HERE IS Jetex-powered model devel oped especially Junior modelers easy build consistent flyer flown competition capable bring ing home trophy Hot Wood de signed 60s sons Tom flew first Hot Wood Dayton Wingmasters Club contest Jetex 50 powered models won model has flown twice AMA National Contest Jim placed third Junior Rocket 1969 Willow Grove Nationals out-of-sight flight Greg placed first Junior Rocket 1974 Lake Charles Nationals familiar Jetex flying know blown gaskets real prob lem use EN2 HT 50 Jetex engine loaded standard Jetex 50 fuel pellets Since double retaining springs HT 50 nozzle assembly engi neered handle very rapid burning HT 50 fuel have practically no blown gasket problems Give model try Construct out warps will have machine fun fly Hot Wood built young Greg Mills trophies won 1969 74 Nationals high thrust line eliminates power zooms El Il $ 1114 7Ati 997 Twice Nationals Winner sure-shot performer fun sport well competition James M Mills Construction Start wing Select sheet ghtweight C grain balsa free warps wing Mark outline wing balsa cut out Locate high point wing indicated plans draw line along top wing point Mark dihedral joint locations making sure square lead ing edge Using razor plane cut away material high point wing trailing edge straight line See airfoil section drawings Any wood left area excess weight model must light fly properly front airfoil should planed off carefully starting leading edge working back high point Note underside leading edge rounded off slightly careful take too much off top Taper wing tip dihedral joints tip using razor plane important keep tips light razor plane should used cut wing close final shape thickness sanding used obtain final finish familiar razor plane some suggestions old Gillette Blue blades far best blades use razor plane almost impossible find stainless steel other super blades work well however Gillette thin blades work reasonably well plane cut center wing towards tip always cut razor plane about 30- 45degree angle direction stroke Try cutting trailing edge wing first razor plane cutting too deeply can loosen blade shift back slightly Make sure blade squarely located plane Sometimes turning blade over will improve cut Dont press down hard razor plane use light long strokes After wing roughed shape razor plane sand wing good grade sandpaper important suggest #150-grade aluminum-oxide paper-wrapped around 2 4 k wood tacked top side sanding wing desired shape thickness very careful sanding close tips trailing edges especially sandpaper new cuts balsa very fast Finish sanding wing using 280- 320-grade paper block get smooth finish Cut stabilizer shape out 1/16 C-grain speckled stiff balsa Sand slight airfoil shape Again sand tips lighter sand area stabilizer mounts fuselage since would change angle incidence Cut rudder out 1/16 C-grain balsa sand shape rounding front edge sanding thinner toward top rear rudder Use sandpaper tail surfaces since surfaces December 1975 25 Hot Wood thin very little material re moved Brush coat sanding sealer doing both sides wing same time Make sure cover leading trailing tip edges Hold wing hand short until sealer starts set up place wing bottom side down across edges something flat such large metal can cooking dish similar item wing will stick lightly item used dries will keep wing warping Coat stabilizer rudder both sides using sanding sealer lay across top glass dry wing stabilizer rudder parts should dry overnight Sand wing using #320 paper apply coat low-shrink dope want durable finish repeat drying procedure parts drying go work fuselage Start straight length 1/8 /8 spruce Check carefully grain should run straight length body Flex spruce does snap back straight stays bent look another piece Lay out fuselage outline spruce measuring carefully height location shown leading edge wing rear fuselage Draw line between two points cut off excess carefully angle determines correct wing incidence Next cut off front fuselage angle shown Cut shape portion ahead wing forms engine mount pylon cut out 1/8 ce engine platform members Put plan flat building board cover waxed paper plastic like backing off Monokote Pin fuselage down over plan using slow drying epoxy glue engine pylon place Epoxy engine mount platforms place using square make sure lines up properly top fuselage Now sand rudder smooth using #320 sandpaper sand very lightly dont crack wood Glue rudder place fuselage pinned down flat rudder will off center fuselage rudder will abso lutely straight other After fuselage completely dry turn over epoxy other side engine mount platform place wing dry sand smooth using #320 sandpaper Carefully cut wing tip dihedral joints using X-Acto Razor Saw single-edge razor blade Hold wing down edge hardwood board very carefully sand enough angle get proper dihe dral Make sure good joints fit properly Note 1/16 sanded off rear portion tips give small amount washout Pin center section wing firmly building board glue tip dihedral first Block tips up required height block angled slightly main tain tip washout Put small weight top wing tip hold place cement dries Use either extra fast drying Ambroid Titebond joints first Later after joints set up good sand off bot tom side joint apply thin-skin coat Titebond epoxy over joints spread out stress strengthen joint tip joints completely dry cut center dihedral joint sand required angle get correct dihedral glueagain putting weight wing assure does raise up glue dries Mark fuselage wing stabilizer mounted Sand edges fuselage round except wing stabilizer located sand hard bend spruce fuselage out line Sanding corners round will make fuselage flexible well removing excess weight Sand out cuts nicks fuselage will tend break locations Glue wing fuselage make sure centerline wing located over center fuselage square used mark wing joints wing mounted square fuselage plane will have tendency turn toward whichever wing tip farthest back want type turn control wing should mounted fuselage level possi ble After wing securely glued place install stabilizer side higher other Seen rear plane will turn toward whichever tip stabilizer highest raise righthand stabilizer tip obtain righthand glide circle View plane front looking past wing toward stabilizer check stabilizer high side relation wings inboard section Make sure adjustments cor rect wing straight stabilizer has proper amount tilt joints 26 Model Aviation Layout model parts before shaping sanding Note engine pylon mounting platform parts cut fuselage material Note careful marking out very soft pencil assist accurate shaping design Jim Mills sons Tom Greg Heres dry flying surfaces doped avoid warps First coat sanding sealer place across flat dish dry Good air circulation allows parts dry evenly parts will stick lightly dish also helps prevent warping 18 7/8 WINGSPAN 4 7/16 Li A-A 1/8 C B-BC-CD-D FUSELAGE SECTIONS 121 5/8 L 61 1/2 5. LE HIGH POINT OF AIRFOIIi SAND 1/16 OFF TIP JOINT FOR TIP WASHOUT STABILIZER 1/16 LE C GRAIN SHEET 5. WING l/4 LIGHT STRAIGHT GRAIN OR C GRAIN BALSA OF WING TRIM TAB CUT INTO TRAILING EDGE BEND DOWN RIGHT WING TIP 1 /4 SECTION 6 5/8AT TIP OF WING LLB1/8x3/4 SPRUCE FUSELAGE FORMED WIRE SAFETY ANCHOR 14 1/8 STABILIZER LOCATIONJ ~1 TOP VIEW OF FUSELAGE 0123456 Inches St Jr Rocket 74 Nationals Jr Rocket 69 NatIonals HUI W~5J 3rd DesIgned & Drawn JIm Mills 0 4 -I 5/s. 3/4. CD 0 CD CD I CO s-J 0 N D Hot Wood dry apply additional skin coat Titebond epoxy over wing tail joints really fasten place Note epoxy Titebond type glues draw harden will change alignment took much care get just right Bend wire hook epoxy place front fuselage indi cated safety wire con nects engine plane should come loose flight crash Coat entire front engine pylon both sides thin coat epoxy point /8 behind leading edge wing strengthen area engine should mounted model balances point indicated plan Draw centerline en gine mount platform Screw engine mounting bracket place screw holes located directly over centerline Hand glide plane over grass check glide giving firm push straight out slightly downward upward glide may appear slightly nose heavy dont move engine unless glide quite nose heavy model will glide stalling glide should pretty good once find correct launch speed first flight should made using fuel pellet Make small block out hard wood put engine Cover asbestos gasket install single pellet Rough up sur face pellet coil up end fuse lay roughed-up area secure place screen furnished fuel cut extra large notch screens prevent screen touching fuse carefully thread through engine fuse opening careful crack fuse material passes through opening fuse should move freely back forth after engine assembled very careful fuse inserting engine mounting bracket first flights should made fairly calm day Make sure safety wire connected between engine plane use piece DT fuse light Jetex fuse works fine windy allows light fuse immediately whenever ready fuse will burn like small sparkler right up through hole may take just second ignite fuel pellet after burns through opening First will hiss slow down start steady hiss lot Junior modelers throw models minute first hiss starts since engine has built up power plane stalls dives ground As soon steady hiss starts launch plane straight out level flight just trying glide model continued page 79 28 Model Aviation Close-up engine mounting platform shows safety wire instal lation Purpose prevent loose engine flying off Aight Place blocking under tip hold correct height panels glued gether Set block angle provide tip-panel washout Hot Wood/Mills continued page 28 model should go straight out about 30 feet pick up speed go 30- 40degree climb model banks too steeply toward side cut small tab about 3/16 deep trailing edge wing low turn Bend tab down about 1/16 about thickness trailing edge tab will act aileron model picks up speed will hold up wing allowing model climb higher Whatever dont bend rudder correct flight path unless other adjustments fail job use very small amount rudder adjust ment models has flown right off building board very little final adjustment required models have equipped dethermalizer drop-weight-type similar type used hand-launched gliders will allow practice losing plane word caution about Jetex en gines very hot after flight dont pick up model engine until sure has cooled off B u bbleg un/Dunham continued page 36 balance construction consists sheet-metal forming wire bending used coat hanger wire easy bend removing paint soldered areas small tin can used soap reser voir ease soldering however alumi num will attachments will have epoxied can dipping wire assembled off blower epoxied place shown pop bottle cap liner removed 3/8 diameter hole drilled center cap sol dered wire dipper vertical position blowing position completed next step assemble blower 6-volt dry-cell battery 6 long piece yardstick tape though original defroster set up 12-volt operation 6-volt battery results better bubble formation slightly reducing fan speed air veloc ity use Lux liquid soap solution undiluted form possibly other soap solutions combinations might result improvement dip find steady stream bubbles will emitted about 3-4 seconds short span time 30-50 individual bubbles will wafted air have good pair lungs possible operate blow ing air inlet screen leaving battery disconnected method also serves good back-up case get meet find battery dead previous weeks outing have questions suggested improvements please let know cannot locate defroster area send $700 postage p 0 Box 7151 Tulsa OkIa 74105 December 1975 79 Greg Mills lighting fuse Jetex engine fore flight 1974 Nationals photos shot Jim Mills
Edition: Model Aviation - 1975/12
Page Numbers: 25, 26, 27, 28, 79
HERE IS Jetex-powered model devel oped especially Junior modelers easy build consistent flyer flown competition capable bring ing home trophy Hot Wood de signed 60s sons Tom flew first Hot Wood Dayton Wingmasters Club contest Jetex 50 powered models won model has flown twice AMA National Contest Jim placed third Junior Rocket 1969 Willow Grove Nationals out-of-sight flight Greg placed first Junior Rocket 1974 Lake Charles Nationals familiar Jetex flying know blown gaskets real prob lem use EN2 HT 50 Jetex engine loaded standard Jetex 50 fuel pellets Since double retaining springs HT 50 nozzle assembly engi neered handle very rapid burning HT 50 fuel have practically no blown gasket problems Give model try Construct out warps will have machine fun fly Hot Wood built young Greg Mills trophies won 1969 74 Nationals high thrust line eliminates power zooms El Il $ 1114 7Ati 997 Twice Nationals Winner sure-shot performer fun sport well competition James M Mills Construction Start wing Select sheet ghtweight C grain balsa free warps wing Mark outline wing balsa cut out Locate high point wing indicated plans draw line along top wing point Mark dihedral joint locations making sure square lead ing edge Using razor plane cut away material high point wing trailing edge straight line See airfoil section drawings Any wood left area excess weight model must light fly properly front airfoil should planed off carefully starting leading edge working back high point Note underside leading edge rounded off slightly careful take too much off top Taper wing tip dihedral joints tip using razor plane important keep tips light razor plane should used cut wing close final shape thickness sanding used obtain final finish familiar razor plane some suggestions old Gillette Blue blades far best blades use razor plane almost impossible find stainless steel other super blades work well however Gillette thin blades work reasonably well plane cut center wing towards tip always cut razor plane about 30- 45degree angle direction stroke Try cutting trailing edge wing first razor plane cutting too deeply can loosen blade shift back slightly Make sure blade squarely located plane Sometimes turning blade over will improve cut Dont press down hard razor plane use light long strokes After wing roughed shape razor plane sand wing good grade sandpaper important suggest #150-grade aluminum-oxide paper-wrapped around 2 4 k wood tacked top side sanding wing desired shape thickness very careful sanding close tips trailing edges especially sandpaper new cuts balsa very fast Finish sanding wing using 280- 320-grade paper block get smooth finish Cut stabilizer shape out 1/16 C-grain speckled stiff balsa Sand slight airfoil shape Again sand tips lighter sand area stabilizer mounts fuselage since would change angle incidence Cut rudder out 1/16 C-grain balsa sand shape rounding front edge sanding thinner toward top rear rudder Use sandpaper tail surfaces since surfaces December 1975 25 Hot Wood thin very little material re moved Brush coat sanding sealer doing both sides wing same time Make sure cover leading trailing tip edges Hold wing hand short until sealer starts set up place wing bottom side down across edges something flat such large metal can cooking dish similar item wing will stick lightly item used dries will keep wing warping Coat stabilizer rudder both sides using sanding sealer lay across top glass dry wing stabilizer rudder parts should dry overnight Sand wing using #320 paper apply coat low-shrink dope want durable finish repeat drying procedure parts drying go work fuselage Start straight length 1/8 /8 spruce Check carefully grain should run straight length body Flex spruce does snap back straight stays bent look another piece Lay out fuselage outline spruce measuring carefully height location shown leading edge wing rear fuselage Draw line between two points cut off excess carefully angle determines correct wing incidence Next cut off front fuselage angle shown Cut shape portion ahead wing forms engine mount pylon cut out 1/8 ce engine platform members Put plan flat building board cover waxed paper plastic like backing off Monokote Pin fuselage down over plan using slow drying epoxy glue engine pylon place Epoxy engine mount platforms place using square make sure lines up properly top fuselage Now sand rudder smooth using #320 sandpaper sand very lightly dont crack wood Glue rudder place fuselage pinned down flat rudder will off center fuselage rudder will abso lutely straight other After fuselage completely dry turn over epoxy other side engine mount platform place wing dry sand smooth using #320 sandpaper Carefully cut wing tip dihedral joints using X-Acto Razor Saw single-edge razor blade Hold wing down edge hardwood board very carefully sand enough angle get proper dihe dral Make sure good joints fit properly Note 1/16 sanded off rear portion tips give small amount washout Pin center section wing firmly building board glue tip dihedral first Block tips up required height block angled slightly main tain tip washout Put small weight top wing tip hold place cement dries Use either extra fast drying Ambroid Titebond joints first Later after joints set up good sand off bot tom side joint apply thin-skin coat Titebond epoxy over joints spread out stress strengthen joint tip joints completely dry cut center dihedral joint sand required angle get correct dihedral glueagain putting weight wing assure does raise up glue dries Mark fuselage wing stabilizer mounted Sand edges fuselage round except wing stabilizer located sand hard bend spruce fuselage out line Sanding corners round will make fuselage flexible well removing excess weight Sand out cuts nicks fuselage will tend break locations Glue wing fuselage make sure centerline wing located over center fuselage square used mark wing joints wing mounted square fuselage plane will have tendency turn toward whichever wing tip farthest back want type turn control wing should mounted fuselage level possi ble After wing securely glued place install stabilizer side higher other Seen rear plane will turn toward whichever tip stabilizer highest raise righthand stabilizer tip obtain righthand glide circle View plane front looking past wing toward stabilizer check stabilizer high side relation wings inboard section Make sure adjustments cor rect wing straight stabilizer has proper amount tilt joints 26 Model Aviation Layout model parts before shaping sanding Note engine pylon mounting platform parts cut fuselage material Note careful marking out very soft pencil assist accurate shaping design Jim Mills sons Tom Greg Heres dry flying surfaces doped avoid warps First coat sanding sealer place across flat dish dry Good air circulation allows parts dry evenly parts will stick lightly dish also helps prevent warping 18 7/8 WINGSPAN 4 7/16 Li A-A 1/8 C B-BC-CD-D FUSELAGE SECTIONS 121 5/8 L 61 1/2 5. LE HIGH POINT OF AIRFOIIi SAND 1/16 OFF TIP JOINT FOR TIP WASHOUT STABILIZER 1/16 LE C GRAIN SHEET 5. WING l/4 LIGHT STRAIGHT GRAIN OR C GRAIN BALSA OF WING TRIM TAB CUT INTO TRAILING EDGE BEND DOWN RIGHT WING TIP 1 /4 SECTION 6 5/8AT TIP OF WING LLB1/8x3/4 SPRUCE FUSELAGE FORMED WIRE SAFETY ANCHOR 14 1/8 STABILIZER LOCATIONJ ~1 TOP VIEW OF FUSELAGE 0123456 Inches St Jr Rocket 74 Nationals Jr Rocket 69 NatIonals HUI W~5J 3rd DesIgned & Drawn JIm Mills 0 4 -I 5/s. 3/4. CD 0 CD CD I CO s-J 0 N D Hot Wood dry apply additional skin coat Titebond epoxy over wing tail joints really fasten place Note epoxy Titebond type glues draw harden will change alignment took much care get just right Bend wire hook epoxy place front fuselage indi cated safety wire con nects engine plane should come loose flight crash Coat entire front engine pylon both sides thin coat epoxy point /8 behind leading edge wing strengthen area engine should mounted model balances point indicated plan Draw centerline en gine mount platform Screw engine mounting bracket place screw holes located directly over centerline Hand glide plane over grass check glide giving firm push straight out slightly downward upward glide may appear slightly nose heavy dont move engine unless glide quite nose heavy model will glide stalling glide should pretty good once find correct launch speed first flight should made using fuel pellet Make small block out hard wood put engine Cover asbestos gasket install single pellet Rough up sur face pellet coil up end fuse lay roughed-up area secure place screen furnished fuel cut extra large notch screens prevent screen touching fuse carefully thread through engine fuse opening careful crack fuse material passes through opening fuse should move freely back forth after engine assembled very careful fuse inserting engine mounting bracket first flights should made fairly calm day Make sure safety wire connected between engine plane use piece DT fuse light Jetex fuse works fine windy allows light fuse immediately whenever ready fuse will burn like small sparkler right up through hole may take just second ignite fuel pellet after burns through opening First will hiss slow down start steady hiss lot Junior modelers throw models minute first hiss starts since engine has built up power plane stalls dives ground As soon steady hiss starts launch plane straight out level flight just trying glide model continued page 79 28 Model Aviation Close-up engine mounting platform shows safety wire instal lation Purpose prevent loose engine flying off Aight Place blocking under tip hold correct height panels glued gether Set block angle provide tip-panel washout Hot Wood/Mills continued page 28 model should go straight out about 30 feet pick up speed go 30- 40degree climb model banks too steeply toward side cut small tab about 3/16 deep trailing edge wing low turn Bend tab down about 1/16 about thickness trailing edge tab will act aileron model picks up speed will hold up wing allowing model climb higher Whatever dont bend rudder correct flight path unless other adjustments fail job use very small amount rudder adjust ment models has flown right off building board very little final adjustment required models have equipped dethermalizer drop-weight-type similar type used hand-launched gliders will allow practice losing plane word caution about Jetex en gines very hot after flight dont pick up model engine until sure has cooled off B u bbleg un/Dunham continued page 36 balance construction consists sheet-metal forming wire bending used coat hanger wire easy bend removing paint soldered areas small tin can used soap reser voir ease soldering however alumi num will attachments will have epoxied can dipping wire assembled off blower epoxied place shown pop bottle cap liner removed 3/8 diameter hole drilled center cap sol dered wire dipper vertical position blowing position completed next step assemble blower 6-volt dry-cell battery 6 long piece yardstick tape though original defroster set up 12-volt operation 6-volt battery results better bubble formation slightly reducing fan speed air veloc ity use Lux liquid soap solution undiluted form possibly other soap solutions combinations might result improvement dip find steady stream bubbles will emitted about 3-4 seconds short span time 30-50 individual bubbles will wafted air have good pair lungs possible operate blow ing air inlet screen leaving battery disconnected method also serves good back-up case get meet find battery dead previous weeks outing have questions suggested improvements please let know cannot locate defroster area send $700 postage p 0 Box 7151 Tulsa OkIa 74105 December 1975 79 Greg Mills lighting fuse Jetex engine fore flight 1974 Nationals photos shot Jim Mills
Edition: Model Aviation - 1975/12
Page Numbers: 25, 26, 27, 28, 79
HERE IS Jetex-powered model devel oped especially Junior modelers easy build consistent flyer flown competition capable bring ing home trophy Hot Wood de signed 60s sons Tom flew first Hot Wood Dayton Wingmasters Club contest Jetex 50 powered models won model has flown twice AMA National Contest Jim placed third Junior Rocket 1969 Willow Grove Nationals out-of-sight flight Greg placed first Junior Rocket 1974 Lake Charles Nationals familiar Jetex flying know blown gaskets real prob lem use EN2 HT 50 Jetex engine loaded standard Jetex 50 fuel pellets Since double retaining springs HT 50 nozzle assembly engi neered handle very rapid burning HT 50 fuel have practically no blown gasket problems Give model try Construct out warps will have machine fun fly Hot Wood built young Greg Mills trophies won 1969 74 Nationals high thrust line eliminates power zooms El Il $ 1114 7Ati 997 Twice Nationals Winner sure-shot performer fun sport well competition James M Mills Construction Start wing Select sheet ghtweight C grain balsa free warps wing Mark outline wing balsa cut out Locate high point wing indicated plans draw line along top wing point Mark dihedral joint locations making sure square lead ing edge Using razor plane cut away material high point wing trailing edge straight line See airfoil section drawings Any wood left area excess weight model must light fly properly front airfoil should planed off carefully starting leading edge working back high point Note underside leading edge rounded off slightly careful take too much off top Taper wing tip dihedral joints tip using razor plane important keep tips light razor plane should used cut wing close final shape thickness sanding used obtain final finish familiar razor plane some suggestions old Gillette Blue blades far best blades use razor plane almost impossible find stainless steel other super blades work well however Gillette thin blades work reasonably well plane cut center wing towards tip always cut razor plane about 30- 45degree angle direction stroke Try cutting trailing edge wing first razor plane cutting too deeply can loosen blade shift back slightly Make sure blade squarely located plane Sometimes turning blade over will improve cut Dont press down hard razor plane use light long strokes After wing roughed shape razor plane sand wing good grade sandpaper important suggest #150-grade aluminum-oxide paper-wrapped around 2 4 k wood tacked top side sanding wing desired shape thickness very careful sanding close tips trailing edges especially sandpaper new cuts balsa very fast Finish sanding wing using 280- 320-grade paper block get smooth finish Cut stabilizer shape out 1/16 C-grain speckled stiff balsa Sand slight airfoil shape Again sand tips lighter sand area stabilizer mounts fuselage since would change angle incidence Cut rudder out 1/16 C-grain balsa sand shape rounding front edge sanding thinner toward top rear rudder Use sandpaper tail surfaces since surfaces December 1975 25 Hot Wood thin very little material re moved Brush coat sanding sealer doing both sides wing same time Make sure cover leading trailing tip edges Hold wing hand short until sealer starts set up place wing bottom side down across edges something flat such large metal can cooking dish similar item wing will stick lightly item used dries will keep wing warping Coat stabilizer rudder both sides using sanding sealer lay across top glass dry wing stabilizer rudder parts should dry overnight Sand wing using #320 paper apply coat low-shrink dope want durable finish repeat drying procedure parts drying go work fuselage Start straight length 1/8 /8 spruce Check carefully grain should run straight length body Flex spruce does snap back straight stays bent look another piece Lay out fuselage outline spruce measuring carefully height location shown leading edge wing rear fuselage Draw line between two points cut off excess carefully angle determines correct wing incidence Next cut off front fuselage angle shown Cut shape portion ahead wing forms engine mount pylon cut out 1/8 ce engine platform members Put plan flat building board cover waxed paper plastic like backing off Monokote Pin fuselage down over plan using slow drying epoxy glue engine pylon place Epoxy engine mount platforms place using square make sure lines up properly top fuselage Now sand rudder smooth using #320 sandpaper sand very lightly dont crack wood Glue rudder place fuselage pinned down flat rudder will off center fuselage rudder will abso lutely straight other After fuselage completely dry turn over epoxy other side engine mount platform place wing dry sand smooth using #320 sandpaper Carefully cut wing tip dihedral joints using X-Acto Razor Saw single-edge razor blade Hold wing down edge hardwood board very carefully sand enough angle get proper dihe dral Make sure good joints fit properly Note 1/16 sanded off rear portion tips give small amount washout Pin center section wing firmly building board glue tip dihedral first Block tips up required height block angled slightly main tain tip washout Put small weight top wing tip hold place cement dries Use either extra fast drying Ambroid Titebond joints first Later after joints set up good sand off bot tom side joint apply thin-skin coat Titebond epoxy over joints spread out stress strengthen joint tip joints completely dry cut center dihedral joint sand required angle get correct dihedral glueagain putting weight wing assure does raise up glue dries Mark fuselage wing stabilizer mounted Sand edges fuselage round except wing stabilizer located sand hard bend spruce fuselage out line Sanding corners round will make fuselage flexible well removing excess weight Sand out cuts nicks fuselage will tend break locations Glue wing fuselage make sure centerline wing located over center fuselage square used mark wing joints wing mounted square fuselage plane will have tendency turn toward whichever wing tip farthest back want type turn control wing should mounted fuselage level possi ble After wing securely glued place install stabilizer side higher other Seen rear plane will turn toward whichever tip stabilizer highest raise righthand stabilizer tip obtain righthand glide circle View plane front looking past wing toward stabilizer check stabilizer high side relation wings inboard section Make sure adjustments cor rect wing straight stabilizer has proper amount tilt joints 26 Model Aviation Layout model parts before shaping sanding Note engine pylon mounting platform parts cut fuselage material Note careful marking out very soft pencil assist accurate shaping design Jim Mills sons Tom Greg Heres dry flying surfaces doped avoid warps First coat sanding sealer place across flat dish dry Good air circulation allows parts dry evenly parts will stick lightly dish also helps prevent warping 18 7/8 WINGSPAN 4 7/16 Li A-A 1/8 C B-BC-CD-D FUSELAGE SECTIONS 121 5/8 L 61 1/2 5. LE HIGH POINT OF AIRFOIIi SAND 1/16 OFF TIP JOINT FOR TIP WASHOUT STABILIZER 1/16 LE C GRAIN SHEET 5. WING l/4 LIGHT STRAIGHT GRAIN OR C GRAIN BALSA OF WING TRIM TAB CUT INTO TRAILING EDGE BEND DOWN RIGHT WING TIP 1 /4 SECTION 6 5/8AT TIP OF WING LLB1/8x3/4 SPRUCE FUSELAGE FORMED WIRE SAFETY ANCHOR 14 1/8 STABILIZER LOCATIONJ ~1 TOP VIEW OF FUSELAGE 0123456 Inches St Jr Rocket 74 Nationals Jr Rocket 69 NatIonals HUI W~5J 3rd DesIgned & Drawn JIm Mills 0 4 -I 5/s. 3/4. CD 0 CD CD I CO s-J 0 N D Hot Wood dry apply additional skin coat Titebond epoxy over wing tail joints really fasten place Note epoxy Titebond type glues draw harden will change alignment took much care get just right Bend wire hook epoxy place front fuselage indi cated safety wire con nects engine plane should come loose flight crash Coat entire front engine pylon both sides thin coat epoxy point /8 behind leading edge wing strengthen area engine should mounted model balances point indicated plan Draw centerline en gine mount platform Screw engine mounting bracket place screw holes located directly over centerline Hand glide plane over grass check glide giving firm push straight out slightly downward upward glide may appear slightly nose heavy dont move engine unless glide quite nose heavy model will glide stalling glide should pretty good once find correct launch speed first flight should made using fuel pellet Make small block out hard wood put engine Cover asbestos gasket install single pellet Rough up sur face pellet coil up end fuse lay roughed-up area secure place screen furnished fuel cut extra large notch screens prevent screen touching fuse carefully thread through engine fuse opening careful crack fuse material passes through opening fuse should move freely back forth after engine assembled very careful fuse inserting engine mounting bracket first flights should made fairly calm day Make sure safety wire connected between engine plane use piece DT fuse light Jetex fuse works fine windy allows light fuse immediately whenever ready fuse will burn like small sparkler right up through hole may take just second ignite fuel pellet after burns through opening First will hiss slow down start steady hiss lot Junior modelers throw models minute first hiss starts since engine has built up power plane stalls dives ground As soon steady hiss starts launch plane straight out level flight just trying glide model continued page 79 28 Model Aviation Close-up engine mounting platform shows safety wire instal lation Purpose prevent loose engine flying off Aight Place blocking under tip hold correct height panels glued gether Set block angle provide tip-panel washout Hot Wood/Mills continued page 28 model should go straight out about 30 feet pick up speed go 30- 40degree climb model banks too steeply toward side cut small tab about 3/16 deep trailing edge wing low turn Bend tab down about 1/16 about thickness trailing edge tab will act aileron model picks up speed will hold up wing allowing model climb higher Whatever dont bend rudder correct flight path unless other adjustments fail job use very small amount rudder adjust ment models has flown right off building board very little final adjustment required models have equipped dethermalizer drop-weight-type similar type used hand-launched gliders will allow practice losing plane word caution about Jetex en gines very hot after flight dont pick up model engine until sure has cooled off B u bbleg un/Dunham continued page 36 balance construction consists sheet-metal forming wire bending used coat hanger wire easy bend removing paint soldered areas small tin can used soap reser voir ease soldering however alumi num will attachments will have epoxied can dipping wire assembled off blower epoxied place shown pop bottle cap liner removed 3/8 diameter hole drilled center cap sol dered wire dipper vertical position blowing position completed next step assemble blower 6-volt dry-cell battery 6 long piece yardstick tape though original defroster set up 12-volt operation 6-volt battery results better bubble formation slightly reducing fan speed air veloc ity use Lux liquid soap solution undiluted form possibly other soap solutions combinations might result improvement dip find steady stream bubbles will emitted about 3-4 seconds short span time 30-50 individual bubbles will wafted air have good pair lungs possible operate blow ing air inlet screen leaving battery disconnected method also serves good back-up case get meet find battery dead previous weeks outing have questions suggested improvements please let know cannot locate defroster area send $700 postage p 0 Box 7151 Tulsa OkIa 74105 December 1975 79 Greg Mills lighting fuse Jetex engine fore flight 1974 Nationals photos shot Jim Mills
Edition: Model Aviation - 1975/12
Page Numbers: 25, 26, 27, 28, 79
HERE IS Jetex-powered model devel oped especially Junior modelers easy build consistent flyer flown competition capable bring ing home trophy Hot Wood de signed 60s sons Tom flew first Hot Wood Dayton Wingmasters Club contest Jetex 50 powered models won model has flown twice AMA National Contest Jim placed third Junior Rocket 1969 Willow Grove Nationals out-of-sight flight Greg placed first Junior Rocket 1974 Lake Charles Nationals familiar Jetex flying know blown gaskets real prob lem use EN2 HT 50 Jetex engine loaded standard Jetex 50 fuel pellets Since double retaining springs HT 50 nozzle assembly engi neered handle very rapid burning HT 50 fuel have practically no blown gasket problems Give model try Construct out warps will have machine fun fly Hot Wood built young Greg Mills trophies won 1969 74 Nationals high thrust line eliminates power zooms El Il $ 1114 7Ati 997 Twice Nationals Winner sure-shot performer fun sport well competition James M Mills Construction Start wing Select sheet ghtweight C grain balsa free warps wing Mark outline wing balsa cut out Locate high point wing indicated plans draw line along top wing point Mark dihedral joint locations making sure square lead ing edge Using razor plane cut away material high point wing trailing edge straight line See airfoil section drawings Any wood left area excess weight model must light fly properly front airfoil should planed off carefully starting leading edge working back high point Note underside leading edge rounded off slightly careful take too much off top Taper wing tip dihedral joints tip using razor plane important keep tips light razor plane should used cut wing close final shape thickness sanding used obtain final finish familiar razor plane some suggestions old Gillette Blue blades far best blades use razor plane almost impossible find stainless steel other super blades work well however Gillette thin blades work reasonably well plane cut center wing towards tip always cut razor plane about 30- 45degree angle direction stroke Try cutting trailing edge wing first razor plane cutting too deeply can loosen blade shift back slightly Make sure blade squarely located plane Sometimes turning blade over will improve cut Dont press down hard razor plane use light long strokes After wing roughed shape razor plane sand wing good grade sandpaper important suggest #150-grade aluminum-oxide paper-wrapped around 2 4 k wood tacked top side sanding wing desired shape thickness very careful sanding close tips trailing edges especially sandpaper new cuts balsa very fast Finish sanding wing using 280- 320-grade paper block get smooth finish Cut stabilizer shape out 1/16 C-grain speckled stiff balsa Sand slight airfoil shape Again sand tips lighter sand area stabilizer mounts fuselage since would change angle incidence Cut rudder out 1/16 C-grain balsa sand shape rounding front edge sanding thinner toward top rear rudder Use sandpaper tail surfaces since surfaces December 1975 25 Hot Wood thin very little material re moved Brush coat sanding sealer doing both sides wing same time Make sure cover leading trailing tip edges Hold wing hand short until sealer starts set up place wing bottom side down across edges something flat such large metal can cooking dish similar item wing will stick lightly item used dries will keep wing warping Coat stabilizer rudder both sides using sanding sealer lay across top glass dry wing stabilizer rudder parts should dry overnight Sand wing using #320 paper apply coat low-shrink dope want durable finish repeat drying procedure parts drying go work fuselage Start straight length 1/8 /8 spruce Check carefully grain should run straight length body Flex spruce does snap back straight stays bent look another piece Lay out fuselage outline spruce measuring carefully height location shown leading edge wing rear fuselage Draw line between two points cut off excess carefully angle determines correct wing incidence Next cut off front fuselage angle shown Cut shape portion ahead wing forms engine mount pylon cut out 1/8 ce engine platform members Put plan flat building board cover waxed paper plastic like backing off Monokote Pin fuselage down over plan using slow drying epoxy glue engine pylon place Epoxy engine mount platforms place using square make sure lines up properly top fuselage Now sand rudder smooth using #320 sandpaper sand very lightly dont crack wood Glue rudder place fuselage pinned down flat rudder will off center fuselage rudder will abso lutely straight other After fuselage completely dry turn over epoxy other side engine mount platform place wing dry sand smooth using #320 sandpaper Carefully cut wing tip dihedral joints using X-Acto Razor Saw single-edge razor blade Hold wing down edge hardwood board very carefully sand enough angle get proper dihe dral Make sure good joints fit properly Note 1/16 sanded off rear portion tips give small amount washout Pin center section wing firmly building board glue tip dihedral first Block tips up required height block angled slightly main tain tip washout Put small weight top wing tip hold place cement dries Use either extra fast drying Ambroid Titebond joints first Later after joints set up good sand off bot tom side joint apply thin-skin coat Titebond epoxy over joints spread out stress strengthen joint tip joints completely dry cut center dihedral joint sand required angle get correct dihedral glueagain putting weight wing assure does raise up glue dries Mark fuselage wing stabilizer mounted Sand edges fuselage round except wing stabilizer located sand hard bend spruce fuselage out line Sanding corners round will make fuselage flexible well removing excess weight Sand out cuts nicks fuselage will tend break locations Glue wing fuselage make sure centerline wing located over center fuselage square used mark wing joints wing mounted square fuselage plane will have tendency turn toward whichever wing tip farthest back want type turn control wing should mounted fuselage level possi ble After wing securely glued place install stabilizer side higher other Seen rear plane will turn toward whichever tip stabilizer highest raise righthand stabilizer tip obtain righthand glide circle View plane front looking past wing toward stabilizer check stabilizer high side relation wings inboard section Make sure adjustments cor rect wing straight stabilizer has proper amount tilt joints 26 Model Aviation Layout model parts before shaping sanding Note engine pylon mounting platform parts cut fuselage material Note careful marking out very soft pencil assist accurate shaping design Jim Mills sons Tom Greg Heres dry flying surfaces doped avoid warps First coat sanding sealer place across flat dish dry Good air circulation allows parts dry evenly parts will stick lightly dish also helps prevent warping 18 7/8 WINGSPAN 4 7/16 Li A-A 1/8 C B-BC-CD-D FUSELAGE SECTIONS 121 5/8 L 61 1/2 5. LE HIGH POINT OF AIRFOIIi SAND 1/16 OFF TIP JOINT FOR TIP WASHOUT STABILIZER 1/16 LE C GRAIN SHEET 5. WING l/4 LIGHT STRAIGHT GRAIN OR C GRAIN BALSA OF WING TRIM TAB CUT INTO TRAILING EDGE BEND DOWN RIGHT WING TIP 1 /4 SECTION 6 5/8AT TIP OF WING LLB1/8x3/4 SPRUCE FUSELAGE FORMED WIRE SAFETY ANCHOR 14 1/8 STABILIZER LOCATIONJ ~1 TOP VIEW OF FUSELAGE 0123456 Inches St Jr Rocket 74 Nationals Jr Rocket 69 NatIonals HUI W~5J 3rd DesIgned & Drawn JIm Mills 0 4 -I 5/s. 3/4. CD 0 CD CD I CO s-J 0 N D Hot Wood dry apply additional skin coat Titebond epoxy over wing tail joints really fasten place Note epoxy Titebond type glues draw harden will change alignment took much care get just right Bend wire hook epoxy place front fuselage indi cated safety wire con nects engine plane should come loose flight crash Coat entire front engine pylon both sides thin coat epoxy point /8 behind leading edge wing strengthen area engine should mounted model balances point indicated plan Draw centerline en gine mount platform Screw engine mounting bracket place screw holes located directly over centerline Hand glide plane over grass check glide giving firm push straight out slightly downward upward glide may appear slightly nose heavy dont move engine unless glide quite nose heavy model will glide stalling glide should pretty good once find correct launch speed first flight should made using fuel pellet Make small block out hard wood put engine Cover asbestos gasket install single pellet Rough up sur face pellet coil up end fuse lay roughed-up area secure place screen furnished fuel cut extra large notch screens prevent screen touching fuse carefully thread through engine fuse opening careful crack fuse material passes through opening fuse should move freely back forth after engine assembled very careful fuse inserting engine mounting bracket first flights should made fairly calm day Make sure safety wire connected between engine plane use piece DT fuse light Jetex fuse works fine windy allows light fuse immediately whenever ready fuse will burn like small sparkler right up through hole may take just second ignite fuel pellet after burns through opening First will hiss slow down start steady hiss lot Junior modelers throw models minute first hiss starts since engine has built up power plane stalls dives ground As soon steady hiss starts launch plane straight out level flight just trying glide model continued page 79 28 Model Aviation Close-up engine mounting platform shows safety wire instal lation Purpose prevent loose engine flying off Aight Place blocking under tip hold correct height panels glued gether Set block angle provide tip-panel washout Hot Wood/Mills continued page 28 model should go straight out about 30 feet pick up speed go 30- 40degree climb model banks too steeply toward side cut small tab about 3/16 deep trailing edge wing low turn Bend tab down about 1/16 about thickness trailing edge tab will act aileron model picks up speed will hold up wing allowing model climb higher Whatever dont bend rudder correct flight path unless other adjustments fail job use very small amount rudder adjust ment models has flown right off building board very little final adjustment required models have equipped dethermalizer drop-weight-type similar type used hand-launched gliders will allow practice losing plane word caution about Jetex en gines very hot after flight dont pick up model engine until sure has cooled off B u bbleg un/Dunham continued page 36 balance construction consists sheet-metal forming wire bending used coat hanger wire easy bend removing paint soldered areas small tin can used soap reser voir ease soldering however alumi num will attachments will have epoxied can dipping wire assembled off blower epoxied place shown pop bottle cap liner removed 3/8 diameter hole drilled center cap sol dered wire dipper vertical position blowing position completed next step assemble blower 6-volt dry-cell battery 6 long piece yardstick tape though original defroster set up 12-volt operation 6-volt battery results better bubble formation slightly reducing fan speed air veloc ity use Lux liquid soap solution undiluted form possibly other soap solutions combinations might result improvement dip find steady stream bubbles will emitted about 3-4 seconds short span time 30-50 individual bubbles will wafted air have good pair lungs possible operate blow ing air inlet screen leaving battery disconnected method also serves good back-up case get meet find battery dead previous weeks outing have questions suggested improvements please let know cannot locate defroster area send $700 postage p 0 Box 7151 Tulsa OkIa 74105 December 1975 79 Greg Mills lighting fuse Jetex engine fore flight 1974 Nationals photos shot Jim Mills
Edition: Model Aviation - 1975/12
Page Numbers: 25, 26, 27, 28, 79
HERE IS Jetex-powered model devel oped especially Junior modelers easy build consistent flyer flown competition capable bring ing home trophy Hot Wood de signed 60s sons Tom flew first Hot Wood Dayton Wingmasters Club contest Jetex 50 powered models won model has flown twice AMA National Contest Jim placed third Junior Rocket 1969 Willow Grove Nationals out-of-sight flight Greg placed first Junior Rocket 1974 Lake Charles Nationals familiar Jetex flying know blown gaskets real prob lem use EN2 HT 50 Jetex engine loaded standard Jetex 50 fuel pellets Since double retaining springs HT 50 nozzle assembly engi neered handle very rapid burning HT 50 fuel have practically no blown gasket problems Give model try Construct out warps will have machine fun fly Hot Wood built young Greg Mills trophies won 1969 74 Nationals high thrust line eliminates power zooms El Il $ 1114 7Ati 997 Twice Nationals Winner sure-shot performer fun sport well competition James M Mills Construction Start wing Select sheet ghtweight C grain balsa free warps wing Mark outline wing balsa cut out Locate high point wing indicated plans draw line along top wing point Mark dihedral joint locations making sure square lead ing edge Using razor plane cut away material high point wing trailing edge straight line See airfoil section drawings Any wood left area excess weight model must light fly properly front airfoil should planed off carefully starting leading edge working back high point Note underside leading edge rounded off slightly careful take too much off top Taper wing tip dihedral joints tip using razor plane important keep tips light razor plane should used cut wing close final shape thickness sanding used obtain final finish familiar razor plane some suggestions old Gillette Blue blades far best blades use razor plane almost impossible find stainless steel other super blades work well however Gillette thin blades work reasonably well plane cut center wing towards tip always cut razor plane about 30- 45degree angle direction stroke Try cutting trailing edge wing first razor plane cutting too deeply can loosen blade shift back slightly Make sure blade squarely located plane Sometimes turning blade over will improve cut Dont press down hard razor plane use light long strokes After wing roughed shape razor plane sand wing good grade sandpaper important suggest #150-grade aluminum-oxide paper-wrapped around 2 4 k wood tacked top side sanding wing desired shape thickness very careful sanding close tips trailing edges especially sandpaper new cuts balsa very fast Finish sanding wing using 280- 320-grade paper block get smooth finish Cut stabilizer shape out 1/16 C-grain speckled stiff balsa Sand slight airfoil shape Again sand tips lighter sand area stabilizer mounts fuselage since would change angle incidence Cut rudder out 1/16 C-grain balsa sand shape rounding front edge sanding thinner toward top rear rudder Use sandpaper tail surfaces since surfaces December 1975 25 Hot Wood thin very little material re moved Brush coat sanding sealer doing both sides wing same time Make sure cover leading trailing tip edges Hold wing hand short until sealer starts set up place wing bottom side down across edges something flat such large metal can cooking dish similar item wing will stick lightly item used dries will keep wing warping Coat stabilizer rudder both sides using sanding sealer lay across top glass dry wing stabilizer rudder parts should dry overnight Sand wing using #320 paper apply coat low-shrink dope want durable finish repeat drying procedure parts drying go work fuselage Start straight length 1/8 /8 spruce Check carefully grain should run straight length body Flex spruce does snap back straight stays bent look another piece Lay out fuselage outline spruce measuring carefully height location shown leading edge wing rear fuselage Draw line between two points cut off excess carefully angle determines correct wing incidence Next cut off front fuselage angle shown Cut shape portion ahead wing forms engine mount pylon cut out 1/8 ce engine platform members Put plan flat building board cover waxed paper plastic like backing off Monokote Pin fuselage down over plan using slow drying epoxy glue engine pylon place Epoxy engine mount platforms place using square make sure lines up properly top fuselage Now sand rudder smooth using #320 sandpaper sand very lightly dont crack wood Glue rudder place fuselage pinned down flat rudder will off center fuselage rudder will abso lutely straight other After fuselage completely dry turn over epoxy other side engine mount platform place wing dry sand smooth using #320 sandpaper Carefully cut wing tip dihedral joints using X-Acto Razor Saw single-edge razor blade Hold wing down edge hardwood board very carefully sand enough angle get proper dihe dral Make sure good joints fit properly Note 1/16 sanded off rear portion tips give small amount washout Pin center section wing firmly building board glue tip dihedral first Block tips up required height block angled slightly main tain tip washout Put small weight top wing tip hold place cement dries Use either extra fast drying Ambroid Titebond joints first Later after joints set up good sand off bot tom side joint apply thin-skin coat Titebond epoxy over joints spread out stress strengthen joint tip joints completely dry cut center dihedral joint sand required angle get correct dihedral glueagain putting weight wing assure does raise up glue dries Mark fuselage wing stabilizer mounted Sand edges fuselage round except wing stabilizer located sand hard bend spruce fuselage out line Sanding corners round will make fuselage flexible well removing excess weight Sand out cuts nicks fuselage will tend break locations Glue wing fuselage make sure centerline wing located over center fuselage square used mark wing joints wing mounted square fuselage plane will have tendency turn toward whichever wing tip farthest back want type turn control wing should mounted fuselage level possi ble After wing securely glued place install stabilizer side higher other Seen rear plane will turn toward whichever tip stabilizer highest raise righthand stabilizer tip obtain righthand glide circle View plane front looking past wing toward stabilizer check stabilizer high side relation wings inboard section Make sure adjustments cor rect wing straight stabilizer has proper amount tilt joints 26 Model Aviation Layout model parts before shaping sanding Note engine pylon mounting platform parts cut fuselage material Note careful marking out very soft pencil assist accurate shaping design Jim Mills sons Tom Greg Heres dry flying surfaces doped avoid warps First coat sanding sealer place across flat dish dry Good air circulation allows parts dry evenly parts will stick lightly dish also helps prevent warping 18 7/8 WINGSPAN 4 7/16 Li A-A 1/8 C B-BC-CD-D FUSELAGE SECTIONS 121 5/8 L 61 1/2 5. LE HIGH POINT OF AIRFOIIi SAND 1/16 OFF TIP JOINT FOR TIP WASHOUT STABILIZER 1/16 LE C GRAIN SHEET 5. WING l/4 LIGHT STRAIGHT GRAIN OR C GRAIN BALSA OF WING TRIM TAB CUT INTO TRAILING EDGE BEND DOWN RIGHT WING TIP 1 /4 SECTION 6 5/8AT TIP OF WING LLB1/8x3/4 SPRUCE FUSELAGE FORMED WIRE SAFETY ANCHOR 14 1/8 STABILIZER LOCATIONJ ~1 TOP VIEW OF FUSELAGE 0123456 Inches St Jr Rocket 74 Nationals Jr Rocket 69 NatIonals HUI W~5J 3rd DesIgned & Drawn JIm Mills 0 4 -I 5/s. 3/4. CD 0 CD CD I CO s-J 0 N D Hot Wood dry apply additional skin coat Titebond epoxy over wing tail joints really fasten place Note epoxy Titebond type glues draw harden will change alignment took much care get just right Bend wire hook epoxy place front fuselage indi cated safety wire con nects engine plane should come loose flight crash Coat entire front engine pylon both sides thin coat epoxy point /8 behind leading edge wing strengthen area engine should mounted model balances point indicated plan Draw centerline en gine mount platform Screw engine mounting bracket place screw holes located directly over centerline Hand glide plane over grass check glide giving firm push straight out slightly downward upward glide may appear slightly nose heavy dont move engine unless glide quite nose heavy model will glide stalling glide should pretty good once find correct launch speed first flight should made using fuel pellet Make small block out hard wood put engine Cover asbestos gasket install single pellet Rough up sur face pellet coil up end fuse lay roughed-up area secure place screen furnished fuel cut extra large notch screens prevent screen touching fuse carefully thread through engine fuse opening careful crack fuse material passes through opening fuse should move freely back forth after engine assembled very careful fuse inserting engine mounting bracket first flights should made fairly calm day Make sure safety wire connected between engine plane use piece DT fuse light Jetex fuse works fine windy allows light fuse immediately whenever ready fuse will burn like small sparkler right up through hole may take just second ignite fuel pellet after burns through opening First will hiss slow down start steady hiss lot Junior modelers throw models minute first hiss starts since engine has built up power plane stalls dives ground As soon steady hiss starts launch plane straight out level flight just trying glide model continued page 79 28 Model Aviation Close-up engine mounting platform shows safety wire instal lation Purpose prevent loose engine flying off Aight Place blocking under tip hold correct height panels glued gether Set block angle provide tip-panel washout Hot Wood/Mills continued page 28 model should go straight out about 30 feet pick up speed go 30- 40degree climb model banks too steeply toward side cut small tab about 3/16 deep trailing edge wing low turn Bend tab down about 1/16 about thickness trailing edge tab will act aileron model picks up speed will hold up wing allowing model climb higher Whatever dont bend rudder correct flight path unless other adjustments fail job use very small amount rudder adjust ment models has flown right off building board very little final adjustment required models have equipped dethermalizer drop-weight-type similar type used hand-launched gliders will allow practice losing plane word caution about Jetex en gines very hot after flight dont pick up model engine until sure has cooled off B u bbleg un/Dunham continued page 36 balance construction consists sheet-metal forming wire bending used coat hanger wire easy bend removing paint soldered areas small tin can used soap reser voir ease soldering however alumi num will attachments will have epoxied can dipping wire assembled off blower epoxied place shown pop bottle cap liner removed 3/8 diameter hole drilled center cap sol dered wire dipper vertical position blowing position completed next step assemble blower 6-volt dry-cell battery 6 long piece yardstick tape though original defroster set up 12-volt operation 6-volt battery results better bubble formation slightly reducing fan speed air veloc ity use Lux liquid soap solution undiluted form possibly other soap solutions combinations might result improvement dip find steady stream bubbles will emitted about 3-4 seconds short span time 30-50 individual bubbles will wafted air have good pair lungs possible operate blow ing air inlet screen leaving battery disconnected method also serves good back-up case get meet find battery dead previous weeks outing have questions suggested improvements please let know cannot locate defroster area send $700 postage p 0 Box 7151 Tulsa OkIa 74105 December 1975 79 Greg Mills lighting fuse Jetex engine fore flight 1974 Nationals photos shot Jim Mills