aircraft Modelers other interested parties sort out best options necessarily simple task Un like gas engine typically char acterized its displacement cubic inches several candidate ways characterize classify electric motors way would measure physical size such armature perhaps overall motor weight Another way de scribe battery instead motor size class determined number and/or kind cells motor battery method used Europe FAt events will interesting see settled Eventually will important have some size designations allow orderly inevitable evolution competitive Elec tric events folks arent quite ready competition yet just trying get started series intended help As youll see some standards would very big help too First lets look what motor size has historically meant largest variety motors country have descriptions sound like gas engine sizes ex ample popular motor size 05 has come mean motor would swing same size prop about same rpm typical glow counterpart Thus 05 example would probably use 6-in diameter 4-in pitch prop would turn prop about same speed glow 049s Similarly electric IS might swine 8-4 prop sounds simple enough isnt Things changing Electric evolving some associated growing pains joys cobalt 05 example can easily out-power 049 glow engineand swing much heftier prop too Its really good ol 05 Other changes occurring too all-time favorites so-called 075 its old self anymore Despite same nomenclature catalog number windings now different long-developed familiarity goes out window least deserves new part number above given purpose confusing Rather illustrates creasine need size class standards reminds us present dynamics Builders Get f Better Start Season Using KIN-CRAFT Quality Line Polyester Resins Micro-Balloon Air-O-Fill Gloves Protective Fiberglass Cloth & Tapes 6 oz Cloth 1 4 & 6 Tapes Custom Cut Cloth Any Length Sandable Primers Thinner Accessories also Dust Masks Gator Grip Contact Cement Applicator Kits Engine Cleaner Oil Kits 2u Ii tj Ilobby Prod U IS Send self-addressed stamped envelope free catalogue discounts Dealer Distributor Inquiries Invited Kin-Craft Mig Ri 2 Box 481E Ashland KY 41101 606 928-4763 136 Model Aviation SUPERwings DIVISION oF HI JOHNSON MODEL PRODUCTS 11015 GLENOAKS BLVD PACOIMA CA 91331 SAILPLANE COMPONENTS CREATE YOUR OWN SUPER GLIDER WING FOAM CORES Floater Thermal & Slope FUSELAGES LUSTROLEEN 2 Meter Standard Open & Scale STAB FOAM CORES Rudder & Fin Cores COVERING MATERIALS White skin & Lustroleen WING RODS Wing Tongue Kits FOR HI JOHNSONS PORTFOLIO PRICE SHEET & ORDER FORM about sailplane construction & design using foam & plastic SEND $250 CHECK OR MO CA RES ADD SALES TAX AMA Clubs Giant Scalers Save 30%Order Direct Buckeye Balsa supplies AAA quality balsa certified aircraft plywood fine kits Aero Composites Double C Mfg Fliteglas Models Fourmost Products Kitty Hawk Models Dave Platt Precision Built Models R/C Kits Mfg VK ModIs Bob Dively Model Aircraft hobby shops Send $1 catalog Price applied first order Minimum Net Order $50 No sh pprng COD charges 216 533 3607 P0 Box 174 Canfield OH 44406 ALL SKEET ONE PIECE AAA GRADE KILN DRIED SANDED TO CLOSE TOLERANCES PED 100% Balsa Sheets36Light 46lb361/8 x 3453/16 sq 173/8 x 11/246 1/16 x 2331/16 x 3491/16 x 4481/4 sq 261/2 x 270 3/32 x 2403/32 x 3563/32x4561/4x3/8 30 1/8 x 2431/8 x 3671/8 x 4663/8 sq 37BalsaTriangles 3/16 x 2493/16 x 376 Sticks 6 1/4 x 2561/4 x 385 ched 40%1/4 x 1/425 3/8 x 3115 ets 423/8 x 3/830 1/16x3371/2 x 31393/32 x 4100 W1/2x1/235 3/32 x 3441/8 x 4108Basswood h Pine3/4x3/445 1/8 x 354BalsaSheets483/16x4120 cks For1 xl55 3/16 x 3621/16 x 3491/4 x 4131 Scale 1/4 x 3733/32 x 358Balsa Sticks36Lite Ply48 5/16x3851/8x3 711/8 x 6150 3/8 x 3883/16 x 3 821/16 x 1/409 1/2 x 31101/4x 33/32 x 1/410Birch Dowels 361/8 x 12300 3/4x31653/8x31241/Bsq.081/8 09 1/8x1/411 3/16113Ply Birch48 1/4141/64x12525 1 x3200 1/2x3155 1/8x1/2181/32x12425 1/16 X 4581/16 x 4763/16 sq.11Sendaddressed1/16 x 12435 3/32 x 4703/32 x 41/4 sq.16 1/8ic4801/8x41/4x1/221stanipedenvelope1/8x12450 3/16 x 4933/16 x 43/8sq.27 logue 1/4x4110 1/4x4134 318x1/232listingall sizesSPlyBirch48 3/32 x 12570 3/8x41653/8x4225 1/2sq.361/8x12585 1/2 x 4225Pine Sticks36 Trailing Edge 3/16 x 12585 NEWBalsa Sheets 30 1/8 sq.13361/4 x 12600 Quarter1/16 x 331 1/8 x 1/416 1/4*132 ScaleSizes3/32x337 1/8x3/820 5/16x11/439 accept Visa Master Card personal checks COD jiandling Charge $3 pay UPS Add $2 COD $3 extra PP SPO FPO 5% tax Texas US currency relatively new area model aviation So advised dont discouraged Some day future will good ol days' Electric new Standards lacking notwithstanding series will help get flying un derstand hows whys meantime consider lonely world df few US suppliers products electric-powered flight Im sure its long lean decade dedication per severance belief future thank stalwai-ts Im convinced major chunk modeldoms future de servedly Without wouldnt reading 4 When get good stuff nearing end Part Two series know readers may getting quite anxious get building flying something Thats quite under standable lets pause put whole Electric thing perspective Its rela tively new unfamiliar mLdelers including some very astute skilled Based inquiries receive subject continues bring far questions readily available answers Now consider popular continuing columns some modeling magazines devoted conventional engines Surely things have use bug enough everyone knows about right Nope Now consider basic arti cles have seen devoted electric motors electric flight batteries electric anything elseall unanswered questions right Look another way know someone flying group whos got together Hes guy experience engines always run just right maintains equipment specialist Helicopter Scale Rubber Com bat whatever guy knows awful lot about modeling general too knows what hes doing has good un derstanding basics uses full advantage series will have plenty to' examples go along its parallel goal convey basic understanding fundamental aspects electric-powered flight time-honored method teachingbasics plus examples Some text some lab work sorta under hat youll soon easily answering understanding such questions what motor needed fly what plane what should weigh assure much flight time Soon Electric products today will become dated will specific examples based dont want series become dated want continue basic value understanding utilization whatever new better prod ucts come along have reasod able acquaintance Elec tric works will have no trouble obtaining first-time continuing success Stay us youll person has together' Electric very anxious let suggest youre following series also keep eye contemporary magazines good source suitable Electric designs have already published MA alone has three four last year articles typically include electric system information design Later series will suggest guidelines motor plane combinations will assure success Also intallation coming As mentioned Part very versatile RC design Spectra can accommo Con tinued page 140 ATTENTION ERS October 1983 137 EPOXY GLASS COWLS FOR NOSEN PICA SIO MORGAN BALSA USA PLA TT CONCEPT FLEET HOSTETLER RCM T-CRAFT SHEBER P177S & SCALE SUPER CUB POKEER O7 BOEING P72 P26 F4B2 P464 SPARROW HA WE GEE BEE MOO r MACBRIEfSS TURBULEAIT CHRISTEN EAGLE BRISIGHELLAS STAROUSTEFf II A SCALE 1381 BABY FLYBABY AIRCAMPER PILOT JUNGMANN 735 SCALE 7/4 SCALE DECATIIALON PIPER PA- TB ft OThERS WHEEL PANTS FOR CITABRIA SrAROUS TER II PIUS SKYBOLT LIBERIYSPORT CHRISTEN EAGLE PBE HAWK STEARMAN STINSON SRB MULLIGAN & OTHERS BRAZED& HEAT-TREATED WIRE GEARS&CABANES LARGE SCALE PLANS AVAILABLE Send $100 latest list supply Modelers fiberglass parts plansWrite call us T & D FIBERGLASS SPECIALTIES 30925 eLOcK GARDEN CITY Mi 48135 PHONE 313 421-6358 r Finally.. 1/3 Scale Realism lightweight highly detailed realistic pilot figure scale R/C model aircraft figure Shown 1/3 scale civilian Seated approximately 125 tall 310 mm weighs 15 ounces comes complete including instructions painting fits 1/3 scale planes including Pitts Eagle Homebuilts ORDER YOURS TODAY Produced byPrice $1995 William M Hawke$200 shipping 7148 Lasting Light Way Columbia MD 21045 Ask dealer order diredt 1/4 scale coming soon L Electrics/Kopski Continued paqe 137 date variety electric power systems planned construction article Next up Part Three will discuss pro pellers electric power motors sole function convert energy stored battery propeller thrust Im sure will amazed just what takes turn prop various props com pare prop change affects flight performance think youll find Part Three enlightening though still fundamental also graphic unique dont think thing like has published before Part Four will devoted bat teries about batteries Installations planes follow Now answer title question good stuff will continue will eventually come together promise As continue challenge series Ive come appreciate its sizeable scope very difficult write compact complete simple Introduction Elec trics regard want thank wife Wilma MA Editor Carl Wheeley Columnist Bill Winter Electric flying friends KRCHerb Dirks John Hickey Heinz Koerner Don LeGower Dan Mittenfor critiquing drafts artworks helpful sugges tions Any questions related part earlier parts series may directed SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 RC Soaring/Pruss Continued page 45 helpful may have noticed skipped Fri days activity did because thats excitement occurred Fridays forecast thin layer four-day weather sandwich However based encouraging figures light winds aver age soaring conditions shutoff time day set 600 pm Published starting time four days 1000 am Troy Lawicki group Sil ver Eagles Soaring Society Michigan first course 1045 Several others followed logged very short flights Further attempts went way until about two oclock shortly after 17 Sailplanes air same time sight Nine working same thermal see 14-foot beau ties gracing same sky Contest Direc tor s reward time frame between 219 228 13 teams entered course included nine top 10 last years event test both Sailplane pilots skills purest form No gimmicks no trick launch equip ment no bad luck due bad draw can claimed protested against year con testants furnished own winches could launch exactly wanted Once air strategy overshadows luck ship capable bridging thermals moderate altitude trade off higher altitude because youll able cover ground once higher what about winds higher altitudes plowed fields plot ted course map just case need seek out hoping thermal being generated need day nature threw just crumb contestants way didnt last long Among gaggle 13 entered course about same time Jim Boh mer MOSS club group won event last year year retrieved model after 33 miles Skip Miller FAST first ever finish course official time managed 56-mile run relaunched logged 99 best effort during meet Six teams made about 20-mile mark Among Ken Bates Kurt Bak Mike McIntyre Ken Shaw MRCS Ann Abbor MI some six teams played lift hopes altitude before stretching down long southern course Bates left pack about half altitude highest plane group looked though wrong move After losing altitude down treetop height plowed field gave plane nudge upward Bates played thermal out new life made around south side course flew westward northbound forecast winds increased south provided team tailwind last half run Meanwhile south erly heading western leg coming down MRCS suddently course themselves Radio reports gave teams progress no question team con ditions favorable completing course question could beat clock well past three-hour mark air 600 pm shutoff nearing Passing last radio check point became very doubtful whether could finish course time rules state distance flown time shutdown will official distance time less seven minutes go still six miles flown radio reports made exciting Saturday sporting event drama moon launch countdown precisely 175930 official watches MRCS touched down com pleting 76 km1472 mile course three hours 32 minutes second time two years Bates company conquered Soarings greatest challenge also second time used makeshift bird year used wing very old Super Esprit parts other planes team Stan Watson Jim Slater Eric Stenson Dave Haertelrepresenting 4-STROKE ENGINE SALE COMPARE & SAVE Os FS 408950 OSFS6012500 OS FS 7514500 OS ES 120T34900 ENYA4O-4C12950 ENYA6O-4C14950 ENYA9O-4C18950 SAITO 308450 SAITO 40-Il9950 SAITO4510950 SAITO 90T29950 TERMS Prepaid check money order Include $250 UPS street address Calif residents add 6% sates tax No credit cards please Allow 2 weeks delivery REDWOOD hobby imports PO BOX 6171 SANTA ROSA CALIF 95401 Sublect stock hand 140 Model Aviation