Our look model structures month about strengths weaknesses balsa used planes Part 2 SO FAR AS KNOW no college course test engineering column intended serve its place An approach level would have too pre- co-requisites terms mathe matical skills physics chemistry geome try economics law drafting standards machine shop practices series will concentrate structural test techniques RC models digressions related subjects think necessary keeping mathematics simple first digression EGeorge M Myers structural testing depends knowl edge two things applied loads strength materials Load information comes sourcesthe geometry structure aerodynamics air-passage surfaces eg wind tunnel tests maneuvering characteristics required airplane landing loads ground handling loads engine vibrations environmental loads such temperature humidity effects fuel soaking -1 1 structure con siderations transportation storage going consider applied loads today Information strength materials comes laboratory testing sample pieces materialand no other place Strength materials information collected books Lets check few What stuff called wood June 1944 United States Department Agriculture Forest Service Forest Prod ucts Laboratory Madison WI coop eration University Wisconsin released Report No 1511 Strength Related Properties ofBalsa Quipo Woods June 1945 same group released Report No 1528 Elastic proper ties Wood Youngs Moduli Rigidity Poissons Ratios ofBalsa Quipo Army-Navy-Civil Committee Aircraft Design Criteria issued ANC-1 8 Design WoodAircraft Structures over period years have copy dated 1944 issued U S Government Printing Office Washington DC tables later edition dated June 1951 copies have essential part modeling kit ever since obtained doubt above still available data strength wood valid today have presented some curves summarize some data trip decent college library should reveal dozens newer books containing same old information Woodworkers axiom no such thing average piece wood wood has grain resistance load varies according direction applied load aligns grain birch 15% moisture static tensile strength parallel grain varies 10600 15100 pounds per square inch psi de pending species apply tension perpendicular grain wood will separate between 140 psi softwoods 460 psi birch ex plains should always use ply wood doubler have put bolt through sheet wood always cut gussets grain runs diagonally Fig 1 order make use information books need know something about 56 Model Aviation very graphic demonstration result tangential shrinkage wood goes through dries sign outside Eckler-Lahey Lumber Company South Bend IN tests conducted first thing have know wood bends yields before breaks highest stress wood can resist permanent bending called its proportional limit highest service loads should apply stresses exceed proportional limit stresses case modulus rupture reported ANC-18 2 x 2 x 30-in specimen cut log length parallel grain side parallel radial laid across two supports 28 inches apart annual rings placed horizontal load applied pith center tree side central transverse load applied means hard maple block 313/in wide nose radius 3 over central 2-in arc joined 2-in-radius arcs side Fig 2 reasons wont go now load failure pounds multiplied beam dimensions before failure according standard formula result taken measure tensile stress failure Fbu Maximum Load x 525 tension parallel grain measured pulling specially-shaped block results obtained extremely variable ANC-18 reports average measured value FtuT mum Load/2 x Cross Section Area tension perpendicular grain compression strength parallel grain 2 x 2 x 8 beam cut above load applied top column Fig 3 Load failure divided area column cross section before failure Fcu Maximum Load/4 psi compression parallel grain FIGURE 5 Shear Test Fcu Load produce 1/io-in depression/4 compression perpendicular grain Shear parallel grain measured applying load 2 x 2 x 25 block has cut log grain prallel 2 sides block clamped vise 2 x 2 face projecting 3/4-in load applied paraflel grain -in vise Fig 5 Since strength radial plane about same tangential plane differentiated reports Fsu mum Load/4 psi shear parallel grain test compression perpendicular Wood structurally complex Its fibers grain use 2 x 2 x 6 specimen load long hollow tubes taper closed steel 2 x 2 pad placed middle ends align along length tree length Fig 4 load can placed trunk Additional strips cells known away center tree transverse rays lie radially cross section perpen radial can applied parallel dicular fibers year tree growth rings transverse tangential grows adding circumferential ring either case load greater the spring new cells relatively proportional limit produces crushing thin-walled growing season load crushing load continues thicker-walled cells added required produce 1/ie-in depression has ring difference thickness chosen arbitrarily failing cell walls explains definite lines strength necessary reference delineate growth periods year radial tangential direction next October 1986 57 FIGURE 3LOAD Comressi ye Strength Test Setup 0A takes long time grow tree wet years dry years Windstorms cause breaks heal sort Insects bore holes looking insects birds bore bigger holes Animals fungi other parasites damage tree cut down crashing forest floor dragged away floated down river soaked fuel bounced ground piece wood has history history plays part determining its particular strengths weaknesses Wood living tree has considerable moisture wood converted lumber driedusually kiln free water cell cavities evaporates first has gone remaining internal moisture content will 22 30% weight dry wood wood will have changed dimension strength Further drying will cause shrinkage pri marily tangentially increase strength Longitudinal shrinkage will negligible Wood also hygroscopic will con stantly take give up moisture effort maintain balance rela tive humidity its environment Paints varnishes may change rate exchange takes place will prevent good practice design build according conditions will used will have observed certain doors drawers become sticky weather humid its because woods hygroscopic properties Balsa density 10 lb per cu ft kind used build RC models dried 12% moisture content will have crushing strength about 100 psi com pression parallel grain will 2000 psi tensile strength parallel Continued page 156 58 Model Aviation AA3A * WE ARE SHOOTING DOWN4CUSTOM CUT CONTEST BALSA HIGHBALSAPRICESAll Sheets Piece ed Close Tolerances WITH SUPER QUALITY A Grade Dried ped 100% Satisfaction Guaranteed rious modeler want performance Direct Only must try 4-6 lb balsa ALSA SMELTS 36 48 30I BALSA STICKS 364BLIGHT4-6 LBBASSWOOD 48P6NESTICKS 36 4BHARD MAPLE IS 1/162331/16 114093/163/1626 18181317114318 31322401/16 31810BALSA TRIANGLES36 WOOD363/18 1/430 1/81416233/83/8 1/8 2431/16 1/2141/41/4 281/323493/163/838 1/83/820273/81/2 /162483/32 1/4183/83/8 301/203493/161/246 3/1831617243/83/4 /4 2563/32 3/8121/21/2 351163493/163/468 3/16382332123/4 /323373/32 1/2163/43/4 453/323561/41/442 3/161/23048 1/283371/8 1/806 551/83671/43/849 1/4142637 1/1633749311/8 1/411163/163761/43/480 1/4383042 /BIRCMDOWELS 36 3/3234468 371/8 3/612 18BALSA PLANKS36 1/43853/83/8 601412 34 47 18 09 1/8 35471451/6 1/2162411853/831153/81/2703/83837 62 3/16 11 3/1636262653/163/161116121681/231393/83/480 14 1/4 37396613/16 3/817132883/432201/21/288 16 25 5/163663/16 1/222 3014268133881/23/4188 SPRUCEST8CKS364B 3/832 3/6 388 124 711/4 1/416 2411/232751/164781/8 1/815 1/2 3118 1661/4 31819 2611/243683/324911/8 1/418 24 3/4 31651/4 1/221 30222251/84188 1/1645876 481/4 3/434 44233253/164117BUNDLEDEALS1/8 3/828 293PLYBURCH 48 3/3247884 581/4148244351/44138201/63366653/1831625 34 31I 1/5412525 1/8 488188665/165/182128334953/8428728-1/1643618281/4 1/3212425 3/16493122753/8 3/82737346881/24282203/32336841/4 3/63650 12435 1/4 4110 134 843/8 1/232 46153/324363/8 3/846 63 1/812458 3/8 4165 2263/8 3/442 66TAPEREDSHEETS 3615-1/83367153/8 1/265 78 1/2 4225 2613/8 1521/4265TRAILING EDGE 3610-1/84366751/2 1/26868 12 346888 1/2 1/236 531/4365 1413215-3/16336988SPLVSIRCN 48 BATCHED SHEETS4212 3/44682 3/82885/1611/43910-3/1643661033212570 3/3241001/2 1583/83983/811/24610-1/43366381/812585 18418866 58461/23120 1/2271/10-1/4436890 SPRUCETRIANGLES 36 31612585 316412034 3467103/83368683/83/845 / 1412688 144131___________________5-3/84366251/21/261 5-1/2336540343477 LONE STAR EPOXYNSTANTGLUE5-1/2436865GROOVED LG MOUNTS 90L,l--8961 ,I5/ck29810-3/32448845 BALSA nu LINE srs5981, TS,2985-1/8448485121h@S Cull 8067454394 lOum-6 pmCentmlTme16045962aTSkk9585-3/16448585LITEPLY 483/83/4/1/8/48 30n/5982oa Tl,n6685-1/4448625 j 1/861683/83/4/5/32/48 1/812388123/4/3/16/45 LONE STAR MODELS We accept Visa Master Card pesoaI checks o COD 4-1/8% Ia Teas US curency M/8lmom Order 01080 1623 57th St Lubbock TX 79412 Handling Charge$300 pay UPS Add $200 COD $300 extra PP APO FPO I________________________________ Machines stuff other machines rip rough lumber dried bundled shipped stored cut finished lumber stored again shipped stored dealers shelf selected stored ultimately used construct modelwhich gets moved heated house frozen snowfield es e Stresses 3 4 28 3 3* 4 5 6 3 3&3/4 4 5 6 8 4 5 6 6* 7 4 5 6 6* 7 7* 4 5 6 6W 6* 7 8W 6EW 4 6 7 7* 7* 7&3/4 8 6EW 6 7 4W 5 5W 6 5 6 5 6 5 6 6 78 10*6 6* 7 NEW 126 6* 7 7* 8 13677*8 14677*8 1567 16678 PRICE $149 $179 $189 $199 $199 $209 $219 $229 $239 $239 $279 $459 $659 $949 $239 $299 $389 $489 $689 $989 PYLON RACING 7SN 5*N 8&3/86&3/4 7 7* 8 NEW 8&3/46* 6&3/4 7 7* 7&3/4 97 7* 7&3/4 $279 $299 $289 $289 W Wide blade EW Extra wide N Narrow OLD TIMER SUPPLIES CARBON FIBER COILS CONDENSERS SILK TRANSISTOR IGNITION SYSTEMS TIMERS ETC REPLICA OR WICK ENGINES NE WI! 1/2A PLA YBOY SR FOR 1/2A TEXACO R/C FF ELECTRIC OR SPORT KIT $2995 SPECIALISTS IN CUSTOM COX TEE DEE & REED ENGINES 020S 049S 051S & 09S K & B CUSTOMIZED ENGINES FOR FF OR OLD TIMER ALSO COMPLETE LINE OF U/C & R/C RACING PARTS about clubs put races people very dedicated modeling com munity racers owe big vote thanks would have races Again people sit watch comers flagmen timers great big Thanks Well thats month See races Bill Hager 706 Glen Haven Dr Conroe TX 77385 Structures/Myers Continued page 58 grain will about 2800 psi failure Figure 6 shows average data range balsa wood densities Fig 7 presents data species test data may may coincide material have way using careful use numbers makes some difference wood cut use Figure 8 shows various stresses may found typical wing joint Next time well break some wood such ajoint Remember no such thing average piece wood George M Myers 70 Froehlich Farm Rd Hicksville NY11801 Mel Anderson/Simpson Continued page 61 mile faster world record held England officials meet signed notarized statement giving official time claiming title British commission wrote back said Mel would bring boat England let time would give him official record Otherwise forget middle Depression out question 1939 both Bill Atwood Ira Hassad left Grand Central manufacture engines own Major Moseley came Mel said time design completely new engine After 12 proto types engine finally ready major thought name Super Cyclone would appropriate engines Tuner Save old I~giuOS f06Uc1 0 petSl~4G 9r .. spa PIU5to Over 600 items Send $200 current catalog made both 647 603 cu sizes arrived market early 1940 end year records 60-class engines held Super Cyclone 50000 sold first year World War II began model engine production ceased Mel got manufacturing job war effort war ended Mel told major would like go business himself ideas still better engine Moseley tried talk him staying making engine him Mel declined saying wanted own boss Two years designing setting up production resulted Ander son Spitfire Called engine reviewer Peter Chin Rolls-Royce spark ignition era engine also well ahead its time marvelous piece craftsmanship expensive make timer alone twice parts others engine priced twice cost other 60s market same time smaller displacement engines began gain popularity Anderson Spitfire financial success company soon trouble 1949 two men local news paper walked Mels shop wanted know engine could made inex pensively enough could given away new subscription promotion gimmick glow plug just arriving scene timer coil condenser batteries no longer re quired Mel believed could done set work 045 engine called Baby Spitfire Just development tooling completed paper changed its plans cancelled order Mel decided go ahead production sell through jobbers Mel using glow plug made K&B engines day called John Brodbeck K&B order 10000 plugs What guys doing down asked John ordered 17000 plugs last week Mel realized made mistake cat out bag number engines selling Mel decided begin making own plugs 156 Model Aviation OUR INVENTORY AVERAGES OVER 12000 PROPS! SPECIAL PRO SERIES PITCH BALSARI TE R/C WONDER JUICE Balsarite makes covering stick better also moisture-proofs wood adds little extra structural strength plus W prevents fuelcreep under seams LI fuelproofs engine compartments bALeLI attaches raw dacron k paper tissue CVERITE 420 Babylon Rd Horsham PA 19044 DIA 6 7 8 8* 9 10 10 11 11 11 * 12 13 14 15 16 DECIBAN SOUND LEVEL 95 5* 6NEW$209 10*6 6* 7NEW$239 11*7*8NEW$269 12 7* 8 NEW $299 FOUR-CYCLE TAILORED HELICAL PITCH ORDER BY MAIL OR PHONE 714 8305 162 fSORRY NO COD VISA & MASTERCARD WELCOME DEALER INOUIRIES INVITED ALL PRICES POSTPAID MINIMUM ORDER $1000 FOR INSURANCE ADD $100 ORDERS SHIPPED WITHIN 24 HRS CALIF RESIDENTS ADD 6% TAX
Edition: Model Aviation - 1986/10
Page Numbers: 56, 57, 58, 156
Our look model structures month about strengths weaknesses balsa used planes Part 2 SO FAR AS KNOW no college course test engineering column intended serve its place An approach level would have too pre- co-requisites terms mathe matical skills physics chemistry geome try economics law drafting standards machine shop practices series will concentrate structural test techniques RC models digressions related subjects think necessary keeping mathematics simple first digression EGeorge M Myers structural testing depends knowl edge two things applied loads strength materials Load information comes sourcesthe geometry structure aerodynamics air-passage surfaces eg wind tunnel tests maneuvering characteristics required airplane landing loads ground handling loads engine vibrations environmental loads such temperature humidity effects fuel soaking -1 1 structure con siderations transportation storage going consider applied loads today Information strength materials comes laboratory testing sample pieces materialand no other place Strength materials information collected books Lets check few What stuff called wood June 1944 United States Department Agriculture Forest Service Forest Prod ucts Laboratory Madison WI coop eration University Wisconsin released Report No 1511 Strength Related Properties ofBalsa Quipo Woods June 1945 same group released Report No 1528 Elastic proper ties Wood Youngs Moduli Rigidity Poissons Ratios ofBalsa Quipo Army-Navy-Civil Committee Aircraft Design Criteria issued ANC-1 8 Design WoodAircraft Structures over period years have copy dated 1944 issued U S Government Printing Office Washington DC tables later edition dated June 1951 copies have essential part modeling kit ever since obtained doubt above still available data strength wood valid today have presented some curves summarize some data trip decent college library should reveal dozens newer books containing same old information Woodworkers axiom no such thing average piece wood wood has grain resistance load varies according direction applied load aligns grain birch 15% moisture static tensile strength parallel grain varies 10600 15100 pounds per square inch psi de pending species apply tension perpendicular grain wood will separate between 140 psi softwoods 460 psi birch ex plains should always use ply wood doubler have put bolt through sheet wood always cut gussets grain runs diagonally Fig 1 order make use information books need know something about 56 Model Aviation very graphic demonstration result tangential shrinkage wood goes through dries sign outside Eckler-Lahey Lumber Company South Bend IN tests conducted first thing have know wood bends yields before breaks highest stress wood can resist permanent bending called its proportional limit highest service loads should apply stresses exceed proportional limit stresses case modulus rupture reported ANC-18 2 x 2 x 30-in specimen cut log length parallel grain side parallel radial laid across two supports 28 inches apart annual rings placed horizontal load applied pith center tree side central transverse load applied means hard maple block 313/in wide nose radius 3 over central 2-in arc joined 2-in-radius arcs side Fig 2 reasons wont go now load failure pounds multiplied beam dimensions before failure according standard formula result taken measure tensile stress failure Fbu Maximum Load x 525 tension parallel grain measured pulling specially-shaped block results obtained extremely variable ANC-18 reports average measured value FtuT mum Load/2 x Cross Section Area tension perpendicular grain compression strength parallel grain 2 x 2 x 8 beam cut above load applied top column Fig 3 Load failure divided area column cross section before failure Fcu Maximum Load/4 psi compression parallel grain FIGURE 5 Shear Test Fcu Load produce 1/io-in depression/4 compression perpendicular grain Shear parallel grain measured applying load 2 x 2 x 25 block has cut log grain prallel 2 sides block clamped vise 2 x 2 face projecting 3/4-in load applied paraflel grain -in vise Fig 5 Since strength radial plane about same tangential plane differentiated reports Fsu mum Load/4 psi shear parallel grain test compression perpendicular Wood structurally complex Its fibers grain use 2 x 2 x 6 specimen load long hollow tubes taper closed steel 2 x 2 pad placed middle ends align along length tree length Fig 4 load can placed trunk Additional strips cells known away center tree transverse rays lie radially cross section perpen radial can applied parallel dicular fibers year tree growth rings transverse tangential grows adding circumferential ring either case load greater the spring new cells relatively proportional limit produces crushing thin-walled growing season load crushing load continues thicker-walled cells added required produce 1/ie-in depression has ring difference thickness chosen arbitrarily failing cell walls explains definite lines strength necessary reference delineate growth periods year radial tangential direction next October 1986 57 FIGURE 3LOAD Comressi ye Strength Test Setup 0A takes long time grow tree wet years dry years Windstorms cause breaks heal sort Insects bore holes looking insects birds bore bigger holes Animals fungi other parasites damage tree cut down crashing forest floor dragged away floated down river soaked fuel bounced ground piece wood has history history plays part determining its particular strengths weaknesses Wood living tree has considerable moisture wood converted lumber driedusually kiln free water cell cavities evaporates first has gone remaining internal moisture content will 22 30% weight dry wood wood will have changed dimension strength Further drying will cause shrinkage pri marily tangentially increase strength Longitudinal shrinkage will negligible Wood also hygroscopic will con stantly take give up moisture effort maintain balance rela tive humidity its environment Paints varnishes may change rate exchange takes place will prevent good practice design build according conditions will used will have observed certain doors drawers become sticky weather humid its because woods hygroscopic properties Balsa density 10 lb per cu ft kind used build RC models dried 12% moisture content will have crushing strength about 100 psi com pression parallel grain will 2000 psi tensile strength parallel Continued page 156 58 Model Aviation AA3A * WE ARE SHOOTING DOWN4CUSTOM CUT CONTEST BALSA HIGHBALSAPRICESAll Sheets Piece ed Close Tolerances WITH SUPER QUALITY A Grade Dried ped 100% Satisfaction Guaranteed rious modeler want performance Direct Only must try 4-6 lb balsa ALSA SMELTS 36 48 30I BALSA STICKS 364BLIGHT4-6 LBBASSWOOD 48P6NESTICKS 36 4BHARD MAPLE IS 1/162331/16 114093/163/1626 18181317114318 31322401/16 31810BALSA TRIANGLES36 WOOD363/18 1/430 1/81416233/83/8 1/8 2431/16 1/2141/41/4 281/323493/163/838 1/83/820273/81/2 /162483/32 1/4183/83/8 301/203493/161/246 3/1831617243/83/4 /4 2563/32 3/8121/21/2 351163493/163/468 3/16382332123/4 /323373/32 1/2163/43/4 453/323561/41/442 3/161/23048 1/283371/8 1/806 551/83671/43/849 1/4142637 1/1633749311/8 1/411163/163761/43/480 1/4383042 /BIRCMDOWELS 36 3/3234468 371/8 3/612 18BALSA PLANKS36 1/43853/83/8 601412 34 47 18 09 1/8 35471451/6 1/2162411853/831153/81/2703/83837 62 3/16 11 3/1636262653/163/161116121681/231393/83/480 14 1/4 37396613/16 3/817132883/432201/21/288 16 25 5/163663/16 1/222 3014268133881/23/4188 SPRUCEST8CKS364B 3/832 3/6 388 124 711/4 1/416 2411/232751/164781/8 1/815 1/2 3118 1661/4 31819 2611/243683/324911/8 1/418 24 3/4 31651/4 1/221 30222251/84188 1/1645876 481/4 3/434 44233253/164117BUNDLEDEALS1/8 3/828 293PLYBURCH 48 3/3247884 581/4148244351/44138201/63366653/1831625 34 31I 1/5412525 1/8 488188665/165/182128334953/8428728-1/1643618281/4 1/3212425 3/16493122753/8 3/82737346881/24282203/32336841/4 3/63650 12435 1/4 4110 134 843/8 1/232 46153/324363/8 3/846 63 1/812458 3/8 4165 2263/8 3/442 66TAPEREDSHEETS 3615-1/83367153/8 1/265 78 1/2 4225 2613/8 1521/4265TRAILING EDGE 3610-1/84366751/2 1/26868 12 346888 1/2 1/236 531/4365 1413215-3/16336988SPLVSIRCN 48 BATCHED SHEETS4212 3/44682 3/82885/1611/43910-3/1643661033212570 3/3241001/2 1583/83983/811/24610-1/43366381/812585 18418866 58461/23120 1/2271/10-1/4436890 SPRUCETRIANGLES 36 31612585 316412034 3467103/83368683/83/845 / 1412688 144131___________________5-3/84366251/21/261 5-1/2336540343477 LONE STAR EPOXYNSTANTGLUE5-1/2436865GROOVED LG MOUNTS 90L,l--8961 ,I5/ck29810-3/32448845 BALSA nu LINE srs5981, TS,2985-1/8448485121h@S Cull 8067454394 lOum-6 pmCentmlTme16045962aTSkk9585-3/16448585LITEPLY 483/83/4/1/8/48 30n/5982oa Tl,n6685-1/4448625 j 1/861683/83/4/5/32/48 1/812388123/4/3/16/45 LONE STAR MODELS We accept Visa Master Card pesoaI checks o COD 4-1/8% Ia Teas US curency M/8lmom Order 01080 1623 57th St Lubbock TX 79412 Handling Charge$300 pay UPS Add $200 COD $300 extra PP APO FPO I________________________________ Machines stuff other machines rip rough lumber dried bundled shipped stored cut finished lumber stored again shipped stored dealers shelf selected stored ultimately used construct modelwhich gets moved heated house frozen snowfield es e Stresses 3 4 28 3 3* 4 5 6 3 3&3/4 4 5 6 8 4 5 6 6* 7 4 5 6 6* 7 7* 4 5 6 6W 6* 7 8W 6EW 4 6 7 7* 7* 7&3/4 8 6EW 6 7 4W 5 5W 6 5 6 5 6 5 6 6 78 10*6 6* 7 NEW 126 6* 7 7* 8 13677*8 14677*8 1567 16678 PRICE $149 $179 $189 $199 $199 $209 $219 $229 $239 $239 $279 $459 $659 $949 $239 $299 $389 $489 $689 $989 PYLON RACING 7SN 5*N 8&3/86&3/4 7 7* 8 NEW 8&3/46* 6&3/4 7 7* 7&3/4 97 7* 7&3/4 $279 $299 $289 $289 W Wide blade EW Extra wide N Narrow OLD TIMER SUPPLIES CARBON FIBER COILS CONDENSERS SILK TRANSISTOR IGNITION SYSTEMS TIMERS ETC REPLICA OR WICK ENGINES NE WI! 1/2A PLA YBOY SR FOR 1/2A TEXACO R/C FF ELECTRIC OR SPORT KIT $2995 SPECIALISTS IN CUSTOM COX TEE DEE & REED ENGINES 020S 049S 051S & 09S K & B CUSTOMIZED ENGINES FOR FF OR OLD TIMER ALSO COMPLETE LINE OF U/C & R/C RACING PARTS about clubs put races people very dedicated modeling com munity racers owe big vote thanks would have races Again people sit watch comers flagmen timers great big Thanks Well thats month See races Bill Hager 706 Glen Haven Dr Conroe TX 77385 Structures/Myers Continued page 58 grain will about 2800 psi failure Figure 6 shows average data range balsa wood densities Fig 7 presents data species test data may may coincide material have way using careful use numbers makes some difference wood cut use Figure 8 shows various stresses may found typical wing joint Next time well break some wood such ajoint Remember no such thing average piece wood George M Myers 70 Froehlich Farm Rd Hicksville NY11801 Mel Anderson/Simpson Continued page 61 mile faster world record held England officials meet signed notarized statement giving official time claiming title British commission wrote back said Mel would bring boat England let time would give him official record Otherwise forget middle Depression out question 1939 both Bill Atwood Ira Hassad left Grand Central manufacture engines own Major Moseley came Mel said time design completely new engine After 12 proto types engine finally ready major thought name Super Cyclone would appropriate engines Tuner Save old I~giuOS f06Uc1 0 petSl~4G 9r .. spa PIU5to Over 600 items Send $200 current catalog made both 647 603 cu sizes arrived market early 1940 end year records 60-class engines held Super Cyclone 50000 sold first year World War II began model engine production ceased Mel got manufacturing job war effort war ended Mel told major would like go business himself ideas still better engine Moseley tried talk him staying making engine him Mel declined saying wanted own boss Two years designing setting up production resulted Ander son Spitfire Called engine reviewer Peter Chin Rolls-Royce spark ignition era engine also well ahead its time marvelous piece craftsmanship expensive make timer alone twice parts others engine priced twice cost other 60s market same time smaller displacement engines began gain popularity Anderson Spitfire financial success company soon trouble 1949 two men local news paper walked Mels shop wanted know engine could made inex pensively enough could given away new subscription promotion gimmick glow plug just arriving scene timer coil condenser batteries no longer re quired Mel believed could done set work 045 engine called Baby Spitfire Just development tooling completed paper changed its plans cancelled order Mel decided go ahead production sell through jobbers Mel using glow plug made K&B engines day called John Brodbeck K&B order 10000 plugs What guys doing down asked John ordered 17000 plugs last week Mel realized made mistake cat out bag number engines selling Mel decided begin making own plugs 156 Model Aviation OUR INVENTORY AVERAGES OVER 12000 PROPS! SPECIAL PRO SERIES PITCH BALSARI TE R/C WONDER JUICE Balsarite makes covering stick better also moisture-proofs wood adds little extra structural strength plus W prevents fuelcreep under seams LI fuelproofs engine compartments bALeLI attaches raw dacron k paper tissue CVERITE 420 Babylon Rd Horsham PA 19044 DIA 6 7 8 8* 9 10 10 11 11 11 * 12 13 14 15 16 DECIBAN SOUND LEVEL 95 5* 6NEW$209 10*6 6* 7NEW$239 11*7*8NEW$269 12 7* 8 NEW $299 FOUR-CYCLE TAILORED HELICAL PITCH ORDER BY MAIL OR PHONE 714 8305 162 fSORRY NO COD VISA & MASTERCARD WELCOME DEALER INOUIRIES INVITED ALL PRICES POSTPAID MINIMUM ORDER $1000 FOR INSURANCE ADD $100 ORDERS SHIPPED WITHIN 24 HRS CALIF RESIDENTS ADD 6% TAX
Edition: Model Aviation - 1986/10
Page Numbers: 56, 57, 58, 156
Our look model structures month about strengths weaknesses balsa used planes Part 2 SO FAR AS KNOW no college course test engineering column intended serve its place An approach level would have too pre- co-requisites terms mathe matical skills physics chemistry geome try economics law drafting standards machine shop practices series will concentrate structural test techniques RC models digressions related subjects think necessary keeping mathematics simple first digression EGeorge M Myers structural testing depends knowl edge two things applied loads strength materials Load information comes sourcesthe geometry structure aerodynamics air-passage surfaces eg wind tunnel tests maneuvering characteristics required airplane landing loads ground handling loads engine vibrations environmental loads such temperature humidity effects fuel soaking -1 1 structure con siderations transportation storage going consider applied loads today Information strength materials comes laboratory testing sample pieces materialand no other place Strength materials information collected books Lets check few What stuff called wood June 1944 United States Department Agriculture Forest Service Forest Prod ucts Laboratory Madison WI coop eration University Wisconsin released Report No 1511 Strength Related Properties ofBalsa Quipo Woods June 1945 same group released Report No 1528 Elastic proper ties Wood Youngs Moduli Rigidity Poissons Ratios ofBalsa Quipo Army-Navy-Civil Committee Aircraft Design Criteria issued ANC-1 8 Design WoodAircraft Structures over period years have copy dated 1944 issued U S Government Printing Office Washington DC tables later edition dated June 1951 copies have essential part modeling kit ever since obtained doubt above still available data strength wood valid today have presented some curves summarize some data trip decent college library should reveal dozens newer books containing same old information Woodworkers axiom no such thing average piece wood wood has grain resistance load varies according direction applied load aligns grain birch 15% moisture static tensile strength parallel grain varies 10600 15100 pounds per square inch psi de pending species apply tension perpendicular grain wood will separate between 140 psi softwoods 460 psi birch ex plains should always use ply wood doubler have put bolt through sheet wood always cut gussets grain runs diagonally Fig 1 order make use information books need know something about 56 Model Aviation very graphic demonstration result tangential shrinkage wood goes through dries sign outside Eckler-Lahey Lumber Company South Bend IN tests conducted first thing have know wood bends yields before breaks highest stress wood can resist permanent bending called its proportional limit highest service loads should apply stresses exceed proportional limit stresses case modulus rupture reported ANC-18 2 x 2 x 30-in specimen cut log length parallel grain side parallel radial laid across two supports 28 inches apart annual rings placed horizontal load applied pith center tree side central transverse load applied means hard maple block 313/in wide nose radius 3 over central 2-in arc joined 2-in-radius arcs side Fig 2 reasons wont go now load failure pounds multiplied beam dimensions before failure according standard formula result taken measure tensile stress failure Fbu Maximum Load x 525 tension parallel grain measured pulling specially-shaped block results obtained extremely variable ANC-18 reports average measured value FtuT mum Load/2 x Cross Section Area tension perpendicular grain compression strength parallel grain 2 x 2 x 8 beam cut above load applied top column Fig 3 Load failure divided area column cross section before failure Fcu Maximum Load/4 psi compression parallel grain FIGURE 5 Shear Test Fcu Load produce 1/io-in depression/4 compression perpendicular grain Shear parallel grain measured applying load 2 x 2 x 25 block has cut log grain prallel 2 sides block clamped vise 2 x 2 face projecting 3/4-in load applied paraflel grain -in vise Fig 5 Since strength radial plane about same tangential plane differentiated reports Fsu mum Load/4 psi shear parallel grain test compression perpendicular Wood structurally complex Its fibers grain use 2 x 2 x 6 specimen load long hollow tubes taper closed steel 2 x 2 pad placed middle ends align along length tree length Fig 4 load can placed trunk Additional strips cells known away center tree transverse rays lie radially cross section perpen radial can applied parallel dicular fibers year tree growth rings transverse tangential grows adding circumferential ring either case load greater the spring new cells relatively proportional limit produces crushing thin-walled growing season load crushing load continues thicker-walled cells added required produce 1/ie-in depression has ring difference thickness chosen arbitrarily failing cell walls explains definite lines strength necessary reference delineate growth periods year radial tangential direction next October 1986 57 FIGURE 3LOAD Comressi ye Strength Test Setup 0A takes long time grow tree wet years dry years Windstorms cause breaks heal sort Insects bore holes looking insects birds bore bigger holes Animals fungi other parasites damage tree cut down crashing forest floor dragged away floated down river soaked fuel bounced ground piece wood has history history plays part determining its particular strengths weaknesses Wood living tree has considerable moisture wood converted lumber driedusually kiln free water cell cavities evaporates first has gone remaining internal moisture content will 22 30% weight dry wood wood will have changed dimension strength Further drying will cause shrinkage pri marily tangentially increase strength Longitudinal shrinkage will negligible Wood also hygroscopic will con stantly take give up moisture effort maintain balance rela tive humidity its environment Paints varnishes may change rate exchange takes place will prevent good practice design build according conditions will used will have observed certain doors drawers become sticky weather humid its because woods hygroscopic properties Balsa density 10 lb per cu ft kind used build RC models dried 12% moisture content will have crushing strength about 100 psi com pression parallel grain will 2000 psi tensile strength parallel Continued page 156 58 Model Aviation AA3A * WE ARE SHOOTING DOWN4CUSTOM CUT CONTEST BALSA HIGHBALSAPRICESAll Sheets Piece ed Close Tolerances WITH SUPER QUALITY A Grade Dried ped 100% Satisfaction Guaranteed rious modeler want performance Direct Only must try 4-6 lb balsa ALSA SMELTS 36 48 30I BALSA STICKS 364BLIGHT4-6 LBBASSWOOD 48P6NESTICKS 36 4BHARD MAPLE IS 1/162331/16 114093/163/1626 18181317114318 31322401/16 31810BALSA TRIANGLES36 WOOD363/18 1/430 1/81416233/83/8 1/8 2431/16 1/2141/41/4 281/323493/163/838 1/83/820273/81/2 /162483/32 1/4183/83/8 301/203493/161/246 3/1831617243/83/4 /4 2563/32 3/8121/21/2 351163493/163/468 3/16382332123/4 /323373/32 1/2163/43/4 453/323561/41/442 3/161/23048 1/283371/8 1/806 551/83671/43/849 1/4142637 1/1633749311/8 1/411163/163761/43/480 1/4383042 /BIRCMDOWELS 36 3/3234468 371/8 3/612 18BALSA PLANKS36 1/43853/83/8 601412 34 47 18 09 1/8 35471451/6 1/2162411853/831153/81/2703/83837 62 3/16 11 3/1636262653/163/161116121681/231393/83/480 14 1/4 37396613/16 3/817132883/432201/21/288 16 25 5/163663/16 1/222 3014268133881/23/4188 SPRUCEST8CKS364B 3/832 3/6 388 124 711/4 1/416 2411/232751/164781/8 1/815 1/2 3118 1661/4 31819 2611/243683/324911/8 1/418 24 3/4 31651/4 1/221 30222251/84188 1/1645876 481/4 3/434 44233253/164117BUNDLEDEALS1/8 3/828 293PLYBURCH 48 3/3247884 581/4148244351/44138201/63366653/1831625 34 31I 1/5412525 1/8 488188665/165/182128334953/8428728-1/1643618281/4 1/3212425 3/16493122753/8 3/82737346881/24282203/32336841/4 3/63650 12435 1/4 4110 134 843/8 1/232 46153/324363/8 3/846 63 1/812458 3/8 4165 2263/8 3/442 66TAPEREDSHEETS 3615-1/83367153/8 1/265 78 1/2 4225 2613/8 1521/4265TRAILING EDGE 3610-1/84366751/2 1/26868 12 346888 1/2 1/236 531/4365 1413215-3/16336988SPLVSIRCN 48 BATCHED SHEETS4212 3/44682 3/82885/1611/43910-3/1643661033212570 3/3241001/2 1583/83983/811/24610-1/43366381/812585 18418866 58461/23120 1/2271/10-1/4436890 SPRUCETRIANGLES 36 31612585 316412034 3467103/83368683/83/845 / 1412688 144131___________________5-3/84366251/21/261 5-1/2336540343477 LONE STAR EPOXYNSTANTGLUE5-1/2436865GROOVED LG MOUNTS 90L,l--8961 ,I5/ck29810-3/32448845 BALSA nu LINE srs5981, TS,2985-1/8448485121h@S Cull 8067454394 lOum-6 pmCentmlTme16045962aTSkk9585-3/16448585LITEPLY 483/83/4/1/8/48 30n/5982oa Tl,n6685-1/4448625 j 1/861683/83/4/5/32/48 1/812388123/4/3/16/45 LONE STAR MODELS We accept Visa Master Card pesoaI checks o COD 4-1/8% Ia Teas US curency M/8lmom Order 01080 1623 57th St Lubbock TX 79412 Handling Charge$300 pay UPS Add $200 COD $300 extra PP APO FPO I________________________________ Machines stuff other machines rip rough lumber dried bundled shipped stored cut finished lumber stored again shipped stored dealers shelf selected stored ultimately used construct modelwhich gets moved heated house frozen snowfield es e Stresses 3 4 28 3 3* 4 5 6 3 3&3/4 4 5 6 8 4 5 6 6* 7 4 5 6 6* 7 7* 4 5 6 6W 6* 7 8W 6EW 4 6 7 7* 7* 7&3/4 8 6EW 6 7 4W 5 5W 6 5 6 5 6 5 6 6 78 10*6 6* 7 NEW 126 6* 7 7* 8 13677*8 14677*8 1567 16678 PRICE $149 $179 $189 $199 $199 $209 $219 $229 $239 $239 $279 $459 $659 $949 $239 $299 $389 $489 $689 $989 PYLON RACING 7SN 5*N 8&3/86&3/4 7 7* 8 NEW 8&3/46* 6&3/4 7 7* 7&3/4 97 7* 7&3/4 $279 $299 $289 $289 W Wide blade EW Extra wide N Narrow OLD TIMER SUPPLIES CARBON FIBER COILS CONDENSERS SILK TRANSISTOR IGNITION SYSTEMS TIMERS ETC REPLICA OR WICK ENGINES NE WI! 1/2A PLA YBOY SR FOR 1/2A TEXACO R/C FF ELECTRIC OR SPORT KIT $2995 SPECIALISTS IN CUSTOM COX TEE DEE & REED ENGINES 020S 049S 051S & 09S K & B CUSTOMIZED ENGINES FOR FF OR OLD TIMER ALSO COMPLETE LINE OF U/C & R/C RACING PARTS about clubs put races people very dedicated modeling com munity racers owe big vote thanks would have races Again people sit watch comers flagmen timers great big Thanks Well thats month See races Bill Hager 706 Glen Haven Dr Conroe TX 77385 Structures/Myers Continued page 58 grain will about 2800 psi failure Figure 6 shows average data range balsa wood densities Fig 7 presents data species test data may may coincide material have way using careful use numbers makes some difference wood cut use Figure 8 shows various stresses may found typical wing joint Next time well break some wood such ajoint Remember no such thing average piece wood George M Myers 70 Froehlich Farm Rd Hicksville NY11801 Mel Anderson/Simpson Continued page 61 mile faster world record held England officials meet signed notarized statement giving official time claiming title British commission wrote back said Mel would bring boat England let time would give him official record Otherwise forget middle Depression out question 1939 both Bill Atwood Ira Hassad left Grand Central manufacture engines own Major Moseley came Mel said time design completely new engine After 12 proto types engine finally ready major thought name Super Cyclone would appropriate engines Tuner Save old I~giuOS f06Uc1 0 petSl~4G 9r .. spa PIU5to Over 600 items Send $200 current catalog made both 647 603 cu sizes arrived market early 1940 end year records 60-class engines held Super Cyclone 50000 sold first year World War II began model engine production ceased Mel got manufacturing job war effort war ended Mel told major would like go business himself ideas still better engine Moseley tried talk him staying making engine him Mel declined saying wanted own boss Two years designing setting up production resulted Ander son Spitfire Called engine reviewer Peter Chin Rolls-Royce spark ignition era engine also well ahead its time marvelous piece craftsmanship expensive make timer alone twice parts others engine priced twice cost other 60s market same time smaller displacement engines began gain popularity Anderson Spitfire financial success company soon trouble 1949 two men local news paper walked Mels shop wanted know engine could made inex pensively enough could given away new subscription promotion gimmick glow plug just arriving scene timer coil condenser batteries no longer re quired Mel believed could done set work 045 engine called Baby Spitfire Just development tooling completed paper changed its plans cancelled order Mel decided go ahead production sell through jobbers Mel using glow plug made K&B engines day called John Brodbeck K&B order 10000 plugs What guys doing down asked John ordered 17000 plugs last week Mel realized made mistake cat out bag number engines selling Mel decided begin making own plugs 156 Model Aviation OUR INVENTORY AVERAGES OVER 12000 PROPS! SPECIAL PRO SERIES PITCH BALSARI TE R/C WONDER JUICE Balsarite makes covering stick better also moisture-proofs wood adds little extra structural strength plus W prevents fuelcreep under seams LI fuelproofs engine compartments bALeLI attaches raw dacron k paper tissue CVERITE 420 Babylon Rd Horsham PA 19044 DIA 6 7 8 8* 9 10 10 11 11 11 * 12 13 14 15 16 DECIBAN SOUND LEVEL 95 5* 6NEW$209 10*6 6* 7NEW$239 11*7*8NEW$269 12 7* 8 NEW $299 FOUR-CYCLE TAILORED HELICAL PITCH ORDER BY MAIL OR PHONE 714 8305 162 fSORRY NO COD VISA & MASTERCARD WELCOME DEALER INOUIRIES INVITED ALL PRICES POSTPAID MINIMUM ORDER $1000 FOR INSURANCE ADD $100 ORDERS SHIPPED WITHIN 24 HRS CALIF RESIDENTS ADD 6% TAX
Edition: Model Aviation - 1986/10
Page Numbers: 56, 57, 58, 156
Our look model structures month about strengths weaknesses balsa used planes Part 2 SO FAR AS KNOW no college course test engineering column intended serve its place An approach level would have too pre- co-requisites terms mathe matical skills physics chemistry geome try economics law drafting standards machine shop practices series will concentrate structural test techniques RC models digressions related subjects think necessary keeping mathematics simple first digression EGeorge M Myers structural testing depends knowl edge two things applied loads strength materials Load information comes sourcesthe geometry structure aerodynamics air-passage surfaces eg wind tunnel tests maneuvering characteristics required airplane landing loads ground handling loads engine vibrations environmental loads such temperature humidity effects fuel soaking -1 1 structure con siderations transportation storage going consider applied loads today Information strength materials comes laboratory testing sample pieces materialand no other place Strength materials information collected books Lets check few What stuff called wood June 1944 United States Department Agriculture Forest Service Forest Prod ucts Laboratory Madison WI coop eration University Wisconsin released Report No 1511 Strength Related Properties ofBalsa Quipo Woods June 1945 same group released Report No 1528 Elastic proper ties Wood Youngs Moduli Rigidity Poissons Ratios ofBalsa Quipo Army-Navy-Civil Committee Aircraft Design Criteria issued ANC-1 8 Design WoodAircraft Structures over period years have copy dated 1944 issued U S Government Printing Office Washington DC tables later edition dated June 1951 copies have essential part modeling kit ever since obtained doubt above still available data strength wood valid today have presented some curves summarize some data trip decent college library should reveal dozens newer books containing same old information Woodworkers axiom no such thing average piece wood wood has grain resistance load varies according direction applied load aligns grain birch 15% moisture static tensile strength parallel grain varies 10600 15100 pounds per square inch psi de pending species apply tension perpendicular grain wood will separate between 140 psi softwoods 460 psi birch ex plains should always use ply wood doubler have put bolt through sheet wood always cut gussets grain runs diagonally Fig 1 order make use information books need know something about 56 Model Aviation very graphic demonstration result tangential shrinkage wood goes through dries sign outside Eckler-Lahey Lumber Company South Bend IN tests conducted first thing have know wood bends yields before breaks highest stress wood can resist permanent bending called its proportional limit highest service loads should apply stresses exceed proportional limit stresses case modulus rupture reported ANC-18 2 x 2 x 30-in specimen cut log length parallel grain side parallel radial laid across two supports 28 inches apart annual rings placed horizontal load applied pith center tree side central transverse load applied means hard maple block 313/in wide nose radius 3 over central 2-in arc joined 2-in-radius arcs side Fig 2 reasons wont go now load failure pounds multiplied beam dimensions before failure according standard formula result taken measure tensile stress failure Fbu Maximum Load x 525 tension parallel grain measured pulling specially-shaped block results obtained extremely variable ANC-18 reports average measured value FtuT mum Load/2 x Cross Section Area tension perpendicular grain compression strength parallel grain 2 x 2 x 8 beam cut above load applied top column Fig 3 Load failure divided area column cross section before failure Fcu Maximum Load/4 psi compression parallel grain FIGURE 5 Shear Test Fcu Load produce 1/io-in depression/4 compression perpendicular grain Shear parallel grain measured applying load 2 x 2 x 25 block has cut log grain prallel 2 sides block clamped vise 2 x 2 face projecting 3/4-in load applied paraflel grain -in vise Fig 5 Since strength radial plane about same tangential plane differentiated reports Fsu mum Load/4 psi shear parallel grain test compression perpendicular Wood structurally complex Its fibers grain use 2 x 2 x 6 specimen load long hollow tubes taper closed steel 2 x 2 pad placed middle ends align along length tree length Fig 4 load can placed trunk Additional strips cells known away center tree transverse rays lie radially cross section perpen radial can applied parallel dicular fibers year tree growth rings transverse tangential grows adding circumferential ring either case load greater the spring new cells relatively proportional limit produces crushing thin-walled growing season load crushing load continues thicker-walled cells added required produce 1/ie-in depression has ring difference thickness chosen arbitrarily failing cell walls explains definite lines strength necessary reference delineate growth periods year radial tangential direction next October 1986 57 FIGURE 3LOAD Comressi ye Strength Test Setup 0A takes long time grow tree wet years dry years Windstorms cause breaks heal sort Insects bore holes looking insects birds bore bigger holes Animals fungi other parasites damage tree cut down crashing forest floor dragged away floated down river soaked fuel bounced ground piece wood has history history plays part determining its particular strengths weaknesses Wood living tree has considerable moisture wood converted lumber driedusually kiln free water cell cavities evaporates first has gone remaining internal moisture content will 22 30% weight dry wood wood will have changed dimension strength Further drying will cause shrinkage pri marily tangentially increase strength Longitudinal shrinkage will negligible Wood also hygroscopic will con stantly take give up moisture effort maintain balance rela tive humidity its environment Paints varnishes may change rate exchange takes place will prevent good practice design build according conditions will used will have observed certain doors drawers become sticky weather humid its because woods hygroscopic properties Balsa density 10 lb per cu ft kind used build RC models dried 12% moisture content will have crushing strength about 100 psi com pression parallel grain will 2000 psi tensile strength parallel Continued page 156 58 Model Aviation AA3A * WE ARE SHOOTING DOWN4CUSTOM CUT CONTEST BALSA HIGHBALSAPRICESAll Sheets Piece ed Close Tolerances WITH SUPER QUALITY A Grade Dried ped 100% Satisfaction Guaranteed rious modeler want performance Direct Only must try 4-6 lb balsa ALSA SMELTS 36 48 30I BALSA STICKS 364BLIGHT4-6 LBBASSWOOD 48P6NESTICKS 36 4BHARD MAPLE IS 1/162331/16 114093/163/1626 18181317114318 31322401/16 31810BALSA TRIANGLES36 WOOD363/18 1/430 1/81416233/83/8 1/8 2431/16 1/2141/41/4 281/323493/163/838 1/83/820273/81/2 /162483/32 1/4183/83/8 301/203493/161/246 3/1831617243/83/4 /4 2563/32 3/8121/21/2 351163493/163/468 3/16382332123/4 /323373/32 1/2163/43/4 453/323561/41/442 3/161/23048 1/283371/8 1/806 551/83671/43/849 1/4142637 1/1633749311/8 1/411163/163761/43/480 1/4383042 /BIRCMDOWELS 36 3/3234468 371/8 3/612 18BALSA PLANKS36 1/43853/83/8 601412 34 47 18 09 1/8 35471451/6 1/2162411853/831153/81/2703/83837 62 3/16 11 3/1636262653/163/161116121681/231393/83/480 14 1/4 37396613/16 3/817132883/432201/21/288 16 25 5/163663/16 1/222 3014268133881/23/4188 SPRUCEST8CKS364B 3/832 3/6 388 124 711/4 1/416 2411/232751/164781/8 1/815 1/2 3118 1661/4 31819 2611/243683/324911/8 1/418 24 3/4 31651/4 1/221 30222251/84188 1/1645876 481/4 3/434 44233253/164117BUNDLEDEALS1/8 3/828 293PLYBURCH 48 3/3247884 581/4148244351/44138201/63366653/1831625 34 31I 1/5412525 1/8 488188665/165/182128334953/8428728-1/1643618281/4 1/3212425 3/16493122753/8 3/82737346881/24282203/32336841/4 3/63650 12435 1/4 4110 134 843/8 1/232 46153/324363/8 3/846 63 1/812458 3/8 4165 2263/8 3/442 66TAPEREDSHEETS 3615-1/83367153/8 1/265 78 1/2 4225 2613/8 1521/4265TRAILING EDGE 3610-1/84366751/2 1/26868 12 346888 1/2 1/236 531/4365 1413215-3/16336988SPLVSIRCN 48 BATCHED SHEETS4212 3/44682 3/82885/1611/43910-3/1643661033212570 3/3241001/2 1583/83983/811/24610-1/43366381/812585 18418866 58461/23120 1/2271/10-1/4436890 SPRUCETRIANGLES 36 31612585 316412034 3467103/83368683/83/845 / 1412688 144131___________________5-3/84366251/21/261 5-1/2336540343477 LONE STAR EPOXYNSTANTGLUE5-1/2436865GROOVED LG MOUNTS 90L,l--8961 ,I5/ck29810-3/32448845 BALSA nu LINE srs5981, TS,2985-1/8448485121h@S Cull 8067454394 lOum-6 pmCentmlTme16045962aTSkk9585-3/16448585LITEPLY 483/83/4/1/8/48 30n/5982oa Tl,n6685-1/4448625 j 1/861683/83/4/5/32/48 1/812388123/4/3/16/45 LONE STAR MODELS We accept Visa Master Card pesoaI checks o COD 4-1/8% Ia Teas US curency M/8lmom Order 01080 1623 57th St Lubbock TX 79412 Handling Charge$300 pay UPS Add $200 COD $300 extra PP APO FPO I________________________________ Machines stuff other machines rip rough lumber dried bundled shipped stored cut finished lumber stored again shipped stored dealers shelf selected stored ultimately used construct modelwhich gets moved heated house frozen snowfield es e Stresses 3 4 28 3 3* 4 5 6 3 3&3/4 4 5 6 8 4 5 6 6* 7 4 5 6 6* 7 7* 4 5 6 6W 6* 7 8W 6EW 4 6 7 7* 7* 7&3/4 8 6EW 6 7 4W 5 5W 6 5 6 5 6 5 6 6 78 10*6 6* 7 NEW 126 6* 7 7* 8 13677*8 14677*8 1567 16678 PRICE $149 $179 $189 $199 $199 $209 $219 $229 $239 $239 $279 $459 $659 $949 $239 $299 $389 $489 $689 $989 PYLON RACING 7SN 5*N 8&3/86&3/4 7 7* 8 NEW 8&3/46* 6&3/4 7 7* 7&3/4 97 7* 7&3/4 $279 $299 $289 $289 W Wide blade EW Extra wide N Narrow OLD TIMER SUPPLIES CARBON FIBER COILS CONDENSERS SILK TRANSISTOR IGNITION SYSTEMS TIMERS ETC REPLICA OR WICK ENGINES NE WI! 1/2A PLA YBOY SR FOR 1/2A TEXACO R/C FF ELECTRIC OR SPORT KIT $2995 SPECIALISTS IN CUSTOM COX TEE DEE & REED ENGINES 020S 049S 051S & 09S K & B CUSTOMIZED ENGINES FOR FF OR OLD TIMER ALSO COMPLETE LINE OF U/C & R/C RACING PARTS about clubs put races people very dedicated modeling com munity racers owe big vote thanks would have races Again people sit watch comers flagmen timers great big Thanks Well thats month See races Bill Hager 706 Glen Haven Dr Conroe TX 77385 Structures/Myers Continued page 58 grain will about 2800 psi failure Figure 6 shows average data range balsa wood densities Fig 7 presents data species test data may may coincide material have way using careful use numbers makes some difference wood cut use Figure 8 shows various stresses may found typical wing joint Next time well break some wood such ajoint Remember no such thing average piece wood George M Myers 70 Froehlich Farm Rd Hicksville NY11801 Mel Anderson/Simpson Continued page 61 mile faster world record held England officials meet signed notarized statement giving official time claiming title British commission wrote back said Mel would bring boat England let time would give him official record Otherwise forget middle Depression out question 1939 both Bill Atwood Ira Hassad left Grand Central manufacture engines own Major Moseley came Mel said time design completely new engine After 12 proto types engine finally ready major thought name Super Cyclone would appropriate engines Tuner Save old I~giuOS f06Uc1 0 petSl~4G 9r .. spa PIU5to Over 600 items Send $200 current catalog made both 647 603 cu sizes arrived market early 1940 end year records 60-class engines held Super Cyclone 50000 sold first year World War II began model engine production ceased Mel got manufacturing job war effort war ended Mel told major would like go business himself ideas still better engine Moseley tried talk him staying making engine him Mel declined saying wanted own boss Two years designing setting up production resulted Ander son Spitfire Called engine reviewer Peter Chin Rolls-Royce spark ignition era engine also well ahead its time marvelous piece craftsmanship expensive make timer alone twice parts others engine priced twice cost other 60s market same time smaller displacement engines began gain popularity Anderson Spitfire financial success company soon trouble 1949 two men local news paper walked Mels shop wanted know engine could made inex pensively enough could given away new subscription promotion gimmick glow plug just arriving scene timer coil condenser batteries no longer re quired Mel believed could done set work 045 engine called Baby Spitfire Just development tooling completed paper changed its plans cancelled order Mel decided go ahead production sell through jobbers Mel using glow plug made K&B engines day called John Brodbeck K&B order 10000 plugs What guys doing down asked John ordered 17000 plugs last week Mel realized made mistake cat out bag number engines selling Mel decided begin making own plugs 156 Model Aviation OUR INVENTORY AVERAGES OVER 12000 PROPS! SPECIAL PRO SERIES PITCH BALSARI TE R/C WONDER JUICE Balsarite makes covering stick better also moisture-proofs wood adds little extra structural strength plus W prevents fuelcreep under seams LI fuelproofs engine compartments bALeLI attaches raw dacron k paper tissue CVERITE 420 Babylon Rd Horsham PA 19044 DIA 6 7 8 8* 9 10 10 11 11 11 * 12 13 14 15 16 DECIBAN SOUND LEVEL 95 5* 6NEW$209 10*6 6* 7NEW$239 11*7*8NEW$269 12 7* 8 NEW $299 FOUR-CYCLE TAILORED HELICAL PITCH ORDER BY MAIL OR PHONE 714 8305 162 fSORRY NO COD VISA & MASTERCARD WELCOME DEALER INOUIRIES INVITED ALL PRICES POSTPAID MINIMUM ORDER $1000 FOR INSURANCE ADD $100 ORDERS SHIPPED WITHIN 24 HRS CALIF RESIDENTS ADD 6% TAX