George Myers g behind deadline ever before struggling put results month experimenting 1500 words Bear something good may come out whole thing began several reader requests simple way evaluate servo know slow down lose torque get noisy interfere other system elec tronics get old tired some point repair replacement becomes necessary trick find point plane sitting workbench Most folks intuitively decide simple torque meter will solve problem look something can pressed down over servo airplane will detect servo about go over hill Ive built few dont job time servo weak enough torque meter show certainty performance down can see lost performance Besides dont want go twisting servo output arms servo resisting Its too easy damage gear teeth way speak experience am resisting temptation list bright ideas tested before settling simplest criteria test 1 The test shouldnt damage test article 2 The test results should specific defin ing good vs bad 3 The tools should readily available useable people have no interest elec tronics 4 The test should possible plane can conducted removing RC ind 4 4 d p q8V0L 10K p 7 I4 IJ p pp IMUO S IL 4 Figure 3 Before/after circuit diagrams portion Servo Cycle circuit affected modification almost meets old challenge Make work dont change anything can April 1980 17 RI New Figure 1 servo Strokes/Second Tester began life Ace R/C Inc Servo Cycle Circuit modifications slight few minutes shop time drill file adhesive label finish job arc adhesive label cut using fifty cent piece template WHAT servos feel weak slow project Im reporting month started out search simple answer complicated question Now find myself further 4 lOOK 4 4 1-igure 2 flese new parts used stallation 5 The test should simple perform 7 IC 9 AFTER solution perform transit time test purpose test determine transit time time seconds required servo move its output arm through specified angle has changed tools required test 1 An Ace RC Inc Servo Cycle mod fled measure transit time 2 A corner clipped off business card provide 900 reference set stroke servo 3 Your thumbnail 4 A stopwatch test procedure quite simple 1 Disconnect servo receiver plug Servo Cycle 2 Disconnect servo output wheel replace output arm 3 AdjustR5 shortpulseandR6 longpulse Servo Cycle circuit board produce total 9Q0 servo travel standard use regardless travel provided manufacturers transmitter 4 Set Servo Cycle its slowest rate turn 5 Place thumb ends out put arm tap nail alternately Keep thumb position See Figure 5 6 Set Servo Cycle its highest rate servo will unable follow rate arm will tap thumbnail 7 Slowly reduce cycling rate some point end arm will start tapping thumbnail Reduce rate some other end will also tap thumbnail Read transit time scale Servo Cycle 8 Turn everything off Compare reading just made reading made servo new transit time has increased 20% servo wants some maintenance point want know can get Servo Cycle modify product Ace R/C Inc Box 511 Higginsville MO 64037 listed kit 14G7 $1695 hobby dealer may have can order direct will also need 10000 ohm resistor 1 megohm potentiometer can pick off pegboard local Radio Shack order make connections battery pack servos obtain aileron extender cable suit RC system stop watch can scrounged friend necessary Now lets make tester Please build Servo Cycle according kit plans first get working properly will save answer ing lot letters blaming modification mining kits built other people After doing remove resistors Ri R2 circuit board Put new 10K resistor Ri used Put old Ri lOOK Brown Black Yellow R2 used leave long pigtail sticking up Next remove R4 5K potentiometer front panel Drill new between switches re-install R4 replaced Continued page 100 18 Model Aviation Figure 4 inside story plenty room servo Lycle case instaii mis mooiTicamion rigure 0 ne ueast action Georges thumbnail poised feel taps servo arm cycles past Count taps working stopwatch initial step set servo stroke angle adjusting Servo Cycles R5 R6 potentiometers George drilled holes side case make easy Zero Been hoarding Profile ship over year small-field free flight 049 High pyion sheet support well polyhedraled wing built-up lifting stab re mainder sheet Extremely simple frame minimum pieces beefyhigh performance man-trap arent going competition route Tight corkscrew climbwell need some simple mechanical stab pop-up fuse certainly Seelig timer Any suggestions feel bit witty resist going home again Letters Editor Continued page 8 power of15 less weights less 40 oz chase tail its chase lucky pass L F Randolph Dallas TX Unlike orherforms ofmodeling now part parcel everyday scene RC combat sofaran impromptu activity narrow interest may editorialize stepping too toes Fast RC combat sheer insanity horror menace everyone sight ofthe action have heard such ships shattering cloud chips after three flightsand should come after Randy describes may beand note maya fun way have Wyou must events infullscale modeling evolution has way turning butterflies monsters Hop up clip off etca thousand times no must live PC combat wed like frozen forever described letter editor hopes will never become formal event no can stop guys doing thing lets once exercise common sense opportunity remains expect some Dear Sir Cur letters So Merrill Hamburg Remembered page 96 December 1979 issue oi Model viation picture Merrill Hamburg friend would appreciate very much would give Mr Hamburgs address Back in1927Iguess Mr Hamburgpublished article merican Boy magazine build Baby ROG first experience model building believe little plane flew must have built dozen well other planes appeared later articles magazine As matter fact think Mr Hamburg real father model aviation As far am concerned no doubt Id like write Mr Hamburg send him some kind thoughts pleasure created addition Id like ask him would good enough autograph copy Beginning Fly wrote published Houghton Muffin Im still building flying RC days 50000th member AMA back 1974 Robert Lockwood Napa CA Mr Hamburg Hall Famer now deceasea guiding light behind old American Model League merica preceded 4MA about 10 years AMLA series Nationals late twenties early thirties before AMA appeared scene andfamous fliers like Wakefielder Gordon Lighl Max well Bassett first gassie ran away ru bberjobs late AMLA Nats competed 4merican Boy wonderful magazine victim Depression contained excellent plans solid scale models variety top rubberlobsand arrangement probably sparked Hamburg RC Technique/Myers Continued page 18 knob small wire nut make room See Figures 1 2 Finally install new 1 Meg potentiometer hole took R4 Depending pot obtained hole may have enlarged did Connect wire center terminal pot pigtail sticking up lOOK resistor Connect another wire R2 hole still open up eng lugs new pot modificaiton now complete will notice pictures Servo Cycle has pigtails several brands servos optional have also installed set nickel-cadmium pencells case remaining step calibration Plug servo get cycling new potenti ometer set middle its range Using stopwatch thumbnail count number taps 20 seconds calling first tap zero Calculate transit time follows 20 Seconds/Stroke Number taps 20 seconds Temporarily stick piece paper front panel put tick mark tip pointer mounted new petentiometer write transfer time Repeat necessary parts within normal tolerances scale should range 1 seconds 8 seconds per cycle covers practically servos use except very slow ones used retracting landing gears Inequalities between clockwise counter-clockwise strokes should always less 10% makes no difference side scale has short time have preference set up soldering wire 100 Model Aviation THE MODEL SAWMILL cut woods like Spruce White Ash Oak others useful modeling size Specify type build models order value assort ments Build better enjoy $11 opener sample modeler Tremendous small scales $33 xe bigger scales bigger selection bigger projects $55 r shelf builder really uses upPP Deliverysend Check MO Jim Scott Sawyer Ft Ashby W VA 26719 Chet Lanzo tail Maxwell Bassett No made laughs cheers Dallas AT LAST SOME Primer U ndercoeter Nowin Weve taken popular two-part white primer-undercoat formula made gray Just gray enough please have told us want see dents nicks ripples youre sanding Now make little visible just efficient ever course its still available white too Wood Plastic Metal Fiberglass Hobbypoxy primer-undercoater covers well cures fills fast shrinking easy sand provides smooth-as-glass surface. great adhesion wood plastic metal fiberglass Whether youre balsa builder molded plastic buff whether brush spray it. can now put little color life Hobbypoxy gray undercoat. good ever lot visible complete information how-to-do-it Hobbypoxy Finishing Guide write today ARNIIHAUIIvision Pettit Paint Co Inc H UDUIrUAT reooncis Street Rockaway NJ 07866 HOBBYPOXY ct group finishing products especially formulated hobbyists including Epoxy Glues Epoxy-enamel Paints Fillers Primer-undercoaters Resins R2 hole outside lug potentiometer opposite side want 1 seconds/stroke thing found testing servos column new servos arent necessarily fast advertised Some some arent what work theyre fast enough Log values find new look changes fact have changed information really want anyway Keep letters coming George M Myers 70 Froehlich Farm Rd Hicks yule NY 11801 About CG/Powers Continued page 22 I The engine thrust below CG will produce nose-up moment destabilizing tending move N forward 2 The propeller slip stream increases downwash over tail loading up pushing tail down nose up again destabilizing pushes N further ahead 3 The fatter fuselage presenting greater area upflow ahead wingmore instability N moves forward again 4 The fixed landing gear stabilizing tends pull nose down cancel effects other items some extent net result scale models similar basic configuration Neutral Point usually winds up very close 30% chord wing Thus good safe comfortable CG location about 5% forward 30% Neutral Point 25% chord So now understand CG forward beginners can further aft experts As matter fact have several models balanced approximately 25% tickles see little birds recover nicely stall generally forgiving mistakes controlling fliers dont seem pay much attention CG Location just balance airplane about third way back put seem fine because pretty good fliers would guess may struggling against some stability realizing way sure course test fly model varying CG locations Move CG forward little bit time until its hard get nose up can slow down landing move CG aft small increments until becomes sensitive skittish Ease back little both extremes let limits beginners CG location 25% chord good place start have expressing CG location percent chord because have used constant chord rectangular wing example airplanes made way course Some have tapered wings some have elliptical wings some have triangular wings some have two three wings what chord next installment will discuss Mean Aerodynamic Chord find configurations just mentioned Questions comments may addressed author care editor continued RC Aerobatics/Van Putte Continued page 23 thrust two propellers will deliver compar ing load factor props load factor determined multiplying prop pitch cube diameter example 1 1-8 prophas aloadfactorof8 X1 l 8 comparison 11 -7 prop has load factor 7 X1I53 6 According rule thrust developed 11-8 prop should about same 11 -7 prop know small engine will tum large prop So trick using load factor rule determine typical load factor range different engines vary prop characteristics get desired performance What follows table engine sizes versus load factor ranges flier should find displacement engine question read across load factor range engine table presented included article B J Rich Richburg Central Virginia Radio Control Association Virginia Newsletter Engine Displacement 05 10 15 20 25 30 35 40 45 50 60 80 Load Factor Range 400- 680 900- 1500 1500- 2500 2000- 3000 2600- 3650 3350- 4600 4000- 5500 4600- 6200 5200- 7000 6000- 8400 7600- 10800 9900-14000 flier should rate engine compared others same displacement new Schnuerle ported ringed piston engine will able swing higher load factor prop old boostported lapped piston engine ofthe same displace ment Pick out load factor corresponding April 1980 101 TTER FROM HOBBYPOXY
Edition: Model Aviation - 1980/04
Page Numbers: 17, 18, 100, 101
George Myers g behind deadline ever before struggling put results month experimenting 1500 words Bear something good may come out whole thing began several reader requests simple way evaluate servo know slow down lose torque get noisy interfere other system elec tronics get old tired some point repair replacement becomes necessary trick find point plane sitting workbench Most folks intuitively decide simple torque meter will solve problem look something can pressed down over servo airplane will detect servo about go over hill Ive built few dont job time servo weak enough torque meter show certainty performance down can see lost performance Besides dont want go twisting servo output arms servo resisting Its too easy damage gear teeth way speak experience am resisting temptation list bright ideas tested before settling simplest criteria test 1 The test shouldnt damage test article 2 The test results should specific defin ing good vs bad 3 The tools should readily available useable people have no interest elec tronics 4 The test should possible plane can conducted removing RC ind 4 4 d p q8V0L 10K p 7 I4 IJ p pp IMUO S IL 4 Figure 3 Before/after circuit diagrams portion Servo Cycle circuit affected modification almost meets old challenge Make work dont change anything can April 1980 17 RI New Figure 1 servo Strokes/Second Tester began life Ace R/C Inc Servo Cycle Circuit modifications slight few minutes shop time drill file adhesive label finish job arc adhesive label cut using fifty cent piece template WHAT servos feel weak slow project Im reporting month started out search simple answer complicated question Now find myself further 4 lOOK 4 4 1-igure 2 flese new parts used stallation 5 The test should simple perform 7 IC 9 AFTER solution perform transit time test purpose test determine transit time time seconds required servo move its output arm through specified angle has changed tools required test 1 An Ace RC Inc Servo Cycle mod fled measure transit time 2 A corner clipped off business card provide 900 reference set stroke servo 3 Your thumbnail 4 A stopwatch test procedure quite simple 1 Disconnect servo receiver plug Servo Cycle 2 Disconnect servo output wheel replace output arm 3 AdjustR5 shortpulseandR6 longpulse Servo Cycle circuit board produce total 9Q0 servo travel standard use regardless travel provided manufacturers transmitter 4 Set Servo Cycle its slowest rate turn 5 Place thumb ends out put arm tap nail alternately Keep thumb position See Figure 5 6 Set Servo Cycle its highest rate servo will unable follow rate arm will tap thumbnail 7 Slowly reduce cycling rate some point end arm will start tapping thumbnail Reduce rate some other end will also tap thumbnail Read transit time scale Servo Cycle 8 Turn everything off Compare reading just made reading made servo new transit time has increased 20% servo wants some maintenance point want know can get Servo Cycle modify product Ace R/C Inc Box 511 Higginsville MO 64037 listed kit 14G7 $1695 hobby dealer may have can order direct will also need 10000 ohm resistor 1 megohm potentiometer can pick off pegboard local Radio Shack order make connections battery pack servos obtain aileron extender cable suit RC system stop watch can scrounged friend necessary Now lets make tester Please build Servo Cycle according kit plans first get working properly will save answer ing lot letters blaming modification mining kits built other people After doing remove resistors Ri R2 circuit board Put new 10K resistor Ri used Put old Ri lOOK Brown Black Yellow R2 used leave long pigtail sticking up Next remove R4 5K potentiometer front panel Drill new between switches re-install R4 replaced Continued page 100 18 Model Aviation Figure 4 inside story plenty room servo Lycle case instaii mis mooiTicamion rigure 0 ne ueast action Georges thumbnail poised feel taps servo arm cycles past Count taps working stopwatch initial step set servo stroke angle adjusting Servo Cycles R5 R6 potentiometers George drilled holes side case make easy Zero Been hoarding Profile ship over year small-field free flight 049 High pyion sheet support well polyhedraled wing built-up lifting stab re mainder sheet Extremely simple frame minimum pieces beefyhigh performance man-trap arent going competition route Tight corkscrew climbwell need some simple mechanical stab pop-up fuse certainly Seelig timer Any suggestions feel bit witty resist going home again Letters Editor Continued page 8 power of15 less weights less 40 oz chase tail its chase lucky pass L F Randolph Dallas TX Unlike orherforms ofmodeling now part parcel everyday scene RC combat sofaran impromptu activity narrow interest may editorialize stepping too toes Fast RC combat sheer insanity horror menace everyone sight ofthe action have heard such ships shattering cloud chips after three flightsand should come after Randy describes may beand note maya fun way have Wyou must events infullscale modeling evolution has way turning butterflies monsters Hop up clip off etca thousand times no must live PC combat wed like frozen forever described letter editor hopes will never become formal event no can stop guys doing thing lets once exercise common sense opportunity remains expect some Dear Sir Cur letters So Merrill Hamburg Remembered page 96 December 1979 issue oi Model viation picture Merrill Hamburg friend would appreciate very much would give Mr Hamburgs address Back in1927Iguess Mr Hamburgpublished article merican Boy magazine build Baby ROG first experience model building believe little plane flew must have built dozen well other planes appeared later articles magazine As matter fact think Mr Hamburg real father model aviation As far am concerned no doubt Id like write Mr Hamburg send him some kind thoughts pleasure created addition Id like ask him would good enough autograph copy Beginning Fly wrote published Houghton Muffin Im still building flying RC days 50000th member AMA back 1974 Robert Lockwood Napa CA Mr Hamburg Hall Famer now deceasea guiding light behind old American Model League merica preceded 4MA about 10 years AMLA series Nationals late twenties early thirties before AMA appeared scene andfamous fliers like Wakefielder Gordon Lighl Max well Bassett first gassie ran away ru bberjobs late AMLA Nats competed 4merican Boy wonderful magazine victim Depression contained excellent plans solid scale models variety top rubberlobsand arrangement probably sparked Hamburg RC Technique/Myers Continued page 18 knob small wire nut make room See Figures 1 2 Finally install new 1 Meg potentiometer hole took R4 Depending pot obtained hole may have enlarged did Connect wire center terminal pot pigtail sticking up lOOK resistor Connect another wire R2 hole still open up eng lugs new pot modificaiton now complete will notice pictures Servo Cycle has pigtails several brands servos optional have also installed set nickel-cadmium pencells case remaining step calibration Plug servo get cycling new potenti ometer set middle its range Using stopwatch thumbnail count number taps 20 seconds calling first tap zero Calculate transit time follows 20 Seconds/Stroke Number taps 20 seconds Temporarily stick piece paper front panel put tick mark tip pointer mounted new petentiometer write transfer time Repeat necessary parts within normal tolerances scale should range 1 seconds 8 seconds per cycle covers practically servos use except very slow ones used retracting landing gears Inequalities between clockwise counter-clockwise strokes should always less 10% makes no difference side scale has short time have preference set up soldering wire 100 Model Aviation THE MODEL SAWMILL cut woods like Spruce White Ash Oak others useful modeling size Specify type build models order value assort ments Build better enjoy $11 opener sample modeler Tremendous small scales $33 xe bigger scales bigger selection bigger projects $55 r shelf builder really uses upPP Deliverysend Check MO Jim Scott Sawyer Ft Ashby W VA 26719 Chet Lanzo tail Maxwell Bassett No made laughs cheers Dallas AT LAST SOME Primer U ndercoeter Nowin Weve taken popular two-part white primer-undercoat formula made gray Just gray enough please have told us want see dents nicks ripples youre sanding Now make little visible just efficient ever course its still available white too Wood Plastic Metal Fiberglass Hobbypoxy primer-undercoater covers well cures fills fast shrinking easy sand provides smooth-as-glass surface. great adhesion wood plastic metal fiberglass Whether youre balsa builder molded plastic buff whether brush spray it. can now put little color life Hobbypoxy gray undercoat. good ever lot visible complete information how-to-do-it Hobbypoxy Finishing Guide write today ARNIIHAUIIvision Pettit Paint Co Inc H UDUIrUAT reooncis Street Rockaway NJ 07866 HOBBYPOXY ct group finishing products especially formulated hobbyists including Epoxy Glues Epoxy-enamel Paints Fillers Primer-undercoaters Resins R2 hole outside lug potentiometer opposite side want 1 seconds/stroke thing found testing servos column new servos arent necessarily fast advertised Some some arent what work theyre fast enough Log values find new look changes fact have changed information really want anyway Keep letters coming George M Myers 70 Froehlich Farm Rd Hicks yule NY 11801 About CG/Powers Continued page 22 I The engine thrust below CG will produce nose-up moment destabilizing tending move N forward 2 The propeller slip stream increases downwash over tail loading up pushing tail down nose up again destabilizing pushes N further ahead 3 The fatter fuselage presenting greater area upflow ahead wingmore instability N moves forward again 4 The fixed landing gear stabilizing tends pull nose down cancel effects other items some extent net result scale models similar basic configuration Neutral Point usually winds up very close 30% chord wing Thus good safe comfortable CG location about 5% forward 30% Neutral Point 25% chord So now understand CG forward beginners can further aft experts As matter fact have several models balanced approximately 25% tickles see little birds recover nicely stall generally forgiving mistakes controlling fliers dont seem pay much attention CG Location just balance airplane about third way back put seem fine because pretty good fliers would guess may struggling against some stability realizing way sure course test fly model varying CG locations Move CG forward little bit time until its hard get nose up can slow down landing move CG aft small increments until becomes sensitive skittish Ease back little both extremes let limits beginners CG location 25% chord good place start have expressing CG location percent chord because have used constant chord rectangular wing example airplanes made way course Some have tapered wings some have elliptical wings some have triangular wings some have two three wings what chord next installment will discuss Mean Aerodynamic Chord find configurations just mentioned Questions comments may addressed author care editor continued RC Aerobatics/Van Putte Continued page 23 thrust two propellers will deliver compar ing load factor props load factor determined multiplying prop pitch cube diameter example 1 1-8 prophas aloadfactorof8 X1 l 8 comparison 11 -7 prop has load factor 7 X1I53 6 According rule thrust developed 11-8 prop should about same 11 -7 prop know small engine will tum large prop So trick using load factor rule determine typical load factor range different engines vary prop characteristics get desired performance What follows table engine sizes versus load factor ranges flier should find displacement engine question read across load factor range engine table presented included article B J Rich Richburg Central Virginia Radio Control Association Virginia Newsletter Engine Displacement 05 10 15 20 25 30 35 40 45 50 60 80 Load Factor Range 400- 680 900- 1500 1500- 2500 2000- 3000 2600- 3650 3350- 4600 4000- 5500 4600- 6200 5200- 7000 6000- 8400 7600- 10800 9900-14000 flier should rate engine compared others same displacement new Schnuerle ported ringed piston engine will able swing higher load factor prop old boostported lapped piston engine ofthe same displace ment Pick out load factor corresponding April 1980 101 TTER FROM HOBBYPOXY
Edition: Model Aviation - 1980/04
Page Numbers: 17, 18, 100, 101
George Myers g behind deadline ever before struggling put results month experimenting 1500 words Bear something good may come out whole thing began several reader requests simple way evaluate servo know slow down lose torque get noisy interfere other system elec tronics get old tired some point repair replacement becomes necessary trick find point plane sitting workbench Most folks intuitively decide simple torque meter will solve problem look something can pressed down over servo airplane will detect servo about go over hill Ive built few dont job time servo weak enough torque meter show certainty performance down can see lost performance Besides dont want go twisting servo output arms servo resisting Its too easy damage gear teeth way speak experience am resisting temptation list bright ideas tested before settling simplest criteria test 1 The test shouldnt damage test article 2 The test results should specific defin ing good vs bad 3 The tools should readily available useable people have no interest elec tronics 4 The test should possible plane can conducted removing RC ind 4 4 d p q8V0L 10K p 7 I4 IJ p pp IMUO S IL 4 Figure 3 Before/after circuit diagrams portion Servo Cycle circuit affected modification almost meets old challenge Make work dont change anything can April 1980 17 RI New Figure 1 servo Strokes/Second Tester began life Ace R/C Inc Servo Cycle Circuit modifications slight few minutes shop time drill file adhesive label finish job arc adhesive label cut using fifty cent piece template WHAT servos feel weak slow project Im reporting month started out search simple answer complicated question Now find myself further 4 lOOK 4 4 1-igure 2 flese new parts used stallation 5 The test should simple perform 7 IC 9 AFTER solution perform transit time test purpose test determine transit time time seconds required servo move its output arm through specified angle has changed tools required test 1 An Ace RC Inc Servo Cycle mod fled measure transit time 2 A corner clipped off business card provide 900 reference set stroke servo 3 Your thumbnail 4 A stopwatch test procedure quite simple 1 Disconnect servo receiver plug Servo Cycle 2 Disconnect servo output wheel replace output arm 3 AdjustR5 shortpulseandR6 longpulse Servo Cycle circuit board produce total 9Q0 servo travel standard use regardless travel provided manufacturers transmitter 4 Set Servo Cycle its slowest rate turn 5 Place thumb ends out put arm tap nail alternately Keep thumb position See Figure 5 6 Set Servo Cycle its highest rate servo will unable follow rate arm will tap thumbnail 7 Slowly reduce cycling rate some point end arm will start tapping thumbnail Reduce rate some other end will also tap thumbnail Read transit time scale Servo Cycle 8 Turn everything off Compare reading just made reading made servo new transit time has increased 20% servo wants some maintenance point want know can get Servo Cycle modify product Ace R/C Inc Box 511 Higginsville MO 64037 listed kit 14G7 $1695 hobby dealer may have can order direct will also need 10000 ohm resistor 1 megohm potentiometer can pick off pegboard local Radio Shack order make connections battery pack servos obtain aileron extender cable suit RC system stop watch can scrounged friend necessary Now lets make tester Please build Servo Cycle according kit plans first get working properly will save answer ing lot letters blaming modification mining kits built other people After doing remove resistors Ri R2 circuit board Put new 10K resistor Ri used Put old Ri lOOK Brown Black Yellow R2 used leave long pigtail sticking up Next remove R4 5K potentiometer front panel Drill new between switches re-install R4 replaced Continued page 100 18 Model Aviation Figure 4 inside story plenty room servo Lycle case instaii mis mooiTicamion rigure 0 ne ueast action Georges thumbnail poised feel taps servo arm cycles past Count taps working stopwatch initial step set servo stroke angle adjusting Servo Cycles R5 R6 potentiometers George drilled holes side case make easy Zero Been hoarding Profile ship over year small-field free flight 049 High pyion sheet support well polyhedraled wing built-up lifting stab re mainder sheet Extremely simple frame minimum pieces beefyhigh performance man-trap arent going competition route Tight corkscrew climbwell need some simple mechanical stab pop-up fuse certainly Seelig timer Any suggestions feel bit witty resist going home again Letters Editor Continued page 8 power of15 less weights less 40 oz chase tail its chase lucky pass L F Randolph Dallas TX Unlike orherforms ofmodeling now part parcel everyday scene RC combat sofaran impromptu activity narrow interest may editorialize stepping too toes Fast RC combat sheer insanity horror menace everyone sight ofthe action have heard such ships shattering cloud chips after three flightsand should come after Randy describes may beand note maya fun way have Wyou must events infullscale modeling evolution has way turning butterflies monsters Hop up clip off etca thousand times no must live PC combat wed like frozen forever described letter editor hopes will never become formal event no can stop guys doing thing lets once exercise common sense opportunity remains expect some Dear Sir Cur letters So Merrill Hamburg Remembered page 96 December 1979 issue oi Model viation picture Merrill Hamburg friend would appreciate very much would give Mr Hamburgs address Back in1927Iguess Mr Hamburgpublished article merican Boy magazine build Baby ROG first experience model building believe little plane flew must have built dozen well other planes appeared later articles magazine As matter fact think Mr Hamburg real father model aviation As far am concerned no doubt Id like write Mr Hamburg send him some kind thoughts pleasure created addition Id like ask him would good enough autograph copy Beginning Fly wrote published Houghton Muffin Im still building flying RC days 50000th member AMA back 1974 Robert Lockwood Napa CA Mr Hamburg Hall Famer now deceasea guiding light behind old American Model League merica preceded 4MA about 10 years AMLA series Nationals late twenties early thirties before AMA appeared scene andfamous fliers like Wakefielder Gordon Lighl Max well Bassett first gassie ran away ru bberjobs late AMLA Nats competed 4merican Boy wonderful magazine victim Depression contained excellent plans solid scale models variety top rubberlobsand arrangement probably sparked Hamburg RC Technique/Myers Continued page 18 knob small wire nut make room See Figures 1 2 Finally install new 1 Meg potentiometer hole took R4 Depending pot obtained hole may have enlarged did Connect wire center terminal pot pigtail sticking up lOOK resistor Connect another wire R2 hole still open up eng lugs new pot modificaiton now complete will notice pictures Servo Cycle has pigtails several brands servos optional have also installed set nickel-cadmium pencells case remaining step calibration Plug servo get cycling new potenti ometer set middle its range Using stopwatch thumbnail count number taps 20 seconds calling first tap zero Calculate transit time follows 20 Seconds/Stroke Number taps 20 seconds Temporarily stick piece paper front panel put tick mark tip pointer mounted new petentiometer write transfer time Repeat necessary parts within normal tolerances scale should range 1 seconds 8 seconds per cycle covers practically servos use except very slow ones used retracting landing gears Inequalities between clockwise counter-clockwise strokes should always less 10% makes no difference side scale has short time have preference set up soldering wire 100 Model Aviation THE MODEL SAWMILL cut woods like Spruce White Ash Oak others useful modeling size Specify type build models order value assort ments Build better enjoy $11 opener sample modeler Tremendous small scales $33 xe bigger scales bigger selection bigger projects $55 r shelf builder really uses upPP Deliverysend Check MO Jim Scott Sawyer Ft Ashby W VA 26719 Chet Lanzo tail Maxwell Bassett No made laughs cheers Dallas AT LAST SOME Primer U ndercoeter Nowin Weve taken popular two-part white primer-undercoat formula made gray Just gray enough please have told us want see dents nicks ripples youre sanding Now make little visible just efficient ever course its still available white too Wood Plastic Metal Fiberglass Hobbypoxy primer-undercoater covers well cures fills fast shrinking easy sand provides smooth-as-glass surface. great adhesion wood plastic metal fiberglass Whether youre balsa builder molded plastic buff whether brush spray it. can now put little color life Hobbypoxy gray undercoat. good ever lot visible complete information how-to-do-it Hobbypoxy Finishing Guide write today ARNIIHAUIIvision Pettit Paint Co Inc H UDUIrUAT reooncis Street Rockaway NJ 07866 HOBBYPOXY ct group finishing products especially formulated hobbyists including Epoxy Glues Epoxy-enamel Paints Fillers Primer-undercoaters Resins R2 hole outside lug potentiometer opposite side want 1 seconds/stroke thing found testing servos column new servos arent necessarily fast advertised Some some arent what work theyre fast enough Log values find new look changes fact have changed information really want anyway Keep letters coming George M Myers 70 Froehlich Farm Rd Hicks yule NY 11801 About CG/Powers Continued page 22 I The engine thrust below CG will produce nose-up moment destabilizing tending move N forward 2 The propeller slip stream increases downwash over tail loading up pushing tail down nose up again destabilizing pushes N further ahead 3 The fatter fuselage presenting greater area upflow ahead wingmore instability N moves forward again 4 The fixed landing gear stabilizing tends pull nose down cancel effects other items some extent net result scale models similar basic configuration Neutral Point usually winds up very close 30% chord wing Thus good safe comfortable CG location about 5% forward 30% Neutral Point 25% chord So now understand CG forward beginners can further aft experts As matter fact have several models balanced approximately 25% tickles see little birds recover nicely stall generally forgiving mistakes controlling fliers dont seem pay much attention CG Location just balance airplane about third way back put seem fine because pretty good fliers would guess may struggling against some stability realizing way sure course test fly model varying CG locations Move CG forward little bit time until its hard get nose up can slow down landing move CG aft small increments until becomes sensitive skittish Ease back little both extremes let limits beginners CG location 25% chord good place start have expressing CG location percent chord because have used constant chord rectangular wing example airplanes made way course Some have tapered wings some have elliptical wings some have triangular wings some have two three wings what chord next installment will discuss Mean Aerodynamic Chord find configurations just mentioned Questions comments may addressed author care editor continued RC Aerobatics/Van Putte Continued page 23 thrust two propellers will deliver compar ing load factor props load factor determined multiplying prop pitch cube diameter example 1 1-8 prophas aloadfactorof8 X1 l 8 comparison 11 -7 prop has load factor 7 X1I53 6 According rule thrust developed 11-8 prop should about same 11 -7 prop know small engine will tum large prop So trick using load factor rule determine typical load factor range different engines vary prop characteristics get desired performance What follows table engine sizes versus load factor ranges flier should find displacement engine question read across load factor range engine table presented included article B J Rich Richburg Central Virginia Radio Control Association Virginia Newsletter Engine Displacement 05 10 15 20 25 30 35 40 45 50 60 80 Load Factor Range 400- 680 900- 1500 1500- 2500 2000- 3000 2600- 3650 3350- 4600 4000- 5500 4600- 6200 5200- 7000 6000- 8400 7600- 10800 9900-14000 flier should rate engine compared others same displacement new Schnuerle ported ringed piston engine will able swing higher load factor prop old boostported lapped piston engine ofthe same displace ment Pick out load factor corresponding April 1980 101 TTER FROM HOBBYPOXY
Edition: Model Aviation - 1980/04
Page Numbers: 17, 18, 100, 101
George Myers g behind deadline ever before struggling put results month experimenting 1500 words Bear something good may come out whole thing began several reader requests simple way evaluate servo know slow down lose torque get noisy interfere other system elec tronics get old tired some point repair replacement becomes necessary trick find point plane sitting workbench Most folks intuitively decide simple torque meter will solve problem look something can pressed down over servo airplane will detect servo about go over hill Ive built few dont job time servo weak enough torque meter show certainty performance down can see lost performance Besides dont want go twisting servo output arms servo resisting Its too easy damage gear teeth way speak experience am resisting temptation list bright ideas tested before settling simplest criteria test 1 The test shouldnt damage test article 2 The test results should specific defin ing good vs bad 3 The tools should readily available useable people have no interest elec tronics 4 The test should possible plane can conducted removing RC ind 4 4 d p q8V0L 10K p 7 I4 IJ p pp IMUO S IL 4 Figure 3 Before/after circuit diagrams portion Servo Cycle circuit affected modification almost meets old challenge Make work dont change anything can April 1980 17 RI New Figure 1 servo Strokes/Second Tester began life Ace R/C Inc Servo Cycle Circuit modifications slight few minutes shop time drill file adhesive label finish job arc adhesive label cut using fifty cent piece template WHAT servos feel weak slow project Im reporting month started out search simple answer complicated question Now find myself further 4 lOOK 4 4 1-igure 2 flese new parts used stallation 5 The test should simple perform 7 IC 9 AFTER solution perform transit time test purpose test determine transit time time seconds required servo move its output arm through specified angle has changed tools required test 1 An Ace RC Inc Servo Cycle mod fled measure transit time 2 A corner clipped off business card provide 900 reference set stroke servo 3 Your thumbnail 4 A stopwatch test procedure quite simple 1 Disconnect servo receiver plug Servo Cycle 2 Disconnect servo output wheel replace output arm 3 AdjustR5 shortpulseandR6 longpulse Servo Cycle circuit board produce total 9Q0 servo travel standard use regardless travel provided manufacturers transmitter 4 Set Servo Cycle its slowest rate turn 5 Place thumb ends out put arm tap nail alternately Keep thumb position See Figure 5 6 Set Servo Cycle its highest rate servo will unable follow rate arm will tap thumbnail 7 Slowly reduce cycling rate some point end arm will start tapping thumbnail Reduce rate some other end will also tap thumbnail Read transit time scale Servo Cycle 8 Turn everything off Compare reading just made reading made servo new transit time has increased 20% servo wants some maintenance point want know can get Servo Cycle modify product Ace R/C Inc Box 511 Higginsville MO 64037 listed kit 14G7 $1695 hobby dealer may have can order direct will also need 10000 ohm resistor 1 megohm potentiometer can pick off pegboard local Radio Shack order make connections battery pack servos obtain aileron extender cable suit RC system stop watch can scrounged friend necessary Now lets make tester Please build Servo Cycle according kit plans first get working properly will save answer ing lot letters blaming modification mining kits built other people After doing remove resistors Ri R2 circuit board Put new 10K resistor Ri used Put old Ri lOOK Brown Black Yellow R2 used leave long pigtail sticking up Next remove R4 5K potentiometer front panel Drill new between switches re-install R4 replaced Continued page 100 18 Model Aviation Figure 4 inside story plenty room servo Lycle case instaii mis mooiTicamion rigure 0 ne ueast action Georges thumbnail poised feel taps servo arm cycles past Count taps working stopwatch initial step set servo stroke angle adjusting Servo Cycles R5 R6 potentiometers George drilled holes side case make easy Zero Been hoarding Profile ship over year small-field free flight 049 High pyion sheet support well polyhedraled wing built-up lifting stab re mainder sheet Extremely simple frame minimum pieces beefyhigh performance man-trap arent going competition route Tight corkscrew climbwell need some simple mechanical stab pop-up fuse certainly Seelig timer Any suggestions feel bit witty resist going home again Letters Editor Continued page 8 power of15 less weights less 40 oz chase tail its chase lucky pass L F Randolph Dallas TX Unlike orherforms ofmodeling now part parcel everyday scene RC combat sofaran impromptu activity narrow interest may editorialize stepping too toes Fast RC combat sheer insanity horror menace everyone sight ofthe action have heard such ships shattering cloud chips after three flightsand should come after Randy describes may beand note maya fun way have Wyou must events infullscale modeling evolution has way turning butterflies monsters Hop up clip off etca thousand times no must live PC combat wed like frozen forever described letter editor hopes will never become formal event no can stop guys doing thing lets once exercise common sense opportunity remains expect some Dear Sir Cur letters So Merrill Hamburg Remembered page 96 December 1979 issue oi Model viation picture Merrill Hamburg friend would appreciate very much would give Mr Hamburgs address Back in1927Iguess Mr Hamburgpublished article merican Boy magazine build Baby ROG first experience model building believe little plane flew must have built dozen well other planes appeared later articles magazine As matter fact think Mr Hamburg real father model aviation As far am concerned no doubt Id like write Mr Hamburg send him some kind thoughts pleasure created addition Id like ask him would good enough autograph copy Beginning Fly wrote published Houghton Muffin Im still building flying RC days 50000th member AMA back 1974 Robert Lockwood Napa CA Mr Hamburg Hall Famer now deceasea guiding light behind old American Model League merica preceded 4MA about 10 years AMLA series Nationals late twenties early thirties before AMA appeared scene andfamous fliers like Wakefielder Gordon Lighl Max well Bassett first gassie ran away ru bberjobs late AMLA Nats competed 4merican Boy wonderful magazine victim Depression contained excellent plans solid scale models variety top rubberlobsand arrangement probably sparked Hamburg RC Technique/Myers Continued page 18 knob small wire nut make room See Figures 1 2 Finally install new 1 Meg potentiometer hole took R4 Depending pot obtained hole may have enlarged did Connect wire center terminal pot pigtail sticking up lOOK resistor Connect another wire R2 hole still open up eng lugs new pot modificaiton now complete will notice pictures Servo Cycle has pigtails several brands servos optional have also installed set nickel-cadmium pencells case remaining step calibration Plug servo get cycling new potenti ometer set middle its range Using stopwatch thumbnail count number taps 20 seconds calling first tap zero Calculate transit time follows 20 Seconds/Stroke Number taps 20 seconds Temporarily stick piece paper front panel put tick mark tip pointer mounted new petentiometer write transfer time Repeat necessary parts within normal tolerances scale should range 1 seconds 8 seconds per cycle covers practically servos use except very slow ones used retracting landing gears Inequalities between clockwise counter-clockwise strokes should always less 10% makes no difference side scale has short time have preference set up soldering wire 100 Model Aviation THE MODEL SAWMILL cut woods like Spruce White Ash Oak others useful modeling size Specify type build models order value assort ments Build better enjoy $11 opener sample modeler Tremendous small scales $33 xe bigger scales bigger selection bigger projects $55 r shelf builder really uses upPP Deliverysend Check MO Jim Scott Sawyer Ft Ashby W VA 26719 Chet Lanzo tail Maxwell Bassett No made laughs cheers Dallas AT LAST SOME Primer U ndercoeter Nowin Weve taken popular two-part white primer-undercoat formula made gray Just gray enough please have told us want see dents nicks ripples youre sanding Now make little visible just efficient ever course its still available white too Wood Plastic Metal Fiberglass Hobbypoxy primer-undercoater covers well cures fills fast shrinking easy sand provides smooth-as-glass surface. great adhesion wood plastic metal fiberglass Whether youre balsa builder molded plastic buff whether brush spray it. can now put little color life Hobbypoxy gray undercoat. good ever lot visible complete information how-to-do-it Hobbypoxy Finishing Guide write today ARNIIHAUIIvision Pettit Paint Co Inc H UDUIrUAT reooncis Street Rockaway NJ 07866 HOBBYPOXY ct group finishing products especially formulated hobbyists including Epoxy Glues Epoxy-enamel Paints Fillers Primer-undercoaters Resins R2 hole outside lug potentiometer opposite side want 1 seconds/stroke thing found testing servos column new servos arent necessarily fast advertised Some some arent what work theyre fast enough Log values find new look changes fact have changed information really want anyway Keep letters coming George M Myers 70 Froehlich Farm Rd Hicks yule NY 11801 About CG/Powers Continued page 22 I The engine thrust below CG will produce nose-up moment destabilizing tending move N forward 2 The propeller slip stream increases downwash over tail loading up pushing tail down nose up again destabilizing pushes N further ahead 3 The fatter fuselage presenting greater area upflow ahead wingmore instability N moves forward again 4 The fixed landing gear stabilizing tends pull nose down cancel effects other items some extent net result scale models similar basic configuration Neutral Point usually winds up very close 30% chord wing Thus good safe comfortable CG location about 5% forward 30% Neutral Point 25% chord So now understand CG forward beginners can further aft experts As matter fact have several models balanced approximately 25% tickles see little birds recover nicely stall generally forgiving mistakes controlling fliers dont seem pay much attention CG Location just balance airplane about third way back put seem fine because pretty good fliers would guess may struggling against some stability realizing way sure course test fly model varying CG locations Move CG forward little bit time until its hard get nose up can slow down landing move CG aft small increments until becomes sensitive skittish Ease back little both extremes let limits beginners CG location 25% chord good place start have expressing CG location percent chord because have used constant chord rectangular wing example airplanes made way course Some have tapered wings some have elliptical wings some have triangular wings some have two three wings what chord next installment will discuss Mean Aerodynamic Chord find configurations just mentioned Questions comments may addressed author care editor continued RC Aerobatics/Van Putte Continued page 23 thrust two propellers will deliver compar ing load factor props load factor determined multiplying prop pitch cube diameter example 1 1-8 prophas aloadfactorof8 X1 l 8 comparison 11 -7 prop has load factor 7 X1I53 6 According rule thrust developed 11-8 prop should about same 11 -7 prop know small engine will tum large prop So trick using load factor rule determine typical load factor range different engines vary prop characteristics get desired performance What follows table engine sizes versus load factor ranges flier should find displacement engine question read across load factor range engine table presented included article B J Rich Richburg Central Virginia Radio Control Association Virginia Newsletter Engine Displacement 05 10 15 20 25 30 35 40 45 50 60 80 Load Factor Range 400- 680 900- 1500 1500- 2500 2000- 3000 2600- 3650 3350- 4600 4000- 5500 4600- 6200 5200- 7000 6000- 8400 7600- 10800 9900-14000 flier should rate engine compared others same displacement new Schnuerle ported ringed piston engine will able swing higher load factor prop old boostported lapped piston engine ofthe same displace ment Pick out load factor corresponding April 1980 101 TTER FROM HOBBYPOXY