Half installations topic covered last monthmotor battery radio big items month author looks installation switches connectors fuses wiring etcthe smaller things equally necessary Part 6E Bob Kopski ut - w w YOU MAY WANT review Part 5 go through related some pictures sketches cover mutual areas 1 Switches Generally two common types used electric power systems miniature toggle miniature snap-action switches microswitches Switches used va riety waysmanually servo-driven different things such simple ON OFF operation change speed steps OFF-LO-HI toggle switch easily mounted fuselage external master power con trol toggle may mounted internally actuated through simple servo pushrod arrangement three-position toggle ON-OFF-ON allows OFF-LO HI function Study photos sketches Snap-action switches very useful installations servo-driven func tions Ive using Radio Shack 275-016 lever switch years particularly planes incorporate prop-stop switch very small lightweight can actually doublesticky-foam-taped servo Ive used technique foam tape mounting does tend flow after period time remounting required rigid mounting screws offers advantage re gard Incidentally Radio Shack part has through-holes can carefully tapped 4-40 thread Both Astro Leisure offer heavier-looking microswitch motor control Again illustrations should help scheme never use actuate switch extreme motion control surface servo such elevator Using full up full down move motor switch always seems get flight trouble Having control motor system plane flying near ground downright treacherous also frequently neededan obvious conflict Personally prefer simply install ad ditional channel have fully noninteractive motor control Ive seen trying seemingly simpler technique have abandoned its simple after Switch ratings given voltage current amps sometimes fur ther broken down AC DC practical purposes rating con cern us application current rating Generally life switch given number operations tested specified electrical load before specified degradation occurs minia ture toggles snap-action switches use may rated few amps say three six good job us very rarely fail though com monly control running currents twice motor starting currents several times higher tested operating life use miniature switches would no doubt very poorly compared life rated currentordinary tens hun dreds thousands operations see doesnt really matter too much get tenth switchs usual life thats still operations apt use can feel confident using small switches meet just about common Left assorted small parts described text see glass-barrel fuse holder middle left plastic fuse top oclock position two sizes two-conductor Molex connectors single-conductor crimp-on connectors battery just below plastic fuse Shown three lengths heater-element resistors two kinds toggle switches lever switch toggle switch wires has aluminum tube extension end flattened drilled pushrod Right Fingertip helps us see interchangeable resistor determines LO motor power level Resistor inside fuselage mounted terminal board incooling air flow 58 Model Aviation Above With wing ot Spectra removed looking straight down battery compartment four six cells come view two forwardto rightout sight Air exit holes per pat tern shown last month visible fuselage floor right will goodat spaces between cells Foam blocks take up extra battery compartment area cells can added battery can shifted balance single crimp-on connector set allows adding extra cells have matching connec tions series Wing saddle tape seals off battery air chamber Right Generous cabin area Dan Mittens Taylorcraft permits easy access everything Compare what see what text says Dan could have saved over ounce Note lever switch side servo left battery servos extended arm needs What uncommon need switch Based experience club motor load current somewhere around 14 16 amps begins push bit miniatures described above However such current would also pushing smaller mo tors Bigger better built mo tors such Astro 25 40 cobalts require heftier February 1984 59 Above Hatch removed Spectra reveals lever switch cam wheel collar prop-stop rod switch position can adjusted up down mounting screws slots fuselage side Adjust cam exact timing switching prop-stopping Above Right Miniature toggle switch flat handle pushed pulled servo-actuated pushrod Springs pushrod prevent stall ing servo switch limits John Hickeys Jack Rabbit Right Servo-actuated double pole double throw center off toggle switch provides LO-OFF-HI motor power sequence Dan Gravers Friendly aluminum tube extension carefully epoxied cleaned scored original switch handle tip extension flattened drilled accept clevis case protection against stalling servo servo output CAM OR SERVOARM 0RADIO SHACK 275016 OR SIM NOT USEDNC NO IVJr4Th K9C J B F1 SW] CHARGE JACK REAR VIEW SYSTEM BATTERY POLARIZED CONNECTORS OPTIONAL FUSE OPTIONAL MAIN SWITCH switches Ive successfully used double-pole miniature toggles two switch sections wired parallel control 25 switch rated 5 amps per pole required replacement after about two seasons flying 2 Simple speed controls Motor power can controlled step fashion using servocontrolled three-position toggle switch As shown sketch position toggle puts resistor battery-motor circuit As explained earlier series small drop applied voltage causes substantial power reduction small-value re sistor needed job Such resistor capable carrying motor current may hard find make own simple resistors done using small sections coiled heating element such found older-style electric hot plates able buy replacement nichrome elements hardware store material hard solder use crimp-type terminals resistors As shown microswitch ON lever up option al prop stop retractedI SW2 MICROSWITCH R DAMPING RESISTOR M MOTOR C BRUSH CAPACITOR 001 uF TYPICAL mounted using 4-40 screws blind mount ing nuts plywood former inal board small selection varying length resistors can easily interchanged field achieve desired low-speed per formance sure mount resistor cooling air flow permit touch model structureit will burn 3 Electronic motor controls Electric motors can controlled stop full throttle very smooth fashion using several electronic speed controls pres ently available devices plug receiver output connector just like servo motor control would plug throttle channel Moving throttle stick smoothly varies motor power electronic speed control Ive seen does cause some loss power high end compared motor performance such control percentage basis same motor current power lost fewer-cell batteries batteries having large number cells other words MOTOR ON-OFFDAMPING PROP STOPRADIO SHACK RADIO SHACK271-13C 275-016TAP 4-402 PLACES SWITCH ALUMINUM TUBE TO SERVO N SECURE RED OUTER WELL ADJUST FOLLOWER LOCATION ON ROD SWITCH POSITION ON FUSELAGE SIDE FOR OPTIMUM OPERATION 4-40X1/2 NYLON RE W S FUSELAGE SIDE 1/8 X3/16 SLOTS 2 PLACES MOTOR OFF AS SHOWN\ YELLOW INNER GOLDEN ROD1/16 GOLDEN SULLIVAN 076 RODS WITHROD THREADED ENDS ~~O2O MUSIC WIRE DRILLZ IHAIRPIN MAKE THIS ASSEMBLY WITH HOT STUFF 8 BAKING SODA INNER WIRE ALLOWS SMOOTH BEND STRESS RELIEF WHEN DRILL WHEEL ENGAGING PROP S TAPCOLLAR AS SHOWN PROP STOP IS FORWARD ENGAGED voltage drop controller hurts have low -voltage battery few cells controls least loss seem MOSFETS out put stage type popular among visiting fliers 1983 KRC Electric Fly lost power described above caused part semiconductor switching de vices speed control As result control gets hot again some cooling air over heat-sink plate must Follow manufacturers recommendations stalling device feel good idea have master power switch circuit using electronic motor controls simple toggle switch mounted side fuselage convenient turning motor system power OFF helps assure example some radio glitch wont momentarily activate speed control youre work ing control surface adjustments Ive seen few problems use electronic controls Ill mention Some receivers like being connected motor-battery system connection can cause severe glitching apparent loss range because motor brush noise has easy conductive path receiver some receivers cannot reject kind interference Another problem Ive en countered has apparent up setting overall antenna/counterpoise system receiver simple addition extra stuff connected flight control system adversely affects radio aspects receiver antenna retuning prob ably wont help bit difficult describe easy fix Three rf chokes three controller input leads does trick Chokes about 5 20 microhenries such used various receiver trans mitter circuits good candidates experiences have electronic speed controls other devices electrically connect two systems potential troublemakers well such example may simple elec tronic motor ON-OFF controls with out built-in power regulator re ceiver latter devices permit running radio equipment motor battery designed shut off motor still plenty power left run radio personal preference use separate radio battery accomplish ON-OFF function servo/switch technique described earlier best way avoid problems above use electronic motor controls op ticoupler inputs no hard-wired connection between airborne radio electric power systems though controller plug connected receiver output course problems above common ones believe less likely modem re ceivers Finally no matter what installation consists follow practice physically separating two on-board electrical sys tems Avoid routing receiver wiring espe cially antenna wire near anything 60 Model Aviation TYPICAL ELECTRIC SYSTEM WIRING DIAGRAM power system running motor good noise generator radio static careful tidy installation work will help avoid concern 4 Fuses subject has always interested lot folks KRC Electric Fly Semi nars part primarily interested whether fuse fuse 2 what size 3 what kind As far Im concerned matter mostly personal preference help arrive own choice lets look some considerations purpose fuse electrical system protect costly components equipment inexpensive device used fuse should always located close possible power source just like fuses breakers right power mains residencebefore rest house wiring case fuse should installed wiring close battery Thus thing cant protect against problem battery itself However other problem causes severe high current demand results blown fuse common reasons happening mis-wires shorts either stalled very heavily-loaded motors Thus assuming top-notch wiring job concern would stalled motor have witnessed happen some rea son plane gets snarled some high grass grass tangles stalls prop seconds rising smoke mostly motor brushes windings give up ghost turn crispy critters Eventually insulation system wiring begins melt battery cannot touched because its high temperature Theres lot energy thar cells pardner Generally speaking some form motor ON-OFF control used power can shut off problem observed course theres question like lihood problem occurring first place What comes down pretty much feel about chance youre taking fusing Europeans gen eral seem avoid fuses writers SEAM newsletter argue strongly Personally Ive drifted away use although know sure someday Ill wish fuse What should youre really doubt fuse commonly-used fuse styles pictured Both readily-available auto other stores classic glass tube metal ends type can installed matching fuse holder Radio Shack newer plastic-encased types require slip-on crimp-type wire terminal ends make connection latter parts smaller lighter easier install tuck model As far size goes fuses rated current will blow break con nection popular motors ratings 10 15 amps should quite satisfactory Larger higher-power motors described earlier require higher ratings TYPICAL OFF-LO-HIGH ELECTRIC SYSTEM WIRING DIAGRAM LO OFF HIGH FLATTENED ALUM TUBE I/EPOXY TO SWITCH R 1 M C ARGE JACK REAR VIEW B SYSTEM BATTERY lJ2 POLARIZED CONNECTORS F OPTIONAL FUSE course Some manufacturers provide structions regard Follow Fuses inexpensive can try different ratings youre sure Start lower ratings such 10 amps fuse blows no apparent reason during flight up rating little Unless youre really high-power stuff should no reason go much beyond 20 amps 5 Wiring Some typical system wiring dia grams shown Most electric power sys tems available pre-wired intercon nection harnesses and/or various connectors Its possible cover variation especially available speed controls used general sure follow instructions equipment Some Electric fliers like roll own wiring aspire such undertaking some sugges tions battery packs come pre-wired may want modify assemble own typically use 18-gauge lamp cord zip cord wiring although high-current systems over 12-14 amps long lead lengths warrant heavier wire true wires carrying battery-to-motor current Some other wires such connections separate charge jacks can lighter hook up wire such 20 22 gauge Zip cord always available several colors inexpensive zipped-apart individual wire colors easy convenient keeping track various leads Single-conductor plastic insulated wire also available several sizes colors auto supply stores sure use flexible stranded variety opposed solid-conductor kind cells Ive seen have solder tabs welded cell ends Sometimes may soldered directly together cell cell may used pads wires may easily soldered pays clean straps fine sandpaper SW DOUBLE THROW CENTER OFF SWITCH 3-POSITION R INTERCHANGABLE RESISTER M MOTOR C MOTOR BRUSH CAPACITOR pencil eraser before soldering course always use radio -type solders acid-core types generally solder close cell possible minimize solder strap lengththese arent heavy wire being connected Excess strap length easily cut off Cells massive heat sinks Use sol dering iron both high enough temperature high enough heat capacity allow quick smooth flow solder like tool such Radio Shack 64-2080 handle 64-2082 element 64-2089 tip Avoid use soldering guns vicinity motors extremely strong magnetic field gun transformer may tend de magnetize motor magnets safety battery wiring cells dis charged state Dont soak heat cells Adequate tool heat capacity permits good connection made short-time touch soldering iron careful stripping wire cut strands assure insulation remaining neededsuch wire crosses cell cell Remember case cell negative tenninal around up down cell positive terminal resides small island end Take care cut burn cell outer insulating sleeve may want use smaller soldering tool connections lugs switches connectors Usually solder lugs tight fit 18-gauge larger wire generally tin pre-solder coat both lug stripped wire end lay wire flat against lug reflow solder makes neat adequate joint Sometimes slip some insulating tubing over joint such often done RC connectors Most electric power items made country supplied convenient polar ized cant connect backwards con nectors such made Molex Generally two sizes two-conductor plastic Continued page 62 February 1984 61 revolutionary concept power 1 SV glow plugs model engines used boats cars airplanes NI STARTERITMI uses HeadlockITMI adapter locks onto wont glow plugs start engine Fits Yost pocket comes CIlO charger has LED lights up charging Rechargeable hundreds times gives over hO consecutive starts recharging Available charger Send ad along prepayment receive free shipping handling NI-STARTER$2495 charger Ill OV 220V 12V fast chargerl NI-STARTER$1595 charger Chargers$1295 charger ii 220V orb 2V fast chargeri PLEASE SPECIFY WHICH CHARGER WHEN ORDERINGl 12721 HASKELL LANE BOWIE MARYLAND 207161301464-2260 NEW FOURMOST PRODUCTS FUSELAGE FIXTURE FOURMOST FUSELAGE FIXTURE 5 desrgned ta Astenutieelly align fuselage structures built strings measuring yr eyeballrng Simply slide fear centerine brackets n track ustil alige finrewall tarl vinyl tine bulkheads Clamp fsselagetogetherlightly rubherbands structure wrIl straight track Price 2995 Miter Master Miter Master tour designed usable craftsmae make perfect luiets inn woud accurately sanding pre-setangles squarinafencelAl allowsforprecise9O angles retracts beluw surface Any angle can beset triangular guide using adiacent side cumplemeet ut angle will formed making invaluable fur truss cunstractiun yew cyanuacrylare adhesives require accurately fitted ivints te achieve full strength Minter Master will enable te make naurly FOURMOST PRODUCTS 4040 24th Ave Forest Grove OR 97116 Price $950 Asnentufee bound 503 357-2732 mates have used shown among pictures recently smaller two has become popular connectors available Astro Leisure electron tcs supply houses Another connector style may find use ful single-conductor crimp-on type also pictured require crimping tool proper installation Often 1 wish con nect single wires kind connector connecting plastic fuses mentioned earlier single connectors available already insulated can obtained Radio Shack auto stores hardware stores sure pur chase size suitable 18 16-gauge wire few things should know about both connector types mating fit very tight new often very hard pull needed separate Frequently suddenly let go hands can easily disassemble model wary other hand same con nectors can become quite loose after re peated use happens con nection quality becomes doubtful Fortunately theyre low cost easy replace way some polarized Molex connectors have snap indents purpose being sure stay together catches necessary trim off modeling knife Another connector commonly used purposes mentioned Part 4the charge plug jack parts made Switchcraft available As tro have used years extremely reliable convenient Proper connection polarity shown drawings very helpful con venient flying field fliers use similar charging connectors sometimes neces sary share charging equipment Switchcraft parts common use KRC Now some wiring trivia single 10-in-long conductor 18-gauge lamp cord carrying 10 amperes has voltage drop 0054 volts power dissipation loss 054 watts 20 amps dissipation increases 216 watts wire will probably get warm Use heavier wire case same 10-in-length wire weighs about 013 oz next time somebody flight line acts like knows everything can lay him keep em mind too 6 Prop stops have using prop stops years thanks idea presented Jim Zarehibski Pioneer 15 glider RCM long ago idea prop stop simply locate unpowered prop hQrizontal position landing can fuselage skid prop tip offers distinct advantage fewer broken props importantly fewer bent armature shafts Clearly prop stop almost required model no land ing gear practice prop stop actu Continued page 155 62 Model Aviation 7 N I-STARTER MFG OF NI-STARTER $2495 charger h NEW R/C BOOKLET Answers questions often asked want get started RIG flying PLUS troduces best airplane start GOLDEN FALCON receive copy SEND $200 TO ST CROIX OF PARK FALLS LTD PO Box 279P Park Falls WI 54552 ation standard 22 gauge stranded hook-up wire will adequate Before actually start wiring might want note wiring sketch shows switches appear bottom view next column will have information use resistor shown control box wiring controlling servos speed wire servos some sugges tions insulate control lines flight control handle planes bellcrank system Send items CL Scale Bill Boss 77-06 269th St New Hyde Park NY 11040 Electrics/Kopski "" ~ oaoe 62 ated same servo operates ON OFF switch Refer sketch pictures Parts 2 suggested installation can have vari ations example instead switch being actuated follower prop stop rod switch can directly mounted servo described earlier Also may find some suitable alternative stop-rod material use case sure adjust lengths throws timing prop stop clear prop bet bre switch turns ON switch turns OFF before stop advances prop necessary have small repeatable drag part prop bladethe Great Lakes Model Company PO Box 308 Tawas City Ml 48763 AT-6 SNJ HARVARD Wingspan 63 375 60 Engine 7 lbs Complete List Price $28500 Factory Direct $22800 Michigan residents add 4% salns taa Send SASE fnr Brochare Dealer Inquiries Welcome stop rod does have thrust completely through prop thickness Small motors have three armature poles tend cog ie stop three specific armature positions due pull magnets Mount prop adapter prop stop engages close natural armature resting positions Motors three poles have less tendency cog excep tion some very strong cobalt mag nets prop will tend spin freely case just ease stop prop Sometimes takes little practice adjustment get prop stop repeatedly desired horizontal position persist resistor shown sketch serves purpose braking motor switch goes OFF state resistor instead power switched across stillcoasting motor Without damping re sistor motor prop likely con tinue spinning prop stop withstanding Such coasting armature/prop has con siderable inertiareadily appreciated should engage finger can easily chew up stop rod freewheeling motor its windmill blades acts generator actually develop ing voltage its open terminals resistor forms electrical loada dynamic brakeand limits resulting current surge slow ing stopping generator re LET US KNOW WHERE YOU ARE GOING move please let us know advancesix weeks required change address Attach current MA mailing label check appropriate box mail Subscrip tion Dept Model Aviation 1810 Samuel Morse Dr Reston VA 22090 Check appropriate boxenclosE payment U NEW SuBSCRIPTION U CHANGE OF ADDRESS Non-AMA subscription rates $1800 12 months US possessions elsewhere including G.nada Mexico $2400 US Schools $900 US Libraries $1350 NAME ADDRESS CITY/STATE __________________________________________________ ZIP MODEL AVIATION 1810 SAMUEL MORSE DR RESTON VA 22090 COMPLETE THIS FORM AND ATTACH MAILING LABEL FROM RECENT IssuE 517 362-6078 sistor shown typical valuefrom half twice value usable optimum value varies motor prop plane speed etc may wish try several val ues singular annoyance about such lowvalue resistors availability especially small physical size high wattage rating needed /2 watt plenty Im still looking convenient source Finally prop stops best used directdrive props speed-reduced props gear belt drive cannot stopped easily Fold ing props much better addition protecting both prop prop shaft folders offer considerable aerodynamic drag reductionjust whats needed high-time gliders Next month Part 7 will deal extensively suitable model designs both prin ciple practice Therell some dis cussion construction techniques model size motor size battery size weight flight timesfor sorts models As closing note having referenced sev eral Radio Shack parts supplies have comment Radio Shack has dis quieting practice suddenly dropping items its catalog Items mentioned herein available writing Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 SAFE FLYING IS NO ACCIDENT COMPLETELY FINISHED R/C AIRCRAFT Completely Finished R/ C Aircraft s & Types Radio Engine Only CG Sky riger--63 trainer $22500 Sig Clip Wing J-3 Cah--54 Spon $25000 SEND FOR COMPLETE LIST HOBBY CAPITOL R/C 46 N Oak St Ventura California 93001 FebrUary 1984 155 sIa & Aaaas Han Gal SHaI-Sdy SILICONE 10 foot coils TUBING ID 062 092 125 us POST $/coiI 235 265 325 54t/COIL LARRY DODGE AERO INC 10210 MANNINGSTILLWATER MN 55082
Edition: Model Aviation - 1984/02
Page Numbers: 58, 59, 60, 61, 62, 151
Half installations topic covered last monthmotor battery radio big items month author looks installation switches connectors fuses wiring etcthe smaller things equally necessary Part 6E Bob Kopski ut - w w YOU MAY WANT review Part 5 go through related some pictures sketches cover mutual areas 1 Switches Generally two common types used electric power systems miniature toggle miniature snap-action switches microswitches Switches used va riety waysmanually servo-driven different things such simple ON OFF operation change speed steps OFF-LO-HI toggle switch easily mounted fuselage external master power con trol toggle may mounted internally actuated through simple servo pushrod arrangement three-position toggle ON-OFF-ON allows OFF-LO HI function Study photos sketches Snap-action switches very useful installations servo-driven func tions Ive using Radio Shack 275-016 lever switch years particularly planes incorporate prop-stop switch very small lightweight can actually doublesticky-foam-taped servo Ive used technique foam tape mounting does tend flow after period time remounting required rigid mounting screws offers advantage re gard Incidentally Radio Shack part has through-holes can carefully tapped 4-40 thread Both Astro Leisure offer heavier-looking microswitch motor control Again illustrations should help scheme never use actuate switch extreme motion control surface servo such elevator Using full up full down move motor switch always seems get flight trouble Having control motor system plane flying near ground downright treacherous also frequently neededan obvious conflict Personally prefer simply install ad ditional channel have fully noninteractive motor control Ive seen trying seemingly simpler technique have abandoned its simple after Switch ratings given voltage current amps sometimes fur ther broken down AC DC practical purposes rating con cern us application current rating Generally life switch given number operations tested specified electrical load before specified degradation occurs minia ture toggles snap-action switches use may rated few amps say three six good job us very rarely fail though com monly control running currents twice motor starting currents several times higher tested operating life use miniature switches would no doubt very poorly compared life rated currentordinary tens hun dreds thousands operations see doesnt really matter too much get tenth switchs usual life thats still operations apt use can feel confident using small switches meet just about common Left assorted small parts described text see glass-barrel fuse holder middle left plastic fuse top oclock position two sizes two-conductor Molex connectors single-conductor crimp-on connectors battery just below plastic fuse Shown three lengths heater-element resistors two kinds toggle switches lever switch toggle switch wires has aluminum tube extension end flattened drilled pushrod Right Fingertip helps us see interchangeable resistor determines LO motor power level Resistor inside fuselage mounted terminal board incooling air flow 58 Model Aviation Above With wing ot Spectra removed looking straight down battery compartment four six cells come view two forwardto rightout sight Air exit holes per pat tern shown last month visible fuselage floor right will goodat spaces between cells Foam blocks take up extra battery compartment area cells can added battery can shifted balance single crimp-on connector set allows adding extra cells have matching connec tions series Wing saddle tape seals off battery air chamber Right Generous cabin area Dan Mittens Taylorcraft permits easy access everything Compare what see what text says Dan could have saved over ounce Note lever switch side servo left battery servos extended arm needs What uncommon need switch Based experience club motor load current somewhere around 14 16 amps begins push bit miniatures described above However such current would also pushing smaller mo tors Bigger better built mo tors such Astro 25 40 cobalts require heftier February 1984 59 Above Hatch removed Spectra reveals lever switch cam wheel collar prop-stop rod switch position can adjusted up down mounting screws slots fuselage side Adjust cam exact timing switching prop-stopping Above Right Miniature toggle switch flat handle pushed pulled servo-actuated pushrod Springs pushrod prevent stall ing servo switch limits John Hickeys Jack Rabbit Right Servo-actuated double pole double throw center off toggle switch provides LO-OFF-HI motor power sequence Dan Gravers Friendly aluminum tube extension carefully epoxied cleaned scored original switch handle tip extension flattened drilled accept clevis case protection against stalling servo servo output CAM OR SERVOARM 0RADIO SHACK 275016 OR SIM NOT USEDNC NO IVJr4Th K9C J B F1 SW] CHARGE JACK REAR VIEW SYSTEM BATTERY POLARIZED CONNECTORS OPTIONAL FUSE OPTIONAL MAIN SWITCH switches Ive successfully used double-pole miniature toggles two switch sections wired parallel control 25 switch rated 5 amps per pole required replacement after about two seasons flying 2 Simple speed controls Motor power can controlled step fashion using servocontrolled three-position toggle switch As shown sketch position toggle puts resistor battery-motor circuit As explained earlier series small drop applied voltage causes substantial power reduction small-value re sistor needed job Such resistor capable carrying motor current may hard find make own simple resistors done using small sections coiled heating element such found older-style electric hot plates able buy replacement nichrome elements hardware store material hard solder use crimp-type terminals resistors As shown microswitch ON lever up option al prop stop retractedI SW2 MICROSWITCH R DAMPING RESISTOR M MOTOR C BRUSH CAPACITOR 001 uF TYPICAL mounted using 4-40 screws blind mount ing nuts plywood former inal board small selection varying length resistors can easily interchanged field achieve desired low-speed per formance sure mount resistor cooling air flow permit touch model structureit will burn 3 Electronic motor controls Electric motors can controlled stop full throttle very smooth fashion using several electronic speed controls pres ently available devices plug receiver output connector just like servo motor control would plug throttle channel Moving throttle stick smoothly varies motor power electronic speed control Ive seen does cause some loss power high end compared motor performance such control percentage basis same motor current power lost fewer-cell batteries batteries having large number cells other words MOTOR ON-OFFDAMPING PROP STOPRADIO SHACK RADIO SHACK271-13C 275-016TAP 4-402 PLACES SWITCH ALUMINUM TUBE TO SERVO N SECURE RED OUTER WELL ADJUST FOLLOWER LOCATION ON ROD SWITCH POSITION ON FUSELAGE SIDE FOR OPTIMUM OPERATION 4-40X1/2 NYLON RE W S FUSELAGE SIDE 1/8 X3/16 SLOTS 2 PLACES MOTOR OFF AS SHOWN\ YELLOW INNER GOLDEN ROD1/16 GOLDEN SULLIVAN 076 RODS WITHROD THREADED ENDS ~~O2O MUSIC WIRE DRILLZ IHAIRPIN MAKE THIS ASSEMBLY WITH HOT STUFF 8 BAKING SODA INNER WIRE ALLOWS SMOOTH BEND STRESS RELIEF WHEN DRILL WHEEL ENGAGING PROP S TAPCOLLAR AS SHOWN PROP STOP IS FORWARD ENGAGED voltage drop controller hurts have low -voltage battery few cells controls least loss seem MOSFETS out put stage type popular among visiting fliers 1983 KRC Electric Fly lost power described above caused part semiconductor switching de vices speed control As result control gets hot again some cooling air over heat-sink plate must Follow manufacturers recommendations stalling device feel good idea have master power switch circuit using electronic motor controls simple toggle switch mounted side fuselage convenient turning motor system power OFF helps assure example some radio glitch wont momentarily activate speed control youre work ing control surface adjustments Ive seen few problems use electronic controls Ill mention Some receivers like being connected motor-battery system connection can cause severe glitching apparent loss range because motor brush noise has easy conductive path receiver some receivers cannot reject kind interference Another problem Ive en countered has apparent up setting overall antenna/counterpoise system receiver simple addition extra stuff connected flight control system adversely affects radio aspects receiver antenna retuning prob ably wont help bit difficult describe easy fix Three rf chokes three controller input leads does trick Chokes about 5 20 microhenries such used various receiver trans mitter circuits good candidates experiences have electronic speed controls other devices electrically connect two systems potential troublemakers well such example may simple elec tronic motor ON-OFF controls with out built-in power regulator re ceiver latter devices permit running radio equipment motor battery designed shut off motor still plenty power left run radio personal preference use separate radio battery accomplish ON-OFF function servo/switch technique described earlier best way avoid problems above use electronic motor controls op ticoupler inputs no hard-wired connection between airborne radio electric power systems though controller plug connected receiver output course problems above common ones believe less likely modem re ceivers Finally no matter what installation consists follow practice physically separating two on-board electrical sys tems Avoid routing receiver wiring espe cially antenna wire near anything 60 Model Aviation TYPICAL ELECTRIC SYSTEM WIRING DIAGRAM power system running motor good noise generator radio static careful tidy installation work will help avoid concern 4 Fuses subject has always interested lot folks KRC Electric Fly Semi nars part primarily interested whether fuse fuse 2 what size 3 what kind As far Im concerned matter mostly personal preference help arrive own choice lets look some considerations purpose fuse electrical system protect costly components equipment inexpensive device used fuse should always located close possible power source just like fuses breakers right power mains residencebefore rest house wiring case fuse should installed wiring close battery Thus thing cant protect against problem battery itself However other problem causes severe high current demand results blown fuse common reasons happening mis-wires shorts either stalled very heavily-loaded motors Thus assuming top-notch wiring job concern would stalled motor have witnessed happen some rea son plane gets snarled some high grass grass tangles stalls prop seconds rising smoke mostly motor brushes windings give up ghost turn crispy critters Eventually insulation system wiring begins melt battery cannot touched because its high temperature Theres lot energy thar cells pardner Generally speaking some form motor ON-OFF control used power can shut off problem observed course theres question like lihood problem occurring first place What comes down pretty much feel about chance youre taking fusing Europeans gen eral seem avoid fuses writers SEAM newsletter argue strongly Personally Ive drifted away use although know sure someday Ill wish fuse What should youre really doubt fuse commonly-used fuse styles pictured Both readily-available auto other stores classic glass tube metal ends type can installed matching fuse holder Radio Shack newer plastic-encased types require slip-on crimp-type wire terminal ends make connection latter parts smaller lighter easier install tuck model As far size goes fuses rated current will blow break con nection popular motors ratings 10 15 amps should quite satisfactory Larger higher-power motors described earlier require higher ratings TYPICAL OFF-LO-HIGH ELECTRIC SYSTEM WIRING DIAGRAM LO OFF HIGH FLATTENED ALUM TUBE I/EPOXY TO SWITCH R 1 M C ARGE JACK REAR VIEW B SYSTEM BATTERY lJ2 POLARIZED CONNECTORS F OPTIONAL FUSE course Some manufacturers provide structions regard Follow Fuses inexpensive can try different ratings youre sure Start lower ratings such 10 amps fuse blows no apparent reason during flight up rating little Unless youre really high-power stuff should no reason go much beyond 20 amps 5 Wiring Some typical system wiring dia grams shown Most electric power sys tems available pre-wired intercon nection harnesses and/or various connectors Its possible cover variation especially available speed controls used general sure follow instructions equipment Some Electric fliers like roll own wiring aspire such undertaking some sugges tions battery packs come pre-wired may want modify assemble own typically use 18-gauge lamp cord zip cord wiring although high-current systems over 12-14 amps long lead lengths warrant heavier wire true wires carrying battery-to-motor current Some other wires such connections separate charge jacks can lighter hook up wire such 20 22 gauge Zip cord always available several colors inexpensive zipped-apart individual wire colors easy convenient keeping track various leads Single-conductor plastic insulated wire also available several sizes colors auto supply stores sure use flexible stranded variety opposed solid-conductor kind cells Ive seen have solder tabs welded cell ends Sometimes may soldered directly together cell cell may used pads wires may easily soldered pays clean straps fine sandpaper SW DOUBLE THROW CENTER OFF SWITCH 3-POSITION R INTERCHANGABLE RESISTER M MOTOR C MOTOR BRUSH CAPACITOR pencil eraser before soldering course always use radio -type solders acid-core types generally solder close cell possible minimize solder strap lengththese arent heavy wire being connected Excess strap length easily cut off Cells massive heat sinks Use sol dering iron both high enough temperature high enough heat capacity allow quick smooth flow solder like tool such Radio Shack 64-2080 handle 64-2082 element 64-2089 tip Avoid use soldering guns vicinity motors extremely strong magnetic field gun transformer may tend de magnetize motor magnets safety battery wiring cells dis charged state Dont soak heat cells Adequate tool heat capacity permits good connection made short-time touch soldering iron careful stripping wire cut strands assure insulation remaining neededsuch wire crosses cell cell Remember case cell negative tenninal around up down cell positive terminal resides small island end Take care cut burn cell outer insulating sleeve may want use smaller soldering tool connections lugs switches connectors Usually solder lugs tight fit 18-gauge larger wire generally tin pre-solder coat both lug stripped wire end lay wire flat against lug reflow solder makes neat adequate joint Sometimes slip some insulating tubing over joint such often done RC connectors Most electric power items made country supplied convenient polar ized cant connect backwards con nectors such made Molex Generally two sizes two-conductor plastic Continued page 62 February 1984 61 revolutionary concept power 1 SV glow plugs model engines used boats cars airplanes NI STARTERITMI uses HeadlockITMI adapter locks onto wont glow plugs start engine Fits Yost pocket comes CIlO charger has LED lights up charging Rechargeable hundreds times gives over hO consecutive starts recharging Available charger Send ad along prepayment receive free shipping handling NI-STARTER$2495 charger Ill OV 220V 12V fast chargerl NI-STARTER$1595 charger Chargers$1295 charger ii 220V orb 2V fast chargeri PLEASE SPECIFY WHICH CHARGER WHEN ORDERINGl 12721 HASKELL LANE BOWIE MARYLAND 207161301464-2260 NEW FOURMOST PRODUCTS FUSELAGE FIXTURE FOURMOST FUSELAGE FIXTURE 5 desrgned ta Astenutieelly align fuselage structures built strings measuring yr eyeballrng Simply slide fear centerine brackets n track ustil alige finrewall tarl vinyl tine bulkheads Clamp fsselagetogetherlightly rubherbands structure wrIl straight track Price 2995 Miter Master Miter Master tour designed usable craftsmae make perfect luiets inn woud accurately sanding pre-setangles squarinafencelAl allowsforprecise9O angles retracts beluw surface Any angle can beset triangular guide using adiacent side cumplemeet ut angle will formed making invaluable fur truss cunstractiun yew cyanuacrylare adhesives require accurately fitted ivints te achieve full strength Minter Master will enable te make naurly FOURMOST PRODUCTS 4040 24th Ave Forest Grove OR 97116 Price $950 Asnentufee bound 503 357-2732 mates have used shown among pictures recently smaller two has become popular connectors available Astro Leisure electron tcs supply houses Another connector style may find use ful single-conductor crimp-on type also pictured require crimping tool proper installation Often 1 wish con nect single wires kind connector connecting plastic fuses mentioned earlier single connectors available already insulated can obtained Radio Shack auto stores hardware stores sure pur chase size suitable 18 16-gauge wire few things should know about both connector types mating fit very tight new often very hard pull needed separate Frequently suddenly let go hands can easily disassemble model wary other hand same con nectors can become quite loose after re peated use happens con nection quality becomes doubtful Fortunately theyre low cost easy replace way some polarized Molex connectors have snap indents purpose being sure stay together catches necessary trim off modeling knife Another connector commonly used purposes mentioned Part 4the charge plug jack parts made Switchcraft available As tro have used years extremely reliable convenient Proper connection polarity shown drawings very helpful con venient flying field fliers use similar charging connectors sometimes neces sary share charging equipment Switchcraft parts common use KRC Now some wiring trivia single 10-in-long conductor 18-gauge lamp cord carrying 10 amperes has voltage drop 0054 volts power dissipation loss 054 watts 20 amps dissipation increases 216 watts wire will probably get warm Use heavier wire case same 10-in-length wire weighs about 013 oz next time somebody flight line acts like knows everything can lay him keep em mind too 6 Prop stops have using prop stops years thanks idea presented Jim Zarehibski Pioneer 15 glider RCM long ago idea prop stop simply locate unpowered prop hQrizontal position landing can fuselage skid prop tip offers distinct advantage fewer broken props importantly fewer bent armature shafts Clearly prop stop almost required model no land ing gear practice prop stop actu Continued page 155 62 Model Aviation 7 N I-STARTER MFG OF NI-STARTER $2495 charger h NEW R/C BOOKLET Answers questions often asked want get started RIG flying PLUS troduces best airplane start GOLDEN FALCON receive copy SEND $200 TO ST CROIX OF PARK FALLS LTD PO Box 279P Park Falls WI 54552 ation standard 22 gauge stranded hook-up wire will adequate Before actually start wiring might want note wiring sketch shows switches appear bottom view next column will have information use resistor shown control box wiring controlling servos speed wire servos some sugges tions insulate control lines flight control handle planes bellcrank system Send items CL Scale Bill Boss 77-06 269th St New Hyde Park NY 11040 Electrics/Kopski "" ~ oaoe 62 ated same servo operates ON OFF switch Refer sketch pictures Parts 2 suggested installation can have vari ations example instead switch being actuated follower prop stop rod switch can directly mounted servo described earlier Also may find some suitable alternative stop-rod material use case sure adjust lengths throws timing prop stop clear prop bet bre switch turns ON switch turns OFF before stop advances prop necessary have small repeatable drag part prop bladethe Great Lakes Model Company PO Box 308 Tawas City Ml 48763 AT-6 SNJ HARVARD Wingspan 63 375 60 Engine 7 lbs Complete List Price $28500 Factory Direct $22800 Michigan residents add 4% salns taa Send SASE fnr Brochare Dealer Inquiries Welcome stop rod does have thrust completely through prop thickness Small motors have three armature poles tend cog ie stop three specific armature positions due pull magnets Mount prop adapter prop stop engages close natural armature resting positions Motors three poles have less tendency cog excep tion some very strong cobalt mag nets prop will tend spin freely case just ease stop prop Sometimes takes little practice adjustment get prop stop repeatedly desired horizontal position persist resistor shown sketch serves purpose braking motor switch goes OFF state resistor instead power switched across stillcoasting motor Without damping re sistor motor prop likely con tinue spinning prop stop withstanding Such coasting armature/prop has con siderable inertiareadily appreciated should engage finger can easily chew up stop rod freewheeling motor its windmill blades acts generator actually develop ing voltage its open terminals resistor forms electrical loada dynamic brakeand limits resulting current surge slow ing stopping generator re LET US KNOW WHERE YOU ARE GOING move please let us know advancesix weeks required change address Attach current MA mailing label check appropriate box mail Subscrip tion Dept Model Aviation 1810 Samuel Morse Dr Reston VA 22090 Check appropriate boxenclosE payment U NEW SuBSCRIPTION U CHANGE OF ADDRESS Non-AMA subscription rates $1800 12 months US possessions elsewhere including G.nada Mexico $2400 US Schools $900 US Libraries $1350 NAME ADDRESS CITY/STATE __________________________________________________ ZIP MODEL AVIATION 1810 SAMUEL MORSE DR RESTON VA 22090 COMPLETE THIS FORM AND ATTACH MAILING LABEL FROM RECENT IssuE 517 362-6078 sistor shown typical valuefrom half twice value usable optimum value varies motor prop plane speed etc may wish try several val ues singular annoyance about such lowvalue resistors availability especially small physical size high wattage rating needed /2 watt plenty Im still looking convenient source Finally prop stops best used directdrive props speed-reduced props gear belt drive cannot stopped easily Fold ing props much better addition protecting both prop prop shaft folders offer considerable aerodynamic drag reductionjust whats needed high-time gliders Next month Part 7 will deal extensively suitable model designs both prin ciple practice Therell some dis cussion construction techniques model size motor size battery size weight flight timesfor sorts models As closing note having referenced sev eral Radio Shack parts supplies have comment Radio Shack has dis quieting practice suddenly dropping items its catalog Items mentioned herein available writing Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 SAFE FLYING IS NO ACCIDENT COMPLETELY FINISHED R/C AIRCRAFT Completely Finished R/ C Aircraft s & Types Radio Engine Only CG Sky riger--63 trainer $22500 Sig Clip Wing J-3 Cah--54 Spon $25000 SEND FOR COMPLETE LIST HOBBY CAPITOL R/C 46 N Oak St Ventura California 93001 FebrUary 1984 155 sIa & Aaaas Han Gal SHaI-Sdy SILICONE 10 foot coils TUBING ID 062 092 125 us POST $/coiI 235 265 325 54t/COIL LARRY DODGE AERO INC 10210 MANNINGSTILLWATER MN 55082
Edition: Model Aviation - 1984/02
Page Numbers: 58, 59, 60, 61, 62, 151
Half installations topic covered last monthmotor battery radio big items month author looks installation switches connectors fuses wiring etcthe smaller things equally necessary Part 6E Bob Kopski ut - w w YOU MAY WANT review Part 5 go through related some pictures sketches cover mutual areas 1 Switches Generally two common types used electric power systems miniature toggle miniature snap-action switches microswitches Switches used va riety waysmanually servo-driven different things such simple ON OFF operation change speed steps OFF-LO-HI toggle switch easily mounted fuselage external master power con trol toggle may mounted internally actuated through simple servo pushrod arrangement three-position toggle ON-OFF-ON allows OFF-LO HI function Study photos sketches Snap-action switches very useful installations servo-driven func tions Ive using Radio Shack 275-016 lever switch years particularly planes incorporate prop-stop switch very small lightweight can actually doublesticky-foam-taped servo Ive used technique foam tape mounting does tend flow after period time remounting required rigid mounting screws offers advantage re gard Incidentally Radio Shack part has through-holes can carefully tapped 4-40 thread Both Astro Leisure offer heavier-looking microswitch motor control Again illustrations should help scheme never use actuate switch extreme motion control surface servo such elevator Using full up full down move motor switch always seems get flight trouble Having control motor system plane flying near ground downright treacherous also frequently neededan obvious conflict Personally prefer simply install ad ditional channel have fully noninteractive motor control Ive seen trying seemingly simpler technique have abandoned its simple after Switch ratings given voltage current amps sometimes fur ther broken down AC DC practical purposes rating con cern us application current rating Generally life switch given number operations tested specified electrical load before specified degradation occurs minia ture toggles snap-action switches use may rated few amps say three six good job us very rarely fail though com monly control running currents twice motor starting currents several times higher tested operating life use miniature switches would no doubt very poorly compared life rated currentordinary tens hun dreds thousands operations see doesnt really matter too much get tenth switchs usual life thats still operations apt use can feel confident using small switches meet just about common Left assorted small parts described text see glass-barrel fuse holder middle left plastic fuse top oclock position two sizes two-conductor Molex connectors single-conductor crimp-on connectors battery just below plastic fuse Shown three lengths heater-element resistors two kinds toggle switches lever switch toggle switch wires has aluminum tube extension end flattened drilled pushrod Right Fingertip helps us see interchangeable resistor determines LO motor power level Resistor inside fuselage mounted terminal board incooling air flow 58 Model Aviation Above With wing ot Spectra removed looking straight down battery compartment four six cells come view two forwardto rightout sight Air exit holes per pat tern shown last month visible fuselage floor right will goodat spaces between cells Foam blocks take up extra battery compartment area cells can added battery can shifted balance single crimp-on connector set allows adding extra cells have matching connec tions series Wing saddle tape seals off battery air chamber Right Generous cabin area Dan Mittens Taylorcraft permits easy access everything Compare what see what text says Dan could have saved over ounce Note lever switch side servo left battery servos extended arm needs What uncommon need switch Based experience club motor load current somewhere around 14 16 amps begins push bit miniatures described above However such current would also pushing smaller mo tors Bigger better built mo tors such Astro 25 40 cobalts require heftier February 1984 59 Above Hatch removed Spectra reveals lever switch cam wheel collar prop-stop rod switch position can adjusted up down mounting screws slots fuselage side Adjust cam exact timing switching prop-stopping Above Right Miniature toggle switch flat handle pushed pulled servo-actuated pushrod Springs pushrod prevent stall ing servo switch limits John Hickeys Jack Rabbit Right Servo-actuated double pole double throw center off toggle switch provides LO-OFF-HI motor power sequence Dan Gravers Friendly aluminum tube extension carefully epoxied cleaned scored original switch handle tip extension flattened drilled accept clevis case protection against stalling servo servo output CAM OR SERVOARM 0RADIO SHACK 275016 OR SIM NOT USEDNC NO IVJr4Th K9C J B F1 SW] CHARGE JACK REAR VIEW SYSTEM BATTERY POLARIZED CONNECTORS OPTIONAL FUSE OPTIONAL MAIN SWITCH switches Ive successfully used double-pole miniature toggles two switch sections wired parallel control 25 switch rated 5 amps per pole required replacement after about two seasons flying 2 Simple speed controls Motor power can controlled step fashion using servocontrolled three-position toggle switch As shown sketch position toggle puts resistor battery-motor circuit As explained earlier series small drop applied voltage causes substantial power reduction small-value re sistor needed job Such resistor capable carrying motor current may hard find make own simple resistors done using small sections coiled heating element such found older-style electric hot plates able buy replacement nichrome elements hardware store material hard solder use crimp-type terminals resistors As shown microswitch ON lever up option al prop stop retractedI SW2 MICROSWITCH R DAMPING RESISTOR M MOTOR C BRUSH CAPACITOR 001 uF TYPICAL mounted using 4-40 screws blind mount ing nuts plywood former inal board small selection varying length resistors can easily interchanged field achieve desired low-speed per formance sure mount resistor cooling air flow permit touch model structureit will burn 3 Electronic motor controls Electric motors can controlled stop full throttle very smooth fashion using several electronic speed controls pres ently available devices plug receiver output connector just like servo motor control would plug throttle channel Moving throttle stick smoothly varies motor power electronic speed control Ive seen does cause some loss power high end compared motor performance such control percentage basis same motor current power lost fewer-cell batteries batteries having large number cells other words MOTOR ON-OFFDAMPING PROP STOPRADIO SHACK RADIO SHACK271-13C 275-016TAP 4-402 PLACES SWITCH ALUMINUM TUBE TO SERVO N SECURE RED OUTER WELL ADJUST FOLLOWER LOCATION ON ROD SWITCH POSITION ON FUSELAGE SIDE FOR OPTIMUM OPERATION 4-40X1/2 NYLON RE W S FUSELAGE SIDE 1/8 X3/16 SLOTS 2 PLACES MOTOR OFF AS SHOWN\ YELLOW INNER GOLDEN ROD1/16 GOLDEN SULLIVAN 076 RODS WITHROD THREADED ENDS ~~O2O MUSIC WIRE DRILLZ IHAIRPIN MAKE THIS ASSEMBLY WITH HOT STUFF 8 BAKING SODA INNER WIRE ALLOWS SMOOTH BEND STRESS RELIEF WHEN DRILL WHEEL ENGAGING PROP S TAPCOLLAR AS SHOWN PROP STOP IS FORWARD ENGAGED voltage drop controller hurts have low -voltage battery few cells controls least loss seem MOSFETS out put stage type popular among visiting fliers 1983 KRC Electric Fly lost power described above caused part semiconductor switching de vices speed control As result control gets hot again some cooling air over heat-sink plate must Follow manufacturers recommendations stalling device feel good idea have master power switch circuit using electronic motor controls simple toggle switch mounted side fuselage convenient turning motor system power OFF helps assure example some radio glitch wont momentarily activate speed control youre work ing control surface adjustments Ive seen few problems use electronic controls Ill mention Some receivers like being connected motor-battery system connection can cause severe glitching apparent loss range because motor brush noise has easy conductive path receiver some receivers cannot reject kind interference Another problem Ive en countered has apparent up setting overall antenna/counterpoise system receiver simple addition extra stuff connected flight control system adversely affects radio aspects receiver antenna retuning prob ably wont help bit difficult describe easy fix Three rf chokes three controller input leads does trick Chokes about 5 20 microhenries such used various receiver trans mitter circuits good candidates experiences have electronic speed controls other devices electrically connect two systems potential troublemakers well such example may simple elec tronic motor ON-OFF controls with out built-in power regulator re ceiver latter devices permit running radio equipment motor battery designed shut off motor still plenty power left run radio personal preference use separate radio battery accomplish ON-OFF function servo/switch technique described earlier best way avoid problems above use electronic motor controls op ticoupler inputs no hard-wired connection between airborne radio electric power systems though controller plug connected receiver output course problems above common ones believe less likely modem re ceivers Finally no matter what installation consists follow practice physically separating two on-board electrical sys tems Avoid routing receiver wiring espe cially antenna wire near anything 60 Model Aviation TYPICAL ELECTRIC SYSTEM WIRING DIAGRAM power system running motor good noise generator radio static careful tidy installation work will help avoid concern 4 Fuses subject has always interested lot folks KRC Electric Fly Semi nars part primarily interested whether fuse fuse 2 what size 3 what kind As far Im concerned matter mostly personal preference help arrive own choice lets look some considerations purpose fuse electrical system protect costly components equipment inexpensive device used fuse should always located close possible power source just like fuses breakers right power mains residencebefore rest house wiring case fuse should installed wiring close battery Thus thing cant protect against problem battery itself However other problem causes severe high current demand results blown fuse common reasons happening mis-wires shorts either stalled very heavily-loaded motors Thus assuming top-notch wiring job concern would stalled motor have witnessed happen some rea son plane gets snarled some high grass grass tangles stalls prop seconds rising smoke mostly motor brushes windings give up ghost turn crispy critters Eventually insulation system wiring begins melt battery cannot touched because its high temperature Theres lot energy thar cells pardner Generally speaking some form motor ON-OFF control used power can shut off problem observed course theres question like lihood problem occurring first place What comes down pretty much feel about chance youre taking fusing Europeans gen eral seem avoid fuses writers SEAM newsletter argue strongly Personally Ive drifted away use although know sure someday Ill wish fuse What should youre really doubt fuse commonly-used fuse styles pictured Both readily-available auto other stores classic glass tube metal ends type can installed matching fuse holder Radio Shack newer plastic-encased types require slip-on crimp-type wire terminal ends make connection latter parts smaller lighter easier install tuck model As far size goes fuses rated current will blow break con nection popular motors ratings 10 15 amps should quite satisfactory Larger higher-power motors described earlier require higher ratings TYPICAL OFF-LO-HIGH ELECTRIC SYSTEM WIRING DIAGRAM LO OFF HIGH FLATTENED ALUM TUBE I/EPOXY TO SWITCH R 1 M C ARGE JACK REAR VIEW B SYSTEM BATTERY lJ2 POLARIZED CONNECTORS F OPTIONAL FUSE course Some manufacturers provide structions regard Follow Fuses inexpensive can try different ratings youre sure Start lower ratings such 10 amps fuse blows no apparent reason during flight up rating little Unless youre really high-power stuff should no reason go much beyond 20 amps 5 Wiring Some typical system wiring dia grams shown Most electric power sys tems available pre-wired intercon nection harnesses and/or various connectors Its possible cover variation especially available speed controls used general sure follow instructions equipment Some Electric fliers like roll own wiring aspire such undertaking some sugges tions battery packs come pre-wired may want modify assemble own typically use 18-gauge lamp cord zip cord wiring although high-current systems over 12-14 amps long lead lengths warrant heavier wire true wires carrying battery-to-motor current Some other wires such connections separate charge jacks can lighter hook up wire such 20 22 gauge Zip cord always available several colors inexpensive zipped-apart individual wire colors easy convenient keeping track various leads Single-conductor plastic insulated wire also available several sizes colors auto supply stores sure use flexible stranded variety opposed solid-conductor kind cells Ive seen have solder tabs welded cell ends Sometimes may soldered directly together cell cell may used pads wires may easily soldered pays clean straps fine sandpaper SW DOUBLE THROW CENTER OFF SWITCH 3-POSITION R INTERCHANGABLE RESISTER M MOTOR C MOTOR BRUSH CAPACITOR pencil eraser before soldering course always use radio -type solders acid-core types generally solder close cell possible minimize solder strap lengththese arent heavy wire being connected Excess strap length easily cut off Cells massive heat sinks Use sol dering iron both high enough temperature high enough heat capacity allow quick smooth flow solder like tool such Radio Shack 64-2080 handle 64-2082 element 64-2089 tip Avoid use soldering guns vicinity motors extremely strong magnetic field gun transformer may tend de magnetize motor magnets safety battery wiring cells dis charged state Dont soak heat cells Adequate tool heat capacity permits good connection made short-time touch soldering iron careful stripping wire cut strands assure insulation remaining neededsuch wire crosses cell cell Remember case cell negative tenninal around up down cell positive terminal resides small island end Take care cut burn cell outer insulating sleeve may want use smaller soldering tool connections lugs switches connectors Usually solder lugs tight fit 18-gauge larger wire generally tin pre-solder coat both lug stripped wire end lay wire flat against lug reflow solder makes neat adequate joint Sometimes slip some insulating tubing over joint such often done RC connectors Most electric power items made country supplied convenient polar ized cant connect backwards con nectors such made Molex Generally two sizes two-conductor plastic Continued page 62 February 1984 61 revolutionary concept power 1 SV glow plugs model engines used boats cars airplanes NI STARTERITMI uses HeadlockITMI adapter locks onto wont glow plugs start engine Fits Yost pocket comes CIlO charger has LED lights up charging Rechargeable hundreds times gives over hO consecutive starts recharging Available charger Send ad along prepayment receive free shipping handling NI-STARTER$2495 charger Ill OV 220V 12V fast chargerl NI-STARTER$1595 charger Chargers$1295 charger ii 220V orb 2V fast chargeri PLEASE SPECIFY WHICH CHARGER WHEN ORDERINGl 12721 HASKELL LANE BOWIE MARYLAND 207161301464-2260 NEW FOURMOST PRODUCTS FUSELAGE FIXTURE FOURMOST FUSELAGE FIXTURE 5 desrgned ta Astenutieelly align fuselage structures built strings measuring yr eyeballrng Simply slide fear centerine brackets n track ustil alige finrewall tarl vinyl tine bulkheads Clamp fsselagetogetherlightly rubherbands structure wrIl straight track Price 2995 Miter Master Miter Master tour designed usable craftsmae make perfect luiets inn woud accurately sanding pre-setangles squarinafencelAl allowsforprecise9O angles retracts beluw surface Any angle can beset triangular guide using adiacent side cumplemeet ut angle will formed making invaluable fur truss cunstractiun yew cyanuacrylare adhesives require accurately fitted ivints te achieve full strength Minter Master will enable te make naurly FOURMOST PRODUCTS 4040 24th Ave Forest Grove OR 97116 Price $950 Asnentufee bound 503 357-2732 mates have used shown among pictures recently smaller two has become popular connectors available Astro Leisure electron tcs supply houses Another connector style may find use ful single-conductor crimp-on type also pictured require crimping tool proper installation Often 1 wish con nect single wires kind connector connecting plastic fuses mentioned earlier single connectors available already insulated can obtained Radio Shack auto stores hardware stores sure pur chase size suitable 18 16-gauge wire few things should know about both connector types mating fit very tight new often very hard pull needed separate Frequently suddenly let go hands can easily disassemble model wary other hand same con nectors can become quite loose after re peated use happens con nection quality becomes doubtful Fortunately theyre low cost easy replace way some polarized Molex connectors have snap indents purpose being sure stay together catches necessary trim off modeling knife Another connector commonly used purposes mentioned Part 4the charge plug jack parts made Switchcraft available As tro have used years extremely reliable convenient Proper connection polarity shown drawings very helpful con venient flying field fliers use similar charging connectors sometimes neces sary share charging equipment Switchcraft parts common use KRC Now some wiring trivia single 10-in-long conductor 18-gauge lamp cord carrying 10 amperes has voltage drop 0054 volts power dissipation loss 054 watts 20 amps dissipation increases 216 watts wire will probably get warm Use heavier wire case same 10-in-length wire weighs about 013 oz next time somebody flight line acts like knows everything can lay him keep em mind too 6 Prop stops have using prop stops years thanks idea presented Jim Zarehibski Pioneer 15 glider RCM long ago idea prop stop simply locate unpowered prop hQrizontal position landing can fuselage skid prop tip offers distinct advantage fewer broken props importantly fewer bent armature shafts Clearly prop stop almost required model no land ing gear practice prop stop actu Continued page 155 62 Model Aviation 7 N I-STARTER MFG OF NI-STARTER $2495 charger h NEW R/C BOOKLET Answers questions often asked want get started RIG flying PLUS troduces best airplane start GOLDEN FALCON receive copy SEND $200 TO ST CROIX OF PARK FALLS LTD PO Box 279P Park Falls WI 54552 ation standard 22 gauge stranded hook-up wire will adequate Before actually start wiring might want note wiring sketch shows switches appear bottom view next column will have information use resistor shown control box wiring controlling servos speed wire servos some sugges tions insulate control lines flight control handle planes bellcrank system Send items CL Scale Bill Boss 77-06 269th St New Hyde Park NY 11040 Electrics/Kopski "" ~ oaoe 62 ated same servo operates ON OFF switch Refer sketch pictures Parts 2 suggested installation can have vari ations example instead switch being actuated follower prop stop rod switch can directly mounted servo described earlier Also may find some suitable alternative stop-rod material use case sure adjust lengths throws timing prop stop clear prop bet bre switch turns ON switch turns OFF before stop advances prop necessary have small repeatable drag part prop bladethe Great Lakes Model Company PO Box 308 Tawas City Ml 48763 AT-6 SNJ HARVARD Wingspan 63 375 60 Engine 7 lbs Complete List Price $28500 Factory Direct $22800 Michigan residents add 4% salns taa Send SASE fnr Brochare Dealer Inquiries Welcome stop rod does have thrust completely through prop thickness Small motors have three armature poles tend cog ie stop three specific armature positions due pull magnets Mount prop adapter prop stop engages close natural armature resting positions Motors three poles have less tendency cog excep tion some very strong cobalt mag nets prop will tend spin freely case just ease stop prop Sometimes takes little practice adjustment get prop stop repeatedly desired horizontal position persist resistor shown sketch serves purpose braking motor switch goes OFF state resistor instead power switched across stillcoasting motor Without damping re sistor motor prop likely con tinue spinning prop stop withstanding Such coasting armature/prop has con siderable inertiareadily appreciated should engage finger can easily chew up stop rod freewheeling motor its windmill blades acts generator actually develop ing voltage its open terminals resistor forms electrical loada dynamic brakeand limits resulting current surge slow ing stopping generator re LET US KNOW WHERE YOU ARE GOING move please let us know advancesix weeks required change address Attach current MA mailing label check appropriate box mail Subscrip tion Dept Model Aviation 1810 Samuel Morse Dr Reston VA 22090 Check appropriate boxenclosE payment U NEW SuBSCRIPTION U CHANGE OF ADDRESS Non-AMA subscription rates $1800 12 months US possessions elsewhere including G.nada Mexico $2400 US Schools $900 US Libraries $1350 NAME ADDRESS CITY/STATE __________________________________________________ ZIP MODEL AVIATION 1810 SAMUEL MORSE DR RESTON VA 22090 COMPLETE THIS FORM AND ATTACH MAILING LABEL FROM RECENT IssuE 517 362-6078 sistor shown typical valuefrom half twice value usable optimum value varies motor prop plane speed etc may wish try several val ues singular annoyance about such lowvalue resistors availability especially small physical size high wattage rating needed /2 watt plenty Im still looking convenient source Finally prop stops best used directdrive props speed-reduced props gear belt drive cannot stopped easily Fold ing props much better addition protecting both prop prop shaft folders offer considerable aerodynamic drag reductionjust whats needed high-time gliders Next month Part 7 will deal extensively suitable model designs both prin ciple practice Therell some dis cussion construction techniques model size motor size battery size weight flight timesfor sorts models As closing note having referenced sev eral Radio Shack parts supplies have comment Radio Shack has dis quieting practice suddenly dropping items its catalog Items mentioned herein available writing Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 SAFE FLYING IS NO ACCIDENT COMPLETELY FINISHED R/C AIRCRAFT Completely Finished R/ C Aircraft s & Types Radio Engine Only CG Sky riger--63 trainer $22500 Sig Clip Wing J-3 Cah--54 Spon $25000 SEND FOR COMPLETE LIST HOBBY CAPITOL R/C 46 N Oak St Ventura California 93001 FebrUary 1984 155 sIa & Aaaas Han Gal SHaI-Sdy SILICONE 10 foot coils TUBING ID 062 092 125 us POST $/coiI 235 265 325 54t/COIL LARRY DODGE AERO INC 10210 MANNINGSTILLWATER MN 55082
Edition: Model Aviation - 1984/02
Page Numbers: 58, 59, 60, 61, 62, 151
Half installations topic covered last monthmotor battery radio big items month author looks installation switches connectors fuses wiring etcthe smaller things equally necessary Part 6E Bob Kopski ut - w w YOU MAY WANT review Part 5 go through related some pictures sketches cover mutual areas 1 Switches Generally two common types used electric power systems miniature toggle miniature snap-action switches microswitches Switches used va riety waysmanually servo-driven different things such simple ON OFF operation change speed steps OFF-LO-HI toggle switch easily mounted fuselage external master power con trol toggle may mounted internally actuated through simple servo pushrod arrangement three-position toggle ON-OFF-ON allows OFF-LO HI function Study photos sketches Snap-action switches very useful installations servo-driven func tions Ive using Radio Shack 275-016 lever switch years particularly planes incorporate prop-stop switch very small lightweight can actually doublesticky-foam-taped servo Ive used technique foam tape mounting does tend flow after period time remounting required rigid mounting screws offers advantage re gard Incidentally Radio Shack part has through-holes can carefully tapped 4-40 thread Both Astro Leisure offer heavier-looking microswitch motor control Again illustrations should help scheme never use actuate switch extreme motion control surface servo such elevator Using full up full down move motor switch always seems get flight trouble Having control motor system plane flying near ground downright treacherous also frequently neededan obvious conflict Personally prefer simply install ad ditional channel have fully noninteractive motor control Ive seen trying seemingly simpler technique have abandoned its simple after Switch ratings given voltage current amps sometimes fur ther broken down AC DC practical purposes rating con cern us application current rating Generally life switch given number operations tested specified electrical load before specified degradation occurs minia ture toggles snap-action switches use may rated few amps say three six good job us very rarely fail though com monly control running currents twice motor starting currents several times higher tested operating life use miniature switches would no doubt very poorly compared life rated currentordinary tens hun dreds thousands operations see doesnt really matter too much get tenth switchs usual life thats still operations apt use can feel confident using small switches meet just about common Left assorted small parts described text see glass-barrel fuse holder middle left plastic fuse top oclock position two sizes two-conductor Molex connectors single-conductor crimp-on connectors battery just below plastic fuse Shown three lengths heater-element resistors two kinds toggle switches lever switch toggle switch wires has aluminum tube extension end flattened drilled pushrod Right Fingertip helps us see interchangeable resistor determines LO motor power level Resistor inside fuselage mounted terminal board incooling air flow 58 Model Aviation Above With wing ot Spectra removed looking straight down battery compartment four six cells come view two forwardto rightout sight Air exit holes per pat tern shown last month visible fuselage floor right will goodat spaces between cells Foam blocks take up extra battery compartment area cells can added battery can shifted balance single crimp-on connector set allows adding extra cells have matching connec tions series Wing saddle tape seals off battery air chamber Right Generous cabin area Dan Mittens Taylorcraft permits easy access everything Compare what see what text says Dan could have saved over ounce Note lever switch side servo left battery servos extended arm needs What uncommon need switch Based experience club motor load current somewhere around 14 16 amps begins push bit miniatures described above However such current would also pushing smaller mo tors Bigger better built mo tors such Astro 25 40 cobalts require heftier February 1984 59 Above Hatch removed Spectra reveals lever switch cam wheel collar prop-stop rod switch position can adjusted up down mounting screws slots fuselage side Adjust cam exact timing switching prop-stopping Above Right Miniature toggle switch flat handle pushed pulled servo-actuated pushrod Springs pushrod prevent stall ing servo switch limits John Hickeys Jack Rabbit Right Servo-actuated double pole double throw center off toggle switch provides LO-OFF-HI motor power sequence Dan Gravers Friendly aluminum tube extension carefully epoxied cleaned scored original switch handle tip extension flattened drilled accept clevis case protection against stalling servo servo output CAM OR SERVOARM 0RADIO SHACK 275016 OR SIM NOT USEDNC NO IVJr4Th K9C J B F1 SW] CHARGE JACK REAR VIEW SYSTEM BATTERY POLARIZED CONNECTORS OPTIONAL FUSE OPTIONAL MAIN SWITCH switches Ive successfully used double-pole miniature toggles two switch sections wired parallel control 25 switch rated 5 amps per pole required replacement after about two seasons flying 2 Simple speed controls Motor power can controlled step fashion using servocontrolled three-position toggle switch As shown sketch position toggle puts resistor battery-motor circuit As explained earlier series small drop applied voltage causes substantial power reduction small-value re sistor needed job Such resistor capable carrying motor current may hard find make own simple resistors done using small sections coiled heating element such found older-style electric hot plates able buy replacement nichrome elements hardware store material hard solder use crimp-type terminals resistors As shown microswitch ON lever up option al prop stop retractedI SW2 MICROSWITCH R DAMPING RESISTOR M MOTOR C BRUSH CAPACITOR 001 uF TYPICAL mounted using 4-40 screws blind mount ing nuts plywood former inal board small selection varying length resistors can easily interchanged field achieve desired low-speed per formance sure mount resistor cooling air flow permit touch model structureit will burn 3 Electronic motor controls Electric motors can controlled stop full throttle very smooth fashion using several electronic speed controls pres ently available devices plug receiver output connector just like servo motor control would plug throttle channel Moving throttle stick smoothly varies motor power electronic speed control Ive seen does cause some loss power high end compared motor performance such control percentage basis same motor current power lost fewer-cell batteries batteries having large number cells other words MOTOR ON-OFFDAMPING PROP STOPRADIO SHACK RADIO SHACK271-13C 275-016TAP 4-402 PLACES SWITCH ALUMINUM TUBE TO SERVO N SECURE RED OUTER WELL ADJUST FOLLOWER LOCATION ON ROD SWITCH POSITION ON FUSELAGE SIDE FOR OPTIMUM OPERATION 4-40X1/2 NYLON RE W S FUSELAGE SIDE 1/8 X3/16 SLOTS 2 PLACES MOTOR OFF AS SHOWN\ YELLOW INNER GOLDEN ROD1/16 GOLDEN SULLIVAN 076 RODS WITHROD THREADED ENDS ~~O2O MUSIC WIRE DRILLZ IHAIRPIN MAKE THIS ASSEMBLY WITH HOT STUFF 8 BAKING SODA INNER WIRE ALLOWS SMOOTH BEND STRESS RELIEF WHEN DRILL WHEEL ENGAGING PROP S TAPCOLLAR AS SHOWN PROP STOP IS FORWARD ENGAGED voltage drop controller hurts have low -voltage battery few cells controls least loss seem MOSFETS out put stage type popular among visiting fliers 1983 KRC Electric Fly lost power described above caused part semiconductor switching de vices speed control As result control gets hot again some cooling air over heat-sink plate must Follow manufacturers recommendations stalling device feel good idea have master power switch circuit using electronic motor controls simple toggle switch mounted side fuselage convenient turning motor system power OFF helps assure example some radio glitch wont momentarily activate speed control youre work ing control surface adjustments Ive seen few problems use electronic controls Ill mention Some receivers like being connected motor-battery system connection can cause severe glitching apparent loss range because motor brush noise has easy conductive path receiver some receivers cannot reject kind interference Another problem Ive en countered has apparent up setting overall antenna/counterpoise system receiver simple addition extra stuff connected flight control system adversely affects radio aspects receiver antenna retuning prob ably wont help bit difficult describe easy fix Three rf chokes three controller input leads does trick Chokes about 5 20 microhenries such used various receiver trans mitter circuits good candidates experiences have electronic speed controls other devices electrically connect two systems potential troublemakers well such example may simple elec tronic motor ON-OFF controls with out built-in power regulator re ceiver latter devices permit running radio equipment motor battery designed shut off motor still plenty power left run radio personal preference use separate radio battery accomplish ON-OFF function servo/switch technique described earlier best way avoid problems above use electronic motor controls op ticoupler inputs no hard-wired connection between airborne radio electric power systems though controller plug connected receiver output course problems above common ones believe less likely modem re ceivers Finally no matter what installation consists follow practice physically separating two on-board electrical sys tems Avoid routing receiver wiring espe cially antenna wire near anything 60 Model Aviation TYPICAL ELECTRIC SYSTEM WIRING DIAGRAM power system running motor good noise generator radio static careful tidy installation work will help avoid concern 4 Fuses subject has always interested lot folks KRC Electric Fly Semi nars part primarily interested whether fuse fuse 2 what size 3 what kind As far Im concerned matter mostly personal preference help arrive own choice lets look some considerations purpose fuse electrical system protect costly components equipment inexpensive device used fuse should always located close possible power source just like fuses breakers right power mains residencebefore rest house wiring case fuse should installed wiring close battery Thus thing cant protect against problem battery itself However other problem causes severe high current demand results blown fuse common reasons happening mis-wires shorts either stalled very heavily-loaded motors Thus assuming top-notch wiring job concern would stalled motor have witnessed happen some rea son plane gets snarled some high grass grass tangles stalls prop seconds rising smoke mostly motor brushes windings give up ghost turn crispy critters Eventually insulation system wiring begins melt battery cannot touched because its high temperature Theres lot energy thar cells pardner Generally speaking some form motor ON-OFF control used power can shut off problem observed course theres question like lihood problem occurring first place What comes down pretty much feel about chance youre taking fusing Europeans gen eral seem avoid fuses writers SEAM newsletter argue strongly Personally Ive drifted away use although know sure someday Ill wish fuse What should youre really doubt fuse commonly-used fuse styles pictured Both readily-available auto other stores classic glass tube metal ends type can installed matching fuse holder Radio Shack newer plastic-encased types require slip-on crimp-type wire terminal ends make connection latter parts smaller lighter easier install tuck model As far size goes fuses rated current will blow break con nection popular motors ratings 10 15 amps should quite satisfactory Larger higher-power motors described earlier require higher ratings TYPICAL OFF-LO-HIGH ELECTRIC SYSTEM WIRING DIAGRAM LO OFF HIGH FLATTENED ALUM TUBE I/EPOXY TO SWITCH R 1 M C ARGE JACK REAR VIEW B SYSTEM BATTERY lJ2 POLARIZED CONNECTORS F OPTIONAL FUSE course Some manufacturers provide structions regard Follow Fuses inexpensive can try different ratings youre sure Start lower ratings such 10 amps fuse blows no apparent reason during flight up rating little Unless youre really high-power stuff should no reason go much beyond 20 amps 5 Wiring Some typical system wiring dia grams shown Most electric power sys tems available pre-wired intercon nection harnesses and/or various connectors Its possible cover variation especially available speed controls used general sure follow instructions equipment Some Electric fliers like roll own wiring aspire such undertaking some sugges tions battery packs come pre-wired may want modify assemble own typically use 18-gauge lamp cord zip cord wiring although high-current systems over 12-14 amps long lead lengths warrant heavier wire true wires carrying battery-to-motor current Some other wires such connections separate charge jacks can lighter hook up wire such 20 22 gauge Zip cord always available several colors inexpensive zipped-apart individual wire colors easy convenient keeping track various leads Single-conductor plastic insulated wire also available several sizes colors auto supply stores sure use flexible stranded variety opposed solid-conductor kind cells Ive seen have solder tabs welded cell ends Sometimes may soldered directly together cell cell may used pads wires may easily soldered pays clean straps fine sandpaper SW DOUBLE THROW CENTER OFF SWITCH 3-POSITION R INTERCHANGABLE RESISTER M MOTOR C MOTOR BRUSH CAPACITOR pencil eraser before soldering course always use radio -type solders acid-core types generally solder close cell possible minimize solder strap lengththese arent heavy wire being connected Excess strap length easily cut off Cells massive heat sinks Use sol dering iron both high enough temperature high enough heat capacity allow quick smooth flow solder like tool such Radio Shack 64-2080 handle 64-2082 element 64-2089 tip Avoid use soldering guns vicinity motors extremely strong magnetic field gun transformer may tend de magnetize motor magnets safety battery wiring cells dis charged state Dont soak heat cells Adequate tool heat capacity permits good connection made short-time touch soldering iron careful stripping wire cut strands assure insulation remaining neededsuch wire crosses cell cell Remember case cell negative tenninal around up down cell positive terminal resides small island end Take care cut burn cell outer insulating sleeve may want use smaller soldering tool connections lugs switches connectors Usually solder lugs tight fit 18-gauge larger wire generally tin pre-solder coat both lug stripped wire end lay wire flat against lug reflow solder makes neat adequate joint Sometimes slip some insulating tubing over joint such often done RC connectors Most electric power items made country supplied convenient polar ized cant connect backwards con nectors such made Molex Generally two sizes two-conductor plastic Continued page 62 February 1984 61 revolutionary concept power 1 SV glow plugs model engines used boats cars airplanes NI STARTERITMI uses HeadlockITMI adapter locks onto wont glow plugs start engine Fits Yost pocket comes CIlO charger has LED lights up charging Rechargeable hundreds times gives over hO consecutive starts recharging Available charger Send ad along prepayment receive free shipping handling NI-STARTER$2495 charger Ill OV 220V 12V fast chargerl NI-STARTER$1595 charger Chargers$1295 charger ii 220V orb 2V fast chargeri PLEASE SPECIFY WHICH CHARGER WHEN ORDERINGl 12721 HASKELL LANE BOWIE MARYLAND 207161301464-2260 NEW FOURMOST PRODUCTS FUSELAGE FIXTURE FOURMOST FUSELAGE FIXTURE 5 desrgned ta Astenutieelly align fuselage structures built strings measuring yr eyeballrng Simply slide fear centerine brackets n track ustil alige finrewall tarl vinyl tine bulkheads Clamp fsselagetogetherlightly rubherbands structure wrIl straight track Price 2995 Miter Master Miter Master tour designed usable craftsmae make perfect luiets inn woud accurately sanding pre-setangles squarinafencelAl allowsforprecise9O angles retracts beluw surface Any angle can beset triangular guide using adiacent side cumplemeet ut angle will formed making invaluable fur truss cunstractiun yew cyanuacrylare adhesives require accurately fitted ivints te achieve full strength Minter Master will enable te make naurly FOURMOST PRODUCTS 4040 24th Ave Forest Grove OR 97116 Price $950 Asnentufee bound 503 357-2732 mates have used shown among pictures recently smaller two has become popular connectors available Astro Leisure electron tcs supply houses Another connector style may find use ful single-conductor crimp-on type also pictured require crimping tool proper installation Often 1 wish con nect single wires kind connector connecting plastic fuses mentioned earlier single connectors available already insulated can obtained Radio Shack auto stores hardware stores sure pur chase size suitable 18 16-gauge wire few things should know about both connector types mating fit very tight new often very hard pull needed separate Frequently suddenly let go hands can easily disassemble model wary other hand same con nectors can become quite loose after re peated use happens con nection quality becomes doubtful Fortunately theyre low cost easy replace way some polarized Molex connectors have snap indents purpose being sure stay together catches necessary trim off modeling knife Another connector commonly used purposes mentioned Part 4the charge plug jack parts made Switchcraft available As tro have used years extremely reliable convenient Proper connection polarity shown drawings very helpful con venient flying field fliers use similar charging connectors sometimes neces sary share charging equipment Switchcraft parts common use KRC Now some wiring trivia single 10-in-long conductor 18-gauge lamp cord carrying 10 amperes has voltage drop 0054 volts power dissipation loss 054 watts 20 amps dissipation increases 216 watts wire will probably get warm Use heavier wire case same 10-in-length wire weighs about 013 oz next time somebody flight line acts like knows everything can lay him keep em mind too 6 Prop stops have using prop stops years thanks idea presented Jim Zarehibski Pioneer 15 glider RCM long ago idea prop stop simply locate unpowered prop hQrizontal position landing can fuselage skid prop tip offers distinct advantage fewer broken props importantly fewer bent armature shafts Clearly prop stop almost required model no land ing gear practice prop stop actu Continued page 155 62 Model Aviation 7 N I-STARTER MFG OF NI-STARTER $2495 charger h NEW R/C BOOKLET Answers questions often asked want get started RIG flying PLUS troduces best airplane start GOLDEN FALCON receive copy SEND $200 TO ST CROIX OF PARK FALLS LTD PO Box 279P Park Falls WI 54552 ation standard 22 gauge stranded hook-up wire will adequate Before actually start wiring might want note wiring sketch shows switches appear bottom view next column will have information use resistor shown control box wiring controlling servos speed wire servos some sugges tions insulate control lines flight control handle planes bellcrank system Send items CL Scale Bill Boss 77-06 269th St New Hyde Park NY 11040 Electrics/Kopski "" ~ oaoe 62 ated same servo operates ON OFF switch Refer sketch pictures Parts 2 suggested installation can have vari ations example instead switch being actuated follower prop stop rod switch can directly mounted servo described earlier Also may find some suitable alternative stop-rod material use case sure adjust lengths throws timing prop stop clear prop bet bre switch turns ON switch turns OFF before stop advances prop necessary have small repeatable drag part prop bladethe Great Lakes Model Company PO Box 308 Tawas City Ml 48763 AT-6 SNJ HARVARD Wingspan 63 375 60 Engine 7 lbs Complete List Price $28500 Factory Direct $22800 Michigan residents add 4% salns taa Send SASE fnr Brochare Dealer Inquiries Welcome stop rod does have thrust completely through prop thickness Small motors have three armature poles tend cog ie stop three specific armature positions due pull magnets Mount prop adapter prop stop engages close natural armature resting positions Motors three poles have less tendency cog excep tion some very strong cobalt mag nets prop will tend spin freely case just ease stop prop Sometimes takes little practice adjustment get prop stop repeatedly desired horizontal position persist resistor shown sketch serves purpose braking motor switch goes OFF state resistor instead power switched across stillcoasting motor Without damping re sistor motor prop likely con tinue spinning prop stop withstanding Such coasting armature/prop has con siderable inertiareadily appreciated should engage finger can easily chew up stop rod freewheeling motor its windmill blades acts generator actually develop ing voltage its open terminals resistor forms electrical loada dynamic brakeand limits resulting current surge slow ing stopping generator re LET US KNOW WHERE YOU ARE GOING move please let us know advancesix weeks required change address Attach current MA mailing label check appropriate box mail Subscrip tion Dept Model Aviation 1810 Samuel Morse Dr Reston VA 22090 Check appropriate boxenclosE payment U NEW SuBSCRIPTION U CHANGE OF ADDRESS Non-AMA subscription rates $1800 12 months US possessions elsewhere including G.nada Mexico $2400 US Schools $900 US Libraries $1350 NAME ADDRESS CITY/STATE __________________________________________________ ZIP MODEL AVIATION 1810 SAMUEL MORSE DR RESTON VA 22090 COMPLETE THIS FORM AND ATTACH MAILING LABEL FROM RECENT IssuE 517 362-6078 sistor shown typical valuefrom half twice value usable optimum value varies motor prop plane speed etc may wish try several val ues singular annoyance about such lowvalue resistors availability especially small physical size high wattage rating needed /2 watt plenty Im still looking convenient source Finally prop stops best used directdrive props speed-reduced props gear belt drive cannot stopped easily Fold ing props much better addition protecting both prop prop shaft folders offer considerable aerodynamic drag reductionjust whats needed high-time gliders Next month Part 7 will deal extensively suitable model designs both prin ciple practice Therell some dis cussion construction techniques model size motor size battery size weight flight timesfor sorts models As closing note having referenced sev eral Radio Shack parts supplies have comment Radio Shack has dis quieting practice suddenly dropping items its catalog Items mentioned herein available writing Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 SAFE FLYING IS NO ACCIDENT COMPLETELY FINISHED R/C AIRCRAFT Completely Finished R/ C Aircraft s & Types Radio Engine Only CG Sky riger--63 trainer $22500 Sig Clip Wing J-3 Cah--54 Spon $25000 SEND FOR COMPLETE LIST HOBBY CAPITOL R/C 46 N Oak St Ventura California 93001 FebrUary 1984 155 sIa & Aaaas Han Gal SHaI-Sdy SILICONE 10 foot coils TUBING ID 062 092 125 us POST $/coiI 235 265 325 54t/COIL LARRY DODGE AERO INC 10210 MANNINGSTILLWATER MN 55082
Edition: Model Aviation - 1984/02
Page Numbers: 58, 59, 60, 61, 62, 151
Half installations topic covered last monthmotor battery radio big items month author looks installation switches connectors fuses wiring etcthe smaller things equally necessary Part 6E Bob Kopski ut - w w YOU MAY WANT review Part 5 go through related some pictures sketches cover mutual areas 1 Switches Generally two common types used electric power systems miniature toggle miniature snap-action switches microswitches Switches used va riety waysmanually servo-driven different things such simple ON OFF operation change speed steps OFF-LO-HI toggle switch easily mounted fuselage external master power con trol toggle may mounted internally actuated through simple servo pushrod arrangement three-position toggle ON-OFF-ON allows OFF-LO HI function Study photos sketches Snap-action switches very useful installations servo-driven func tions Ive using Radio Shack 275-016 lever switch years particularly planes incorporate prop-stop switch very small lightweight can actually doublesticky-foam-taped servo Ive used technique foam tape mounting does tend flow after period time remounting required rigid mounting screws offers advantage re gard Incidentally Radio Shack part has through-holes can carefully tapped 4-40 thread Both Astro Leisure offer heavier-looking microswitch motor control Again illustrations should help scheme never use actuate switch extreme motion control surface servo such elevator Using full up full down move motor switch always seems get flight trouble Having control motor system plane flying near ground downright treacherous also frequently neededan obvious conflict Personally prefer simply install ad ditional channel have fully noninteractive motor control Ive seen trying seemingly simpler technique have abandoned its simple after Switch ratings given voltage current amps sometimes fur ther broken down AC DC practical purposes rating con cern us application current rating Generally life switch given number operations tested specified electrical load before specified degradation occurs minia ture toggles snap-action switches use may rated few amps say three six good job us very rarely fail though com monly control running currents twice motor starting currents several times higher tested operating life use miniature switches would no doubt very poorly compared life rated currentordinary tens hun dreds thousands operations see doesnt really matter too much get tenth switchs usual life thats still operations apt use can feel confident using small switches meet just about common Left assorted small parts described text see glass-barrel fuse holder middle left plastic fuse top oclock position two sizes two-conductor Molex connectors single-conductor crimp-on connectors battery just below plastic fuse Shown three lengths heater-element resistors two kinds toggle switches lever switch toggle switch wires has aluminum tube extension end flattened drilled pushrod Right Fingertip helps us see interchangeable resistor determines LO motor power level Resistor inside fuselage mounted terminal board incooling air flow 58 Model Aviation Above With wing ot Spectra removed looking straight down battery compartment four six cells come view two forwardto rightout sight Air exit holes per pat tern shown last month visible fuselage floor right will goodat spaces between cells Foam blocks take up extra battery compartment area cells can added battery can shifted balance single crimp-on connector set allows adding extra cells have matching connec tions series Wing saddle tape seals off battery air chamber Right Generous cabin area Dan Mittens Taylorcraft permits easy access everything Compare what see what text says Dan could have saved over ounce Note lever switch side servo left battery servos extended arm needs What uncommon need switch Based experience club motor load current somewhere around 14 16 amps begins push bit miniatures described above However such current would also pushing smaller mo tors Bigger better built mo tors such Astro 25 40 cobalts require heftier February 1984 59 Above Hatch removed Spectra reveals lever switch cam wheel collar prop-stop rod switch position can adjusted up down mounting screws slots fuselage side Adjust cam exact timing switching prop-stopping Above Right Miniature toggle switch flat handle pushed pulled servo-actuated pushrod Springs pushrod prevent stall ing servo switch limits John Hickeys Jack Rabbit Right Servo-actuated double pole double throw center off toggle switch provides LO-OFF-HI motor power sequence Dan Gravers Friendly aluminum tube extension carefully epoxied cleaned scored original switch handle tip extension flattened drilled accept clevis case protection against stalling servo servo output CAM OR SERVOARM 0RADIO SHACK 275016 OR SIM NOT USEDNC NO IVJr4Th K9C J B F1 SW] CHARGE JACK REAR VIEW SYSTEM BATTERY POLARIZED CONNECTORS OPTIONAL FUSE OPTIONAL MAIN SWITCH switches Ive successfully used double-pole miniature toggles two switch sections wired parallel control 25 switch rated 5 amps per pole required replacement after about two seasons flying 2 Simple speed controls Motor power can controlled step fashion using servocontrolled three-position toggle switch As shown sketch position toggle puts resistor battery-motor circuit As explained earlier series small drop applied voltage causes substantial power reduction small-value re sistor needed job Such resistor capable carrying motor current may hard find make own simple resistors done using small sections coiled heating element such found older-style electric hot plates able buy replacement nichrome elements hardware store material hard solder use crimp-type terminals resistors As shown microswitch ON lever up option al prop stop retractedI SW2 MICROSWITCH R DAMPING RESISTOR M MOTOR C BRUSH CAPACITOR 001 uF TYPICAL mounted using 4-40 screws blind mount ing nuts plywood former inal board small selection varying length resistors can easily interchanged field achieve desired low-speed per formance sure mount resistor cooling air flow permit touch model structureit will burn 3 Electronic motor controls Electric motors can controlled stop full throttle very smooth fashion using several electronic speed controls pres ently available devices plug receiver output connector just like servo motor control would plug throttle channel Moving throttle stick smoothly varies motor power electronic speed control Ive seen does cause some loss power high end compared motor performance such control percentage basis same motor current power lost fewer-cell batteries batteries having large number cells other words MOTOR ON-OFFDAMPING PROP STOPRADIO SHACK RADIO SHACK271-13C 275-016TAP 4-402 PLACES SWITCH ALUMINUM TUBE TO SERVO N SECURE RED OUTER WELL ADJUST FOLLOWER LOCATION ON ROD SWITCH POSITION ON FUSELAGE SIDE FOR OPTIMUM OPERATION 4-40X1/2 NYLON RE W S FUSELAGE SIDE 1/8 X3/16 SLOTS 2 PLACES MOTOR OFF AS SHOWN\ YELLOW INNER GOLDEN ROD1/16 GOLDEN SULLIVAN 076 RODS WITHROD THREADED ENDS ~~O2O MUSIC WIRE DRILLZ IHAIRPIN MAKE THIS ASSEMBLY WITH HOT STUFF 8 BAKING SODA INNER WIRE ALLOWS SMOOTH BEND STRESS RELIEF WHEN DRILL WHEEL ENGAGING PROP S TAPCOLLAR AS SHOWN PROP STOP IS FORWARD ENGAGED voltage drop controller hurts have low -voltage battery few cells controls least loss seem MOSFETS out put stage type popular among visiting fliers 1983 KRC Electric Fly lost power described above caused part semiconductor switching de vices speed control As result control gets hot again some cooling air over heat-sink plate must Follow manufacturers recommendations stalling device feel good idea have master power switch circuit using electronic motor controls simple toggle switch mounted side fuselage convenient turning motor system power OFF helps assure example some radio glitch wont momentarily activate speed control youre work ing control surface adjustments Ive seen few problems use electronic controls Ill mention Some receivers like being connected motor-battery system connection can cause severe glitching apparent loss range because motor brush noise has easy conductive path receiver some receivers cannot reject kind interference Another problem Ive en countered has apparent up setting overall antenna/counterpoise system receiver simple addition extra stuff connected flight control system adversely affects radio aspects receiver antenna retuning prob ably wont help bit difficult describe easy fix Three rf chokes three controller input leads does trick Chokes about 5 20 microhenries such used various receiver trans mitter circuits good candidates experiences have electronic speed controls other devices electrically connect two systems potential troublemakers well such example may simple elec tronic motor ON-OFF controls with out built-in power regulator re ceiver latter devices permit running radio equipment motor battery designed shut off motor still plenty power left run radio personal preference use separate radio battery accomplish ON-OFF function servo/switch technique described earlier best way avoid problems above use electronic motor controls op ticoupler inputs no hard-wired connection between airborne radio electric power systems though controller plug connected receiver output course problems above common ones believe less likely modem re ceivers Finally no matter what installation consists follow practice physically separating two on-board electrical sys tems Avoid routing receiver wiring espe cially antenna wire near anything 60 Model Aviation TYPICAL ELECTRIC SYSTEM WIRING DIAGRAM power system running motor good noise generator radio static careful tidy installation work will help avoid concern 4 Fuses subject has always interested lot folks KRC Electric Fly Semi nars part primarily interested whether fuse fuse 2 what size 3 what kind As far Im concerned matter mostly personal preference help arrive own choice lets look some considerations purpose fuse electrical system protect costly components equipment inexpensive device used fuse should always located close possible power source just like fuses breakers right power mains residencebefore rest house wiring case fuse should installed wiring close battery Thus thing cant protect against problem battery itself However other problem causes severe high current demand results blown fuse common reasons happening mis-wires shorts either stalled very heavily-loaded motors Thus assuming top-notch wiring job concern would stalled motor have witnessed happen some rea son plane gets snarled some high grass grass tangles stalls prop seconds rising smoke mostly motor brushes windings give up ghost turn crispy critters Eventually insulation system wiring begins melt battery cannot touched because its high temperature Theres lot energy thar cells pardner Generally speaking some form motor ON-OFF control used power can shut off problem observed course theres question like lihood problem occurring first place What comes down pretty much feel about chance youre taking fusing Europeans gen eral seem avoid fuses writers SEAM newsletter argue strongly Personally Ive drifted away use although know sure someday Ill wish fuse What should youre really doubt fuse commonly-used fuse styles pictured Both readily-available auto other stores classic glass tube metal ends type can installed matching fuse holder Radio Shack newer plastic-encased types require slip-on crimp-type wire terminal ends make connection latter parts smaller lighter easier install tuck model As far size goes fuses rated current will blow break con nection popular motors ratings 10 15 amps should quite satisfactory Larger higher-power motors described earlier require higher ratings TYPICAL OFF-LO-HIGH ELECTRIC SYSTEM WIRING DIAGRAM LO OFF HIGH FLATTENED ALUM TUBE I/EPOXY TO SWITCH R 1 M C ARGE JACK REAR VIEW B SYSTEM BATTERY lJ2 POLARIZED CONNECTORS F OPTIONAL FUSE course Some manufacturers provide structions regard Follow Fuses inexpensive can try different ratings youre sure Start lower ratings such 10 amps fuse blows no apparent reason during flight up rating little Unless youre really high-power stuff should no reason go much beyond 20 amps 5 Wiring Some typical system wiring dia grams shown Most electric power sys tems available pre-wired intercon nection harnesses and/or various connectors Its possible cover variation especially available speed controls used general sure follow instructions equipment Some Electric fliers like roll own wiring aspire such undertaking some sugges tions battery packs come pre-wired may want modify assemble own typically use 18-gauge lamp cord zip cord wiring although high-current systems over 12-14 amps long lead lengths warrant heavier wire true wires carrying battery-to-motor current Some other wires such connections separate charge jacks can lighter hook up wire such 20 22 gauge Zip cord always available several colors inexpensive zipped-apart individual wire colors easy convenient keeping track various leads Single-conductor plastic insulated wire also available several sizes colors auto supply stores sure use flexible stranded variety opposed solid-conductor kind cells Ive seen have solder tabs welded cell ends Sometimes may soldered directly together cell cell may used pads wires may easily soldered pays clean straps fine sandpaper SW DOUBLE THROW CENTER OFF SWITCH 3-POSITION R INTERCHANGABLE RESISTER M MOTOR C MOTOR BRUSH CAPACITOR pencil eraser before soldering course always use radio -type solders acid-core types generally solder close cell possible minimize solder strap lengththese arent heavy wire being connected Excess strap length easily cut off Cells massive heat sinks Use sol dering iron both high enough temperature high enough heat capacity allow quick smooth flow solder like tool such Radio Shack 64-2080 handle 64-2082 element 64-2089 tip Avoid use soldering guns vicinity motors extremely strong magnetic field gun transformer may tend de magnetize motor magnets safety battery wiring cells dis charged state Dont soak heat cells Adequate tool heat capacity permits good connection made short-time touch soldering iron careful stripping wire cut strands assure insulation remaining neededsuch wire crosses cell cell Remember case cell negative tenninal around up down cell positive terminal resides small island end Take care cut burn cell outer insulating sleeve may want use smaller soldering tool connections lugs switches connectors Usually solder lugs tight fit 18-gauge larger wire generally tin pre-solder coat both lug stripped wire end lay wire flat against lug reflow solder makes neat adequate joint Sometimes slip some insulating tubing over joint such often done RC connectors Most electric power items made country supplied convenient polar ized cant connect backwards con nectors such made Molex Generally two sizes two-conductor plastic Continued page 62 February 1984 61 revolutionary concept power 1 SV glow plugs model engines used boats cars airplanes NI STARTERITMI uses HeadlockITMI adapter locks onto wont glow plugs start engine Fits Yost pocket comes CIlO charger has LED lights up charging Rechargeable hundreds times gives over hO consecutive starts recharging Available charger Send ad along prepayment receive free shipping handling NI-STARTER$2495 charger Ill OV 220V 12V fast chargerl NI-STARTER$1595 charger Chargers$1295 charger ii 220V orb 2V fast chargeri PLEASE SPECIFY WHICH CHARGER WHEN ORDERINGl 12721 HASKELL LANE BOWIE MARYLAND 207161301464-2260 NEW FOURMOST PRODUCTS FUSELAGE FIXTURE FOURMOST FUSELAGE FIXTURE 5 desrgned ta Astenutieelly align fuselage structures built strings measuring yr eyeballrng Simply slide fear centerine brackets n track ustil alige finrewall tarl vinyl tine bulkheads Clamp fsselagetogetherlightly rubherbands structure wrIl straight track Price 2995 Miter Master Miter Master tour designed usable craftsmae make perfect luiets inn woud accurately sanding pre-setangles squarinafencelAl allowsforprecise9O angles retracts beluw surface Any angle can beset triangular guide using adiacent side cumplemeet ut angle will formed making invaluable fur truss cunstractiun yew cyanuacrylare adhesives require accurately fitted ivints te achieve full strength Minter Master will enable te make naurly FOURMOST PRODUCTS 4040 24th Ave Forest Grove OR 97116 Price $950 Asnentufee bound 503 357-2732 mates have used shown among pictures recently smaller two has become popular connectors available Astro Leisure electron tcs supply houses Another connector style may find use ful single-conductor crimp-on type also pictured require crimping tool proper installation Often 1 wish con nect single wires kind connector connecting plastic fuses mentioned earlier single connectors available already insulated can obtained Radio Shack auto stores hardware stores sure pur chase size suitable 18 16-gauge wire few things should know about both connector types mating fit very tight new often very hard pull needed separate Frequently suddenly let go hands can easily disassemble model wary other hand same con nectors can become quite loose after re peated use happens con nection quality becomes doubtful Fortunately theyre low cost easy replace way some polarized Molex connectors have snap indents purpose being sure stay together catches necessary trim off modeling knife Another connector commonly used purposes mentioned Part 4the charge plug jack parts made Switchcraft available As tro have used years extremely reliable convenient Proper connection polarity shown drawings very helpful con venient flying field fliers use similar charging connectors sometimes neces sary share charging equipment Switchcraft parts common use KRC Now some wiring trivia single 10-in-long conductor 18-gauge lamp cord carrying 10 amperes has voltage drop 0054 volts power dissipation loss 054 watts 20 amps dissipation increases 216 watts wire will probably get warm Use heavier wire case same 10-in-length wire weighs about 013 oz next time somebody flight line acts like knows everything can lay him keep em mind too 6 Prop stops have using prop stops years thanks idea presented Jim Zarehibski Pioneer 15 glider RCM long ago idea prop stop simply locate unpowered prop hQrizontal position landing can fuselage skid prop tip offers distinct advantage fewer broken props importantly fewer bent armature shafts Clearly prop stop almost required model no land ing gear practice prop stop actu Continued page 155 62 Model Aviation 7 N I-STARTER MFG OF NI-STARTER $2495 charger h NEW R/C BOOKLET Answers questions often asked want get started RIG flying PLUS troduces best airplane start GOLDEN FALCON receive copy SEND $200 TO ST CROIX OF PARK FALLS LTD PO Box 279P Park Falls WI 54552 ation standard 22 gauge stranded hook-up wire will adequate Before actually start wiring might want note wiring sketch shows switches appear bottom view next column will have information use resistor shown control box wiring controlling servos speed wire servos some sugges tions insulate control lines flight control handle planes bellcrank system Send items CL Scale Bill Boss 77-06 269th St New Hyde Park NY 11040 Electrics/Kopski "" ~ oaoe 62 ated same servo operates ON OFF switch Refer sketch pictures Parts 2 suggested installation can have vari ations example instead switch being actuated follower prop stop rod switch can directly mounted servo described earlier Also may find some suitable alternative stop-rod material use case sure adjust lengths throws timing prop stop clear prop bet bre switch turns ON switch turns OFF before stop advances prop necessary have small repeatable drag part prop bladethe Great Lakes Model Company PO Box 308 Tawas City Ml 48763 AT-6 SNJ HARVARD Wingspan 63 375 60 Engine 7 lbs Complete List Price $28500 Factory Direct $22800 Michigan residents add 4% salns taa Send SASE fnr Brochare Dealer Inquiries Welcome stop rod does have thrust completely through prop thickness Small motors have three armature poles tend cog ie stop three specific armature positions due pull magnets Mount prop adapter prop stop engages close natural armature resting positions Motors three poles have less tendency cog excep tion some very strong cobalt mag nets prop will tend spin freely case just ease stop prop Sometimes takes little practice adjustment get prop stop repeatedly desired horizontal position persist resistor shown sketch serves purpose braking motor switch goes OFF state resistor instead power switched across stillcoasting motor Without damping re sistor motor prop likely con tinue spinning prop stop withstanding Such coasting armature/prop has con siderable inertiareadily appreciated should engage finger can easily chew up stop rod freewheeling motor its windmill blades acts generator actually develop ing voltage its open terminals resistor forms electrical loada dynamic brakeand limits resulting current surge slow ing stopping generator re LET US KNOW WHERE YOU ARE GOING move please let us know advancesix weeks required change address Attach current MA mailing label check appropriate box mail Subscrip tion Dept Model Aviation 1810 Samuel Morse Dr Reston VA 22090 Check appropriate boxenclosE payment U NEW SuBSCRIPTION U CHANGE OF ADDRESS Non-AMA subscription rates $1800 12 months US possessions elsewhere including G.nada Mexico $2400 US Schools $900 US Libraries $1350 NAME ADDRESS CITY/STATE __________________________________________________ ZIP MODEL AVIATION 1810 SAMUEL MORSE DR RESTON VA 22090 COMPLETE THIS FORM AND ATTACH MAILING LABEL FROM RECENT IssuE 517 362-6078 sistor shown typical valuefrom half twice value usable optimum value varies motor prop plane speed etc may wish try several val ues singular annoyance about such lowvalue resistors availability especially small physical size high wattage rating needed /2 watt plenty Im still looking convenient source Finally prop stops best used directdrive props speed-reduced props gear belt drive cannot stopped easily Fold ing props much better addition protecting both prop prop shaft folders offer considerable aerodynamic drag reductionjust whats needed high-time gliders Next month Part 7 will deal extensively suitable model designs both prin ciple practice Therell some dis cussion construction techniques model size motor size battery size weight flight timesfor sorts models As closing note having referenced sev eral Radio Shack parts supplies have comment Radio Shack has dis quieting practice suddenly dropping items its catalog Items mentioned herein available writing Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 SAFE FLYING IS NO ACCIDENT COMPLETELY FINISHED R/C AIRCRAFT Completely Finished R/ C Aircraft s & Types Radio Engine Only CG Sky riger--63 trainer $22500 Sig Clip Wing J-3 Cah--54 Spon $25000 SEND FOR COMPLETE LIST HOBBY CAPITOL R/C 46 N Oak St Ventura California 93001 FebrUary 1984 155 sIa & Aaaas Han Gal SHaI-Sdy SILICONE 10 foot coils TUBING ID 062 092 125 us POST $/coiI 235 265 325 54t/COIL LARRY DODGE AERO INC 10210 MANNINGSTILLWATER MN 55082
Edition: Model Aviation - 1984/02
Page Numbers: 58, 59, 60, 61, 62, 151
Half installations topic covered last monthmotor battery radio big items month author looks installation switches connectors fuses wiring etcthe smaller things equally necessary Part 6E Bob Kopski ut - w w YOU MAY WANT review Part 5 go through related some pictures sketches cover mutual areas 1 Switches Generally two common types used electric power systems miniature toggle miniature snap-action switches microswitches Switches used va riety waysmanually servo-driven different things such simple ON OFF operation change speed steps OFF-LO-HI toggle switch easily mounted fuselage external master power con trol toggle may mounted internally actuated through simple servo pushrod arrangement three-position toggle ON-OFF-ON allows OFF-LO HI function Study photos sketches Snap-action switches very useful installations servo-driven func tions Ive using Radio Shack 275-016 lever switch years particularly planes incorporate prop-stop switch very small lightweight can actually doublesticky-foam-taped servo Ive used technique foam tape mounting does tend flow after period time remounting required rigid mounting screws offers advantage re gard Incidentally Radio Shack part has through-holes can carefully tapped 4-40 thread Both Astro Leisure offer heavier-looking microswitch motor control Again illustrations should help scheme never use actuate switch extreme motion control surface servo such elevator Using full up full down move motor switch always seems get flight trouble Having control motor system plane flying near ground downright treacherous also frequently neededan obvious conflict Personally prefer simply install ad ditional channel have fully noninteractive motor control Ive seen trying seemingly simpler technique have abandoned its simple after Switch ratings given voltage current amps sometimes fur ther broken down AC DC practical purposes rating con cern us application current rating Generally life switch given number operations tested specified electrical load before specified degradation occurs minia ture toggles snap-action switches use may rated few amps say three six good job us very rarely fail though com monly control running currents twice motor starting currents several times higher tested operating life use miniature switches would no doubt very poorly compared life rated currentordinary tens hun dreds thousands operations see doesnt really matter too much get tenth switchs usual life thats still operations apt use can feel confident using small switches meet just about common Left assorted small parts described text see glass-barrel fuse holder middle left plastic fuse top oclock position two sizes two-conductor Molex connectors single-conductor crimp-on connectors battery just below plastic fuse Shown three lengths heater-element resistors two kinds toggle switches lever switch toggle switch wires has aluminum tube extension end flattened drilled pushrod Right Fingertip helps us see interchangeable resistor determines LO motor power level Resistor inside fuselage mounted terminal board incooling air flow 58 Model Aviation Above With wing ot Spectra removed looking straight down battery compartment four six cells come view two forwardto rightout sight Air exit holes per pat tern shown last month visible fuselage floor right will goodat spaces between cells Foam blocks take up extra battery compartment area cells can added battery can shifted balance single crimp-on connector set allows adding extra cells have matching connec tions series Wing saddle tape seals off battery air chamber Right Generous cabin area Dan Mittens Taylorcraft permits easy access everything Compare what see what text says Dan could have saved over ounce Note lever switch side servo left battery servos extended arm needs What uncommon need switch Based experience club motor load current somewhere around 14 16 amps begins push bit miniatures described above However such current would also pushing smaller mo tors Bigger better built mo tors such Astro 25 40 cobalts require heftier February 1984 59 Above Hatch removed Spectra reveals lever switch cam wheel collar prop-stop rod switch position can adjusted up down mounting screws slots fuselage side Adjust cam exact timing switching prop-stopping Above Right Miniature toggle switch flat handle pushed pulled servo-actuated pushrod Springs pushrod prevent stall ing servo switch limits John Hickeys Jack Rabbit Right Servo-actuated double pole double throw center off toggle switch provides LO-OFF-HI motor power sequence Dan Gravers Friendly aluminum tube extension carefully epoxied cleaned scored original switch handle tip extension flattened drilled accept clevis case protection against stalling servo servo output CAM OR SERVOARM 0RADIO SHACK 275016 OR SIM NOT USEDNC NO IVJr4Th K9C J B F1 SW] CHARGE JACK REAR VIEW SYSTEM BATTERY POLARIZED CONNECTORS OPTIONAL FUSE OPTIONAL MAIN SWITCH switches Ive successfully used double-pole miniature toggles two switch sections wired parallel control 25 switch rated 5 amps per pole required replacement after about two seasons flying 2 Simple speed controls Motor power can controlled step fashion using servocontrolled three-position toggle switch As shown sketch position toggle puts resistor battery-motor circuit As explained earlier series small drop applied voltage causes substantial power reduction small-value re sistor needed job Such resistor capable carrying motor current may hard find make own simple resistors done using small sections coiled heating element such found older-style electric hot plates able buy replacement nichrome elements hardware store material hard solder use crimp-type terminals resistors As shown microswitch ON lever up option al prop stop retractedI SW2 MICROSWITCH R DAMPING RESISTOR M MOTOR C BRUSH CAPACITOR 001 uF TYPICAL mounted using 4-40 screws blind mount ing nuts plywood former inal board small selection varying length resistors can easily interchanged field achieve desired low-speed per formance sure mount resistor cooling air flow permit touch model structureit will burn 3 Electronic motor controls Electric motors can controlled stop full throttle very smooth fashion using several electronic speed controls pres ently available devices plug receiver output connector just like servo motor control would plug throttle channel Moving throttle stick smoothly varies motor power electronic speed control Ive seen does cause some loss power high end compared motor performance such control percentage basis same motor current power lost fewer-cell batteries batteries having large number cells other words MOTOR ON-OFFDAMPING PROP STOPRADIO SHACK RADIO SHACK271-13C 275-016TAP 4-402 PLACES SWITCH ALUMINUM TUBE TO SERVO N SECURE RED OUTER WELL ADJUST FOLLOWER LOCATION ON ROD SWITCH POSITION ON FUSELAGE SIDE FOR OPTIMUM OPERATION 4-40X1/2 NYLON RE W S FUSELAGE SIDE 1/8 X3/16 SLOTS 2 PLACES MOTOR OFF AS SHOWN\ YELLOW INNER GOLDEN ROD1/16 GOLDEN SULLIVAN 076 RODS WITHROD THREADED ENDS ~~O2O MUSIC WIRE DRILLZ IHAIRPIN MAKE THIS ASSEMBLY WITH HOT STUFF 8 BAKING SODA INNER WIRE ALLOWS SMOOTH BEND STRESS RELIEF WHEN DRILL WHEEL ENGAGING PROP S TAPCOLLAR AS SHOWN PROP STOP IS FORWARD ENGAGED voltage drop controller hurts have low -voltage battery few cells controls least loss seem MOSFETS out put stage type popular among visiting fliers 1983 KRC Electric Fly lost power described above caused part semiconductor switching de vices speed control As result control gets hot again some cooling air over heat-sink plate must Follow manufacturers recommendations stalling device feel good idea have master power switch circuit using electronic motor controls simple toggle switch mounted side fuselage convenient turning motor system power OFF helps assure example some radio glitch wont momentarily activate speed control youre work ing control surface adjustments Ive seen few problems use electronic controls Ill mention Some receivers like being connected motor-battery system connection can cause severe glitching apparent loss range because motor brush noise has easy conductive path receiver some receivers cannot reject kind interference Another problem Ive en countered has apparent up setting overall antenna/counterpoise system receiver simple addition extra stuff connected flight control system adversely affects radio aspects receiver antenna retuning prob ably wont help bit difficult describe easy fix Three rf chokes three controller input leads does trick Chokes about 5 20 microhenries such used various receiver trans mitter circuits good candidates experiences have electronic speed controls other devices electrically connect two systems potential troublemakers well such example may simple elec tronic motor ON-OFF controls with out built-in power regulator re ceiver latter devices permit running radio equipment motor battery designed shut off motor still plenty power left run radio personal preference use separate radio battery accomplish ON-OFF function servo/switch technique described earlier best way avoid problems above use electronic motor controls op ticoupler inputs no hard-wired connection between airborne radio electric power systems though controller plug connected receiver output course problems above common ones believe less likely modem re ceivers Finally no matter what installation consists follow practice physically separating two on-board electrical sys tems Avoid routing receiver wiring espe cially antenna wire near anything 60 Model Aviation TYPICAL ELECTRIC SYSTEM WIRING DIAGRAM power system running motor good noise generator radio static careful tidy installation work will help avoid concern 4 Fuses subject has always interested lot folks KRC Electric Fly Semi nars part primarily interested whether fuse fuse 2 what size 3 what kind As far Im concerned matter mostly personal preference help arrive own choice lets look some considerations purpose fuse electrical system protect costly components equipment inexpensive device used fuse should always located close possible power source just like fuses breakers right power mains residencebefore rest house wiring case fuse should installed wiring close battery Thus thing cant protect against problem battery itself However other problem causes severe high current demand results blown fuse common reasons happening mis-wires shorts either stalled very heavily-loaded motors Thus assuming top-notch wiring job concern would stalled motor have witnessed happen some rea son plane gets snarled some high grass grass tangles stalls prop seconds rising smoke mostly motor brushes windings give up ghost turn crispy critters Eventually insulation system wiring begins melt battery cannot touched because its high temperature Theres lot energy thar cells pardner Generally speaking some form motor ON-OFF control used power can shut off problem observed course theres question like lihood problem occurring first place What comes down pretty much feel about chance youre taking fusing Europeans gen eral seem avoid fuses writers SEAM newsletter argue strongly Personally Ive drifted away use although know sure someday Ill wish fuse What should youre really doubt fuse commonly-used fuse styles pictured Both readily-available auto other stores classic glass tube metal ends type can installed matching fuse holder Radio Shack newer plastic-encased types require slip-on crimp-type wire terminal ends make connection latter parts smaller lighter easier install tuck model As far size goes fuses rated current will blow break con nection popular motors ratings 10 15 amps should quite satisfactory Larger higher-power motors described earlier require higher ratings TYPICAL OFF-LO-HIGH ELECTRIC SYSTEM WIRING DIAGRAM LO OFF HIGH FLATTENED ALUM TUBE I/EPOXY TO SWITCH R 1 M C ARGE JACK REAR VIEW B SYSTEM BATTERY lJ2 POLARIZED CONNECTORS F OPTIONAL FUSE course Some manufacturers provide structions regard Follow Fuses inexpensive can try different ratings youre sure Start lower ratings such 10 amps fuse blows no apparent reason during flight up rating little Unless youre really high-power stuff should no reason go much beyond 20 amps 5 Wiring Some typical system wiring dia grams shown Most electric power sys tems available pre-wired intercon nection harnesses and/or various connectors Its possible cover variation especially available speed controls used general sure follow instructions equipment Some Electric fliers like roll own wiring aspire such undertaking some sugges tions battery packs come pre-wired may want modify assemble own typically use 18-gauge lamp cord zip cord wiring although high-current systems over 12-14 amps long lead lengths warrant heavier wire true wires carrying battery-to-motor current Some other wires such connections separate charge jacks can lighter hook up wire such 20 22 gauge Zip cord always available several colors inexpensive zipped-apart individual wire colors easy convenient keeping track various leads Single-conductor plastic insulated wire also available several sizes colors auto supply stores sure use flexible stranded variety opposed solid-conductor kind cells Ive seen have solder tabs welded cell ends Sometimes may soldered directly together cell cell may used pads wires may easily soldered pays clean straps fine sandpaper SW DOUBLE THROW CENTER OFF SWITCH 3-POSITION R INTERCHANGABLE RESISTER M MOTOR C MOTOR BRUSH CAPACITOR pencil eraser before soldering course always use radio -type solders acid-core types generally solder close cell possible minimize solder strap lengththese arent heavy wire being connected Excess strap length easily cut off Cells massive heat sinks Use sol dering iron both high enough temperature high enough heat capacity allow quick smooth flow solder like tool such Radio Shack 64-2080 handle 64-2082 element 64-2089 tip Avoid use soldering guns vicinity motors extremely strong magnetic field gun transformer may tend de magnetize motor magnets safety battery wiring cells dis charged state Dont soak heat cells Adequate tool heat capacity permits good connection made short-time touch soldering iron careful stripping wire cut strands assure insulation remaining neededsuch wire crosses cell cell Remember case cell negative tenninal around up down cell positive terminal resides small island end Take care cut burn cell outer insulating sleeve may want use smaller soldering tool connections lugs switches connectors Usually solder lugs tight fit 18-gauge larger wire generally tin pre-solder coat both lug stripped wire end lay wire flat against lug reflow solder makes neat adequate joint Sometimes slip some insulating tubing over joint such often done RC connectors Most electric power items made country supplied convenient polar ized cant connect backwards con nectors such made Molex Generally two sizes two-conductor plastic Continued page 62 February 1984 61 revolutionary concept power 1 SV glow plugs model engines used boats cars airplanes NI STARTERITMI uses HeadlockITMI adapter locks onto wont glow plugs start engine Fits Yost pocket comes CIlO charger has LED lights up charging Rechargeable hundreds times gives over hO consecutive starts recharging Available charger Send ad along prepayment receive free shipping handling NI-STARTER$2495 charger Ill OV 220V 12V fast chargerl NI-STARTER$1595 charger Chargers$1295 charger ii 220V orb 2V fast chargeri PLEASE SPECIFY WHICH CHARGER WHEN ORDERINGl 12721 HASKELL LANE BOWIE MARYLAND 207161301464-2260 NEW FOURMOST PRODUCTS FUSELAGE FIXTURE FOURMOST FUSELAGE FIXTURE 5 desrgned ta Astenutieelly align fuselage structures built strings measuring yr eyeballrng Simply slide fear centerine brackets n track ustil alige finrewall tarl vinyl tine bulkheads Clamp fsselagetogetherlightly rubherbands structure wrIl straight track Price 2995 Miter Master Miter Master tour designed usable craftsmae make perfect luiets inn woud accurately sanding pre-setangles squarinafencelAl allowsforprecise9O angles retracts beluw surface Any angle can beset triangular guide using adiacent side cumplemeet ut angle will formed making invaluable fur truss cunstractiun yew cyanuacrylare adhesives require accurately fitted ivints te achieve full strength Minter Master will enable te make naurly FOURMOST PRODUCTS 4040 24th Ave Forest Grove OR 97116 Price $950 Asnentufee bound 503 357-2732 mates have used shown among pictures recently smaller two has become popular connectors available Astro Leisure electron tcs supply houses Another connector style may find use ful single-conductor crimp-on type also pictured require crimping tool proper installation Often 1 wish con nect single wires kind connector connecting plastic fuses mentioned earlier single connectors available already insulated can obtained Radio Shack auto stores hardware stores sure pur chase size suitable 18 16-gauge wire few things should know about both connector types mating fit very tight new often very hard pull needed separate Frequently suddenly let go hands can easily disassemble model wary other hand same con nectors can become quite loose after re peated use happens con nection quality becomes doubtful Fortunately theyre low cost easy replace way some polarized Molex connectors have snap indents purpose being sure stay together catches necessary trim off modeling knife Another connector commonly used purposes mentioned Part 4the charge plug jack parts made Switchcraft available As tro have used years extremely reliable convenient Proper connection polarity shown drawings very helpful con venient flying field fliers use similar charging connectors sometimes neces sary share charging equipment Switchcraft parts common use KRC Now some wiring trivia single 10-in-long conductor 18-gauge lamp cord carrying 10 amperes has voltage drop 0054 volts power dissipation loss 054 watts 20 amps dissipation increases 216 watts wire will probably get warm Use heavier wire case same 10-in-length wire weighs about 013 oz next time somebody flight line acts like knows everything can lay him keep em mind too 6 Prop stops have using prop stops years thanks idea presented Jim Zarehibski Pioneer 15 glider RCM long ago idea prop stop simply locate unpowered prop hQrizontal position landing can fuselage skid prop tip offers distinct advantage fewer broken props importantly fewer bent armature shafts Clearly prop stop almost required model no land ing gear practice prop stop actu Continued page 155 62 Model Aviation 7 N I-STARTER MFG OF NI-STARTER $2495 charger h NEW R/C BOOKLET Answers questions often asked want get started RIG flying PLUS troduces best airplane start GOLDEN FALCON receive copy SEND $200 TO ST CROIX OF PARK FALLS LTD PO Box 279P Park Falls WI 54552 ation standard 22 gauge stranded hook-up wire will adequate Before actually start wiring might want note wiring sketch shows switches appear bottom view next column will have information use resistor shown control box wiring controlling servos speed wire servos some sugges tions insulate control lines flight control handle planes bellcrank system Send items CL Scale Bill Boss 77-06 269th St New Hyde Park NY 11040 Electrics/Kopski "" ~ oaoe 62 ated same servo operates ON OFF switch Refer sketch pictures Parts 2 suggested installation can have vari ations example instead switch being actuated follower prop stop rod switch can directly mounted servo described earlier Also may find some suitable alternative stop-rod material use case sure adjust lengths throws timing prop stop clear prop bet bre switch turns ON switch turns OFF before stop advances prop necessary have small repeatable drag part prop bladethe Great Lakes Model Company PO Box 308 Tawas City Ml 48763 AT-6 SNJ HARVARD Wingspan 63 375 60 Engine 7 lbs Complete List Price $28500 Factory Direct $22800 Michigan residents add 4% salns taa Send SASE fnr Brochare Dealer Inquiries Welcome stop rod does have thrust completely through prop thickness Small motors have three armature poles tend cog ie stop three specific armature positions due pull magnets Mount prop adapter prop stop engages close natural armature resting positions Motors three poles have less tendency cog excep tion some very strong cobalt mag nets prop will tend spin freely case just ease stop prop Sometimes takes little practice adjustment get prop stop repeatedly desired horizontal position persist resistor shown sketch serves purpose braking motor switch goes OFF state resistor instead power switched across stillcoasting motor Without damping re sistor motor prop likely con tinue spinning prop stop withstanding Such coasting armature/prop has con siderable inertiareadily appreciated should engage finger can easily chew up stop rod freewheeling motor its windmill blades acts generator actually develop ing voltage its open terminals resistor forms electrical loada dynamic brakeand limits resulting current surge slow ing stopping generator re LET US KNOW WHERE YOU ARE GOING move please let us know advancesix weeks required change address Attach current MA mailing label check appropriate box mail Subscrip tion Dept Model Aviation 1810 Samuel Morse Dr Reston VA 22090 Check appropriate boxenclosE payment U NEW SuBSCRIPTION U CHANGE OF ADDRESS Non-AMA subscription rates $1800 12 months US possessions elsewhere including G.nada Mexico $2400 US Schools $900 US Libraries $1350 NAME ADDRESS CITY/STATE __________________________________________________ ZIP MODEL AVIATION 1810 SAMUEL MORSE DR RESTON VA 22090 COMPLETE THIS FORM AND ATTACH MAILING LABEL FROM RECENT IssuE 517 362-6078 sistor shown typical valuefrom half twice value usable optimum value varies motor prop plane speed etc may wish try several val ues singular annoyance about such lowvalue resistors availability especially small physical size high wattage rating needed /2 watt plenty Im still looking convenient source Finally prop stops best used directdrive props speed-reduced props gear belt drive cannot stopped easily Fold ing props much better addition protecting both prop prop shaft folders offer considerable aerodynamic drag reductionjust whats needed high-time gliders Next month Part 7 will deal extensively suitable model designs both prin ciple practice Therell some dis cussion construction techniques model size motor size battery size weight flight timesfor sorts models As closing note having referenced sev eral Radio Shack parts supplies have comment Radio Shack has dis quieting practice suddenly dropping items its catalog Items mentioned herein available writing Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 SAFE FLYING IS NO ACCIDENT COMPLETELY FINISHED R/C AIRCRAFT Completely Finished R/ C Aircraft s & Types Radio Engine Only CG Sky riger--63 trainer $22500 Sig Clip Wing J-3 Cah--54 Spon $25000 SEND FOR COMPLETE LIST HOBBY CAPITOL R/C 46 N Oak St Ventura California 93001 FebrUary 1984 155 sIa & Aaaas Han Gal SHaI-Sdy SILICONE 10 foot coils TUBING ID 062 092 125 us POST $/coiI 235 265 325 54t/COIL LARRY DODGE AERO INC 10210 MANNINGSTILLWATER MN 55082