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9. Thread a 4-40 nut onto a 4-40 x 4-1/2" [114mm]

pushrod. Make an L-bend in the non-threaded end of the
pushrod. Important: Put a drop or two of thread lock or
epoxy at the end of the threaded end of the pushrod.
Without the thread lock or epoxy the pushrod will vibrate
loose. Insert the pushrod through the slot in the sheeting
and screw the pushrod into one of the wheel collars. Make
sure the pushrod is tightened on the flat spot on the throttle
torque rod. Tighten the 4-40 nut against the wheel collar.
Make sure the pushrod and nut are tight.

10. Install the remaining two pushrods in the other two wheel

collars. The pushrods should be aligned with each other. If
the pushrods are not aligned, you may need to slightly
adjust the flat spots with a file.

11. Cut off the unthreaded portion of the pushrod. Thread

a nylon torque rod horn onto each pushrod so that the top
of the torque rod horn is flush with the end of the threads.

12. Use a bar sander to sand the top of the sub-leading

edges flush with the top of the ribs.

13. Position the wing back on its jigs. Use the two remaining

1/16" x 3" x 24" [1.6mm x 76mm x 610mm] balsa sheets to
sheet from the center of the main spar to the sub-leading
edge. Note: You may need to enlarge the slots for the
throttle torque rod horns so that they can be rotated up into
the wing to allow the wing to set on the jigs.

14. Mark the center of the landing gear torque block on

the landing gear rail. Drill a 5/32" [4mm] hole through both the
landing gear rail and torque block, perpendicular to the rail.

16

Summary of Contents for Profile 38

Page 1: ... product By the act of using the user assembled product the user accepts all resulting liability If the buyer is not prepared to accept the liability associated with the use of this product the buyer is advised to return this kit immediately in new and unused condition to the place of purchase READ THROUGH THIS MANUAL BEFORE STARTING CONSTRUCTION IT CONTAINS IMPORTANT INSTRUCTIONS AND WARNINGS CON...

Page 2: ...43 AMA SAFETY CODE excerpt 44 CHECK LIST 44 FLYING 45 Engine Setup 45 Takeoff 45 Flight 45 What To Do If One Engine Quits 45 Landing 46 TWO VIEW DRAWING Back Cover Page FUSE WING PLANS Center Pull Out Section Along with the P 51 the P 38 is one of the most admired planes of WW2 It is also one of the most difficult to build and fly But the Great Planes Profile 38 has eliminated those hurdles The bo...

Page 3: ...ress or telephone number below If you are contacting us for replacement parts please be sure to provide the full kit name Profile 38 and the part numbers as listed in the Parts List Great Planes Product Support 3002 N Apollo Drive Suite 1 Champaign IL 61822 Telephone 217 398 8970 Fax 217 398 7721 E mail productsupport greatplanes com You can also check our web site at www greatplanes com for the l...

Page 4: ...aling iron COVR2700 Top Flite Hot Sock iron cover TOPR2175 or 21st Century iron cover COVR2702 Top Flite MonoKote trim seal iron TOPR2200 or 21st Century trim seal iron COVR2750 Top Flite MonoKote heat gun TOPR2000 Here is a list of optional tools mentioned in the manual that will help you build the Profile 38 Pro Aliphatic resin 2 oz 60g GPMR6160 2 oz 57g Spray CA activator GPMR6035 4 oz 113g Aer...

Page 5: ...itional strength Photos and sketches are placed before the step they refer to Frequently you can study photos in following steps to get another view of the same parts Fuse Fuselage Stab Horizontal Stabilizer Fin Vertical Fin LE Leading Edge TE Trailing Edge LG Landing Gear Ply Plywood Inches mm Millimeters SHCS Socket Head Cap Screw COMMON ABBREVIATIONS IMPORTANT BUILDING NOTES EASY TOUCH BAR SAND...

Page 6: ...the die cut parts are difficult to punch out do not force them Instead cut around the parts with a hobby knife After punching out the die cut parts use your Bar Sander or sanding block to lightly sand the edges to remove any die cutting irregularities or slivers GET READY TO BUILD TYPES OF WOOD 6 0 1 2 3 4 5 6 7 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 Inch Scale Metric Sca...

Page 7: ...7 DIE CUT DRAWINGS ...

Page 8: ...trailing edge 5 Locate the four die cut 1 8 3mm balsa S3 stabilizer tips Make two sets of S3 s by gluing two of the 1 8 3mm S3 s together to make 1 4 6mm thick S3 s 6 Glue the S3 stabilizer tips to the trailing edge of the stabilizer 7 Locate the four die cut 1 8 3mm balsa S1 and S2 stabilizer tips Glue two of the S1 s together and two of the S2 s together to make two 1 4 6mm thick S1 s and S2 s 8...

Page 9: ...ge and elevator ends 4 Remove the elevator from your building board Inspect all the glue joints and add CA to any joints that don t look strong Fill any gaps with balsa sanding dust and a drop or two of thin CA First sand both sides of the stab and elevator flat and even Then round the edges of the stab and elevator as shown on the plan 1 Locate the four die cut 1 8 3mm balsa R1 rudder trailing ed...

Page 10: ...and build the second rudder Start by building the left wing panel upside down over the left wing panel plan so your progress matches the photos 1 Match the four 1 8 x 1 4 x 24 3mm x 6mm x 610mm basswood main spars so any warps will counteract each other 2 Cover the wing panel plan with waxed paper or Great Planes Plan Protector 3 Glue two of the die cut 3 ply W 3 ribs together 4 Glue the die cut 3...

Page 11: ...ther Use a straightedge to keep the two pieces aligned From the root rib insert the shear web through the center of the ribs Carefully rotate it so that the T on the shear web is towards your building board and the notches are aligned with the ribs Position the shear web so that it is as far back in the rib as possible The shear web will be centered on the main spar Pay special attention at ribs 1...

Page 12: ... ribs by 1 16 1 6mm and is flush with the side of rib W 3 Before the epoxy hardens wipe off any excess from rib W 2 using a paper towel dampened with denatured alcohol 1 From one of the 1 16 x 3 x 30 1 6mm x 76mm x 762mm balsa sheets cut a 1 16 x 5 8 x 30 1 6mm x 16mm x 762mm trailing edge strip Glue the strip to the sub trailing edge ribs W 1 through W 7 and the wing tip 2 True one edge of a 1 16...

Page 13: ...ust be securely glued to the main spar 5 Trim the sheeting flush with rib W 1 and the sub leading edge 6 Use epoxy to glue the 3 4 x 3 4 x 3 4 19mm x 19mm x 19mm hardwood landing gear torque block to the landing gear rail and rib W 2 7 Return to step 2 and build the right wing panel 1 Use epoxy to glue the two die cut 1 16 1 6mm plywood wing joiners together aligning the joiners at the center Befo...

Page 14: ...sub leading edge joiner in the front of the W 1 ribs and the sub leading edge 5 Use a planer and bar sander to trim the sub trailing edge flush with the top of the ribs Taper the tip of the sub trailing edge so that the trailing edge strip can be glued to the wing tip 6 Use a bar sander to taper the trailing edge sheeting to match the taper on ribs W 1 through W 3 See the wing cross section on the...

Page 15: ...e throttle torque rod through the wing ribs and position the wheel collars and plastic bearings on the rod 6 Use epoxy to glue the die cut 3 ply W 1A and W 3A sub ribs to both sides of the W 1 and W 3 ribs Also glue the throttle torque rod bearings to the ribs Be careful to not get epoxy in the plastic bearings A light coat of grease on the torque rod will prevent the epoxy from sticking to the to...

Page 16: ...he pushrods are not aligned you may need to slightly adjust the flat spots with a file 11 Cut off the unthreaded portion of the pushrod Thread a nylon torque rod horn onto each pushrod so that the top of the torque rod horn is flush with the end of the threads 12 Use a bar sander to sand the top of the sub leading edges flush with the top of the ribs 13 Position the wing back on its jigs Use the t...

Page 17: ...evious wing center sheeting 18 From the 1 16 x 1 4 x 24 1 6mm x 6mm x 610mm balsa stick cut and glue cap strips to the top of ribs W 4 through W 7 19 Glue the die cut 3 ply aileron servo trays and aileron tray supports to ribs W 3 and the bottom of the main spar 20 Glue the die cut 3 32 2mm balsa sub ribs W 1B to each side of the W 1 rib over the notch 21 From the 1 16 x 3 x 30 1 6mm x 76mm x 762m...

Page 18: ...e two 1 4 x 3 4 x 24 6mm x 19mm x 610mm balsa leading edges to the front of the sub leading edge 27 Using a razor plane and bar sander round the leading edge to match the wing cross section 28 Trim the top sheeting from over the two alignment slots in ribs W 1 The first slot is approximately 1 25mm from the leading edge and the second one is approximately 5 127mm from the leading edge A T pin work...

Page 19: ... We will install the ailerons after we fit the two booms on the wing 1 Cover the boom plan with wax paper or Great Planes Plan Protector 2 Glue two of the die cut 3 ply boom main frames 1 together Make sure the edges are aligned 3 Glue two of the die cut 3 ply elevator and rudder servo trays together 4 Glue two of the die cut 1 8 3mm balsa fin frame F1 F2 and F3 together to make 1 4 6mm thick part...

Page 20: ... 1 4 x 24 3mm x 6mm x 610mm balsa sticks cut and glue diagonal boom braces and fin ribs to the boom frame 9 Glue two of the die cut 1 8 3mm balsa aft fins F4 together Glue the aft fin to the trailing edge of the fin Note the direction of the wood grain 10 Remove the boom from your building board and return to step 2 and build the second boom 1 Remove the boom from your building board Use a bar san...

Page 21: ... 76mm x 762mm balsa sheet finish sheeting the bottom of the boom Trim the sheet around the outside of the boom 7 Using a sharp hobby knife trim the sheeting from inside the engine mount area the servo tray and the stabilizer saddle 8 Trim the wing saddle as shown Note that the sides are straight with the sheeting overhanging the boom Also trim the sheeting from over the two mounting tabs 9 Repeat ...

Page 22: ...ble the second upper boom 1 Mark one of the main booms left and the other right it doesn t matter which 2 Decide what size engines you are going to use We have provided die cut mounts for the O S 15 LA and the 25 LA If you are using a different engine you may need to trim the mounts to fit your engine The 15 size mounts have a 15 embossed on them and the 25 size mounts have a 25 embossed on them B...

Page 23: ... main boom flat on your building table Position the engine gauge at the front of the engine mount Raise the forward edge of the engine mount until it is aligned with the embossed line on the gauge You may need to lightly sand the engine mount to allow it to be rotated in the main boom 10 Use leftover 1 16 1 6mm balsa sheet to fill in behind the engine mount Sand the sheeting flush with the main bo...

Page 24: ... permanently attached to the wing INSTALL THE ENGINES B Using the bevel to lines and the centerline as a guide make the V on the leading edge of the rudder with a razor plane or the Great Planes Multi Sander GPMR6190 with 150 grit sandpaper How To Bevel The Leading Edge A Place the leading edge of the rudder on your work surface and use your pen to mark a bevel to line on both sides about 3 32 2mm...

Page 25: ... the engine mount and then through the engine mounting lugs Temporarily secure the engine to the mount with a 4 lock washer and 4 40 nut Install the other three screws washers and nuts 6 Return to step 1 and install the second engine on the left boom 7 Once both engines have been mounted remove them and proceed to attaching the booms to the wing 1 Sand a small radius along the top and bottom edges...

Page 26: ...zer joiner Make sure the main booms are perpendicular to your building table Check the measurements between the booms before the epoxy hardens Use a paper towel dampened with denatured alcohol to wipe off any excess epoxy before it hardens 8 Use balsa filler to fill any open joints between the main boom the wing and the upper boom Once the balsa filler has dried sand the upper boom so that it is f...

Page 27: ...ut 3 ply canopy frame 4 aligning the edges of the frames and the two center holes 2 Glue the four die cut 1 16 1 6mm plywood canopy alignment disks on each side of the alignment tabs on the canopy frame 3 Drill 1 16 1 6mm pilot holes at the punch marks in the die cut 3 ply formers F1 F2A and F2B 4 Glue former F2A to the canopy frame so it is perpendicular to the frame 5 Glue the die cut 3 ply serv...

Page 28: ...canopy frame on the top of the wing If the alignment tabs are too tight in the slots you can lightly sand the tabs The frame should contact the top of the wing and the aft edge of the servo tray should contact the leading edge Once satisfied with the fit use epoxy to glue the canopy frame and servo tray to the wing Make sure the canopy frame is straight 10 Glue the die cut 3 ply former F3 perpendi...

Page 29: ...Trim the bottom canopy so that the edge of the bottom and top canopy are flush Take off a little at a time A bar sander with 220 grit sandpaper works great for this 5 Mark the location of former F1 F2 on the lip of the top canopy Mark the bottom canopy 3 8 10mm aft of the former 6 Cut the nose from the bottom canopy at these marks Wrap a piece of tape around the canopy from mark to mark to act as ...

Page 30: ...ecessary The aft end of the bottom canopy should align with the trailing edge of the wing From scrap ABS make four 1 2 x 1 2 13mm x 13mm square canopy bottom tabs Glue the tabs to the forward edge of the bottom canopy They should overhang the edge by 1 4 6mm 11 Check fit the bottom canopy on the top canopy and wing Mounting blocks will be installed after the wing is covered to hold the canopy bott...

Page 31: ...e the screws and put a drop of thin CA in each hole to harden the wood After the CA has hardened reinstall the control horn with the screws 6 Center the aileron servo arm and mark where the pushrod crosses the arm Make a 90 bend at the mark cut the pushrod and attach it to the servo arm with a Faslink 7 Return to step 1 Install the Aileron Servos and install the other aileron servo 1 Using the har...

Page 32: ... the holes easily Once you have the outside radiator housing installed it will be difficult to view the hole 8 Return to step 1 and install the rudder servo in the right main boom 1 Position a large control horn on the elevator as shown on the plan Mark the location of the control horn mounting holes and drill 3 32 2 4mm holes at the marks Temporarily mount the elevator control horn on the elevato...

Page 33: ...t of the way and use a T pin to make sure no braces are under the sheeting If you find a brace under the sheeting move the guide slightly toward the stabilizer and check again 7 Use a sharp hobby knife to cut a hole in the inner main boom sheeting for the pushrod guide Depending on the bend in the pushrod you may need to shorten the guide Do not glue the guide in the main boom until after the plan...

Page 34: ... silicone clevis retainer over the clevis Attach the clevis to the torque rod horn at the center of the wing 4 Temporarily install both engines using only two screws to hold the engines in position The throttle linkage needs to be installed at this time to check that the slots are large enough before the wing is covered 5 Thread a nylon clevis approximately 14 full turns onto the threaded ends of ...

Page 35: ...into the top nose gear bearing The coil on the nose gear should be approximately 1 4 6mm from the bottom canopy 6 Rotate the nose gear so the axle is perpendicular to the centerline of the wing Offset the steering arm 3 or 4 degrees towards the steering servo and mark the location of the steering arm on the nose gear Remove the nose gear and file a flat at the steering arm location Reinstall the n...

Page 36: ...We suggest covering the larger areas first such as the wing and stabilizer center sections Then use the smaller leftover pieces of film to finish the stabilizer and wing tips and the fin and boom The black and white invasion stripes on the wing can be applied using several different methods The first method is to cover the wing completely with aluminum MonoKote film Then the white and blacks strip...

Page 37: ...ousing and trim the covering from inside the outline Use epoxy to attach the housings to the main booms Use a paper towel dampened with denatured alcohol to wipe off any excess epoxy before it hardens 4 For the two radiator housings that are on the inside of the main booms trim an opening on one end to allow the rudder and elevator pushrods to exit Installing Painting the Radiators Painting Your M...

Page 38: ...d are easy to apply 1 Cut the covering from the hinge slots in the elevator and stabilizer 2 Reinstall the CA hinges in the elevator without glue B If you used a Slot Machine to make the hinge slots this step is not necessary Otherwise drill a 3 32 2 4mm hole 1 2 12 7mm deep in the center of each hinge slot A high speed Dremel Tool works best for this If you use a regular drill clean the hinge slo...

Page 39: ... wheel collar on the nose gear axle Secure the wheel collars to the axle with 6 32 set screws and threadlocker Note We recommend that flat spots be filed on the axles to tighten the set screw on 3 Insert the main landing gear in the landing gear rails Position two nylon landing gear straps over the main landing gear as shown on the plan Mark the screw hole locations on the landing gear rail 4 Dril...

Page 40: ... the fuel tank to the carburetor and the pressure tap on the muffler 6 Return to step 3 and install the second fuel tank 1 Fit the top canopy on the canopy frame Mark the outline of the canopy on the wing To help the glue adhere to the wing use a T pin to poke small holes through the covering just inside the outline If you prefer to remove a strip of covering in the outline do not use a hobby knif...

Page 41: ...7 On our models we routed the receiver antenna out the back of the bottom canopy We also put the receiver on off switch and charge jack in the bottom canopy 1 Turn on the transmitter and receiver and center the trims If necessary remove the servo arms from the servos and reposition them so they are centered Reinstall the screws that hold on the servo arms 2 With the transmitter and receiver still ...

Page 42: ...f the lead weight to permanently hold it in place Over time fuel and exhaust residue may soften the adhesive and cause the weight to fall off Use 2 sheet metal screws RTV silicone or epoxy to permanently hold the weight in place 4 IMPORTANT If you found it necessary to add any weight recheck the C G after the weight has been installed This is where your model should balance for the first flights L...

Page 43: ... Profile 38 is a twin engine plane it is important that both engines operate the same Both engines should accelerate the same and have the same top RPM After you run the engines on the model inspect the model closely to make sure all screws remained tight the hinges pushrod and connectors are secure and the props have not come loose You should always check the operational range of your radio befor...

Page 44: ...irst flight of a new or repaired model 2 I will not fly my model aircraft in the presence of spectators until I become a qualified flier unless assisted by an experienced helper 3 I will perform my initial turn after takeoff away from the pit or spectator areas and I will not thereafter fly over pit or spectator areas unless beyond my control 4 I will operate my model using only radio control freq...

Page 45: ...el to establish a gentle climb to a safe altitude before turning into the traffic pattern For reassurance and to keep an eye on other traffic it is a good idea to have an assistant on the flight line with you Tell him to remind you to throttle back once the plane gets to a comfortable altitude While full throttle is usually desirable for takeoff most models fly more smoothly at reduced speeds Take...

Page 46: ... a loop check your altitude mind the wind direction anticipating rudder corrections that will be required to maintain heading remember to throttle back at the top and make certain you are on the desired rates high low rates A flight plan greatly reduces the chances of crashing your model just because of poor planning and impulsive moves Remember to think Have a ball But always stay in control and ...

Page 47: ..._______________ Where Purchased _________________________ Date Construction Started __________________ Date Construction Finished _________________ Finished Weight __________________________ Date of First Flight ________________________ FLIGHT LOG ...

Page 48: ...TWO VIEW DRAWING Use copies of this page to plan your trim scheme ...

Page 49: ...C B ...

Page 50: ...D A ...

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