KADET LT-25 RC74 WING CONSTRUCTION

The KADET LT-25ís wing is designed to be built in two halves - called the LEFT WING PANEL and the RIGHT WING PANEL as shown on fullsize plan sheet 2. Each wing panel will be built directly on top of its own plan, using the plan as a pattern to position the parts.

Itís best to work on just one wing panel at a time. Occasionally you will find as you are working on one wing panel that the parts you have already installed will be covering up some of the plan lines and text that you are looking for in a subsequent step. In that case, simply refer to the other wing panel plan to see what is covered up.

Letís start building the LEFT WING PANEL first.

1.

Cut the drawing of the LEFT WING PANEL loose from the rest of Plan Sheet 2. Tape or pin it on top of your building board. Cover the plan with a sheet of waxed. paper, also taped down. This will keep excess glue from sticking to the plan when you are gluing the parts in place.

2.

Locate one 3/16"x3/8"x36" balsa stick for the Bottom Main Wing Spar. Pin the Bottom Main Wing Spar in position on the plan.
IMPORTANT: Position the Bottom Main Spar on the plan precisely by lining up the outboard end of the spar flush with the location of the last W-5 wing rib. (at the wing tip).




3.

Use a razor saw to cut off the excess at the root rib (W-1.)

4.

Cut a piece of wing center sheet from the 3/32"x4"x24" balsa Sheet, to fit between the main and rear spars. Place on the plan, gluing and pining its front edge to the back of the Bottom Main Spar at the same time.

5.

Locate the 3/16"x1/4"x36" balsa stick for use as the Bottom Rear Spar and pin it in place on the plan, gluing it to the rear edge of the balsa sheet at the same time. Cut off the excess at the root rib (W-1).

6.

Cut a piece of wing trailing edge sheet from the 3/32"x3"x24" balsa sheet, to fit between the rear bottom spar and the trailing edge. Place on the plan gluing and pining its front edge to the back of the Bottom Rear Spar at the same time.




7.

Pin the pre-shaped balsa Trailing Edge in place on the plan, gluing it to the back edge of the trailing edge sheet at the same time. Be sure to align all of the notches in the Trailing Edge with the rib locations on the plan.

NOTE: It is possible for plan paper to shrink or expand slightly with humidity changes. If it has, this is where you will notice it! You may find that the rib notches in the Trailing Edge do not exactly match the rib locations on the plan. Nonetheless, they should be very close, not off by more than the thickness of a rib. A slight difference is nothing to worry about! The machine-cut notches in the Trailing Edge are correct, and you should build your wing according to them. To install a wing rib in the steps coming up, simply put the rear end of the rib in the notch, and then align the rest of the rib parallel with the rib lines on the plan. Do not alter the notches in the Trailing Edges!

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8. Carefully remove all the ribs (W-1 through W-5) from the lasercut sheets #1 through #5. Take time to familiarize yourself with the ribs and how they differ. You will notice that ribs W-1, W-2, W-3, and the front of rib W-4 are smaller than the W-5 ribs to all allow for the 3/32" thick balsa wing sheet pieces.

9.

Assemble (but donít glue) Wing Ribs W-2 thru W-5, plus the Main Spar Web and the Rear Spar Web, onto the Bottom Main Spar and Bottom Rear Spar. Do not glue any of these parts at this time!
Next add the Diagonal Wing Braces between the ribs as shown. Do not glue these either!.

NOTICE: The Diagonal Wing Braces ARE NOT SYMMETRICAL! Make sure you properly identify the top of each Brace


10.

Use the dihedral gauge to set the root rib (W-1) at the proper angle (3į). Glue the root rib to the bottom spars, balsa sheeting and trailing edge.


11.

Double check to see all the remaining ribs are 90į to the building board, if so glue all remaining Ribs, Spar Webs, and Diagonal Braces at all joints.

12.

Glue the pre-shaped balsa Leading Edge in place in the notches in the front of the wing ribs. Note that the Leading Edge is extra long! Glue it on with one end flush with the W-1 rib, and allow the other end to stick out past the last W-5 rib. Do not cut off the excess length at this time - we will do that later, after the wing tip is installed.
CAUTION: Take a close look at the end of the Leading Edge before gluing it in place! Notice that it is not symmetrical! Hold the Leading Edge against one of the wing cross-section drawing on Plan sheet 2, and after you are sure that you have it matched up correctly, mark an "up" arrow on one end. Now make sure you glue it into the wing right side up!

13.

With a X-Acto saw, finish cutting the notch in the W-1 and W-2 wing ribs using the laser-cut notches as a guide. This will leave a space for the dihedral brace.

14.

Glue the Top Main Spar and the Top Rear Spar in place. It is critical that you get a good glue joint between the spars and the spar webs, both top and bottom. Also, be sure to use the Dihedral Gauge to hold the W-1 wing rib at the correct angle when gluing the top spars in that area.
NOTE:
The top spars are extra long, just like the Leading Edge was. Like before, put one end of the spars flush with rib W-1, and leave the excess length at the tip end of the wing panel. They will be cut off later, after the wing tip is installed.




15.

Cut a piece of 3/32"x3" sheet balsa to fit between the Top Rear Spar and the Trailing Edge. Trim and sand the sheet carefully to fit and then glue it in place on the ribs. Next cut another piece of 3/32"x3" sheet balsa to fit between the Top Main Spar and the Leading Edge. Sand it to fit and then glue it in place. Last, cut more 3/32" sheet balsa to fit in the area between the Top Main Spar and the Top Rear Spar, and then glue it in place.
Caution: Be sure to remove any pins that are holding the wing structure to the building board in the areas where the top sheeting is going to be glued on. If you donít, youíll find it difficult to remove the wing from the building board later.

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16. After the glue on the center section sheets has cured, cut two 1/8" wide x1/2" long slots in the Top Leading Edge sheet at the W-4 wing rib to accomodate the ends of the two 1/8"x3/16"x24" balsa Top Forward Spars. Glue the Forward Spars into these slots and into the notcheds in the top of all the other wing ribs. Cut the Forward Spars off flush with the W-5 rib at the tip.
When all the glue joints have dried, unpin the wing panel from the building board and check it for straightness. If it looks straight, go back and reglue every joint in the wing panel using MEDIUM or THICK CA. Don't be stingy here - the integrity of your wing depends upon strong glue joints. Glue BOTH sides of EVERY joint! BE ABSOLUTELY POSITIVE THE SPAR WEBS ARE BONDED TO BOTH THE TOP AND BOTTOM SPARS

17.

Now you can add the wing tip! The only way to get the lasercut balsa wig tip in place is to slide it over the ends of the Top Spars, Leading Edge, and Trailing Edge - all at the same time. Itís a little tedious, but with a bit of careful wiggling and pushing, you should be able to get it to slide on OK. Once in position, securely glue the wing tip to all the parts it comes in contact with.

NOTE: Practically everywhere that the wing tip comes in contact with another part there are angles involved. This means there will be some unavoidable small gaps between the parts. For instance, underneath both of the Top Spars there will be a gap. Also around the backside of the Leading Edge there will be some gaps. All of these gaps can be filled with glue and light-weight wood filler.

18.

Cut the Leading Edge, Trailing Edge, Top Main Spar, and Top Rear Spar off flush with the bottom surface of the wing tip.

NOTE: Itís best to first make a "pretty close" cut with a razor saw to quickly remove the bulk of the part, and then use a sanding block to get everything perfectly flat and flush.




19.

Cut and fit 3/32"x3" balsa sheeting to fit between the Bottom Main Spar and the Leading Edge (just like in Step 15).

After the glue has dried, cut 1/8" wide x 1/2" long slots in the Top Leading Edge sheet at the W-4 wing rib to accomodate the ends of the two 1/8"x3/16"x24" balsa Top Forward Spars. Glue the Forward Spars into these slots and into the notcheds in the top of all the other wing ribs. Cut the Forward Spars off flush with the W-5 rib at the tip (see photo).







20.

Carefully saw off and block sand the root ends of all the Spars, Leading Edge, and Trailing Edge flush with the pre-angled W-1 wing rib. Use a large sanding block and sand slowly to keep the end of the wing panel straight and true. Try not to sand into the W-1 wing rib.

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21. Look closely at rib W-1 and youíll see that a cutout for the aileron servo has been partially pre-cut in the rib - itís a large inverted "U" shape, located aft of the main spars. Also notice that the vertical legs of the cutout stop short of the bottom of the rib. In this step, you will complete the aileron servo cutout in the W-1 rib. First lay the wing panel flat on the building board and use a modeling knife to cut straight down through the last of the rib on both vertical legs. Stop cutting when you get to the bottom wing sheet. Carefully break out the portion of the rib inside the cutout area.

Now repeat Steps 1 through 21 to build the other wing panel.


Joining The Wing Panels

22.

Trial fit the two wing panels with the 1/8" laser-cut plywood dihedral brace installed between the main spars. Be certain that the dihedral brace is not preventing the panels from making solid contact with each other at the center. If necessary, trim or sand the brace for a snug fit. The 3į dihedral per wing panel will automatically be built-in by the dihedral brace. If you want to check the angle, place the wing on the table so that one side sits flat, and the other is raised. The bottom of the raised wing tip should be about 3" above the surface of the table. A variation of up to 1/4" either way is acceptable and will not affect flight performance. The most important point to have a tight joint at the wing center with no gaps.

23.

Use epoxy (either SIG 5-MINUTE or SLOW-CURE) to join the two wing panels. Apply glue generously to the end ribs and the dihedral brace. Work some glue into the slot in each wing root. Carefully slide the wing halves into place and hold in place with pins and tape. Wipe away any excess epoxy that oozes from the center joint with a paper towel or a rag dampened with isopropyl alcohol. Before the glue cures, make sure that the leading and trailing edges of both panels are perfectly aligned and that there is no built-in twist. Let cure.



Aileron Installation

24.

Locate the two pre-shaped balsa Center Section Trailing Edge pieces. Mark one Left Bottom and one Right Bottom.

25.

On the Left Bottom Center Section Trailing Edge piece, draw a box 1/4" wide x 1/2" deep, exactly 7/16" from the end, as shown here. Continue the lines down the front of the piece, until you reach the bottom of the pre-cut groove in the front.




26.

Using a razor saw, carefully cut along the side lines of the box, stopping when the blade is deep enough to reach across to both end lines.



27.

Use a modeling knife to "chip" the wood out between the saw cuts until you have notch the full depth of the box you drew originally.

Repeat steps 25 through 27 to make the Right Bottom Center Section Trailing Edge a mirror image of the left one.

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28. Familiarize yourself with the pre-bent Aileron Torque Rods w/Brass Bearings. Note that there is a Left and a Right Torque Rod. Study their positions on the full size plans to help you identify which one is Left and which is Right. Notice that when the Torque Rods are in position in the wing, the threaded end of the Torque Rod will come out the bottom of the wing and the shorter unthreaded end will face back into the aileron.
Also notice that the threaded portions of the Torque Rods should lean back slightly towards the rear of the airplane when the ailerons are in neutral position. That rearward lean provides the Kadet LT-25 with a small amount of "differential" movement in the ailerons (more up than down), which makes for smoother turning.






29.

Use a small amount of Thick CA to glue the Brass Bearing portion of the Left Aileron Torque Rod into the groove in the front of the Left Center Section Trailing Edge piece. GLUE ONLY THE BRASS BEARING, NOT THE WIRE PORTION OF THE TORQUE ROD! The wire portion of the Torque Rod must be completely free to rotate inside the Brass Bearing. Now glue the Right Aileron Torque Rod into the groove in the front of the Right Center Section Trailing Edge.
IMPORTANT: Be sure to keep all glue at least 1/8" away from the ends of the Brass Bearings to minimize any chance of glue seeping inside the bearing and causing a bind in the movement of the Torque Rod.

30.

Apply a bead of Slow CA to the leading edges of the Left Center Section Trailing Edge piece. Keep the glue on the balsa, do not get any glue on the Torque Rod or the Brass Bearing! Hold the Center Section Trailing Edge assembly in position on the trailing edge of the wing. Use a straight edge to confirm that the bottom surface of the part is flush with the bottom surface of the wing. Let dry.

Repeat this step for the Right Center Section Trailing Edge piece on the back of the wing, also gluing it to the Left Center Trailing Edge at the same time. When the glue has cured, check to verify that both Aileron Toque Rods will pivot freely. If they donít, you must find the problem and correct it now before proceeding!

31.

Locate the two pre-shaped balsa wood Ailerons. Using a 3/32" dia. drill bit, drill a hole 5/8" deep in one end of each aileron to accept the Aileron Torque Rod wire. The location of the hole must be centered on the Leading edge of the aileron, and it should be 1-3/8" from the end of the aileron. The path of the hole must travel straight into the core of the aileron, centered equal distance from both sides.

32.

Use a modeling knife to cut a (3/32" wide x 3/32" deep) groove in the leading edge of the aileron to accept the Aileron Torque Rod wire. The groove should go from the 3/32" hole to the root end of the aileron. Trial fit the aileron over the end of the Torque Rod wire to check the fit.

33.

Tape the aileron into neutral position, with the root end in perfect alignment with the fixed Center Section Trailing Edge pieces.

34.

Pin a piece of scrap balsa to the bottom surfaces of both the aileron and the wing, out near the wing tip, to hold this end of the aileron securely in neutral position.



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35. Cut and block sand the end of the aileron to match the shape of the wing tip. Remove the ailerons from the wing and set them aside until time for covering.

Completing The Wing

36.

Use a sanding block with 80 grit sandpaper to give the entire wing a final sanding. Sand just enough to take off any prominent high spots and to smooth out any mismatched joints between parts. Sand all wing sheeting down flush with the spars, leading edges, and trailing edges. Avoid sanding into the spars, leading edges, and trailing edges themselves as much as possible, just sand the wing sheeting pieces down to them! if youíve got sheet that is lower than the spars, etc. then fill in the low spot with light-weight wood filler and sand smooth. You shouldnít have to sand the edges of the wing ribs at all - they should already be level with the surface of the spars, etc. However, you may need to use a small sanding block to touch up any excess glue on the rib to spar joints. Excessive sanding of the ribs themselves will distort the airfoil shape.

37.

On the bottom of the wing, draw a short line parallel to and 1/2" aft of the main spar. Draw a second line, 2-1/8" aft of the main spar. Cut a opening 1" wide x 1-5/8" long in the bottom of the wing sheeting for the aileron servo.

38.

Remove the aileron servo mount from the Laser-Cut sheet #19. Use Slow CA to glue it in place on the bottom of the wing. Make sure the plywood mount is centered over the cutout that in the wing sheeting. Use enough glue to fill in the gap under each side of the aileron servo mount, caused by the dihedral angle.




Reinforce Wing Center Joint

39.

A 1" wide x 24" long piece of fiberglass cloth tape is supplied to reinforce the joint between the Right & Left Wing Panels. Cut the 24" long tape into one 18" long piece and one 6" long piece. Lay the 18" long piece of fiberglass tape over the center joint on top of the wing. Using a small amount of Thin CA, tack glue the end of the tape to the Trailing Edge. Make sure the width of the tape is overlapping 1/2" onto the Right Wing Panel and 1/2" onto the Left Wing Panel.

After the Thin CA dries, pull the other end of the tape completely around the Leading Edge and down onto the bottom surface of the wing. The tape should lay nice and flat, tight against the top surface of the wing. Again make sure the tape is centered over the joint - half on the Right Wing Panel and half on the Left Wing Panel. Then tack glue the tape to the Leading Edge.

Now carefully flow Thin CA glue into the tape on top of the wing. Use just enough glue to saturate the tape - too much glue will run outside the tape and get all over the place. If you do get too much glue on the tape, take a clean rag and quickly wipe off the excess before it dries (donít rub too hard and disturb the tape position). By working slowly and gluing small (3" long) sections of tape at a time, you should be able to glue the entire length of tape in place without wrinkles or bumps.
CAUTION: Do the gluing in a well ventilated area to avoid breathing the fumes from the Thin CA glue!

After youíve finished gluing the fiberglass tape on the top of the wing, turn the wing over and glue the remainder of the original 18" long piece to the bottom front of the wing. Cut it off right in front of the plywood ASM part.

Using the same techniques, glue the 6" long piece of fiberglass tape to the bottom of the wing. It goes from the back of plywood part ASM, all the way off the end of the wing. When dry, cut it off flush with the end of the wing. NOTE: Be very careful when gluing the tape in the area of the Torque Rods! If you get too much Thin CA in that area, the excess could seep into the Torque Rods, binding them up permanently.

After all the glue is dry, lightly sand the fiberglass cloth with a piece of 220 grit sandpaper to remove any lumps or high spots. Be careful not to sand through the fiberglass cloth.

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FUSELAGE CONSTRUCTION

NOTE: You will need to have the engine that you will be using before starting on the fuselage construction.

40.

Mark the vertical center line and thrust line on the front of firewall F-1. Notice that there are small "tic marks" (cuts) burned iinto the front of F-1 which indicate the proper locations of these lines.

41.

Set your engine on the front of F-1 as shown in the photo, with the crankshaft of the engine directly in line with the vertical center line. Make two pencil marks on the Firewall, one on each side of the engineís crankcase, to indicate where the inside of the of the two Engine Mounts should be.

42.

Draw a vertical line through both of the pencil marks you made in the previous step. Make sure that both lines are exactly parallel to the vertical center line.




43.

Line up the inside edges of the Engine Mounts with the vertical lines you made in the previous step. Also make sure that the top suface of the beams of the Mounts (where the engine will sit) are lined up with the thrust line. When you are sure that you have the Mounts positioned properly, mark the four mounting holes on the Firewall, and then drill the holes with a 11/64" drill bit.




44.

Bolt the Engine Mounts loosely to the Firewall with four 6-32 x3/4" Mounting Bolts and 6-32 Blind Nuts. Double check the position of the Mounts one more time, and then tighten the Bolts until the prongs of the Blind Nuts are just started into the wood and holding firmly.

Now loosen the Bolts and remove the Engine Mounts from the firewall. Seat the Blind Nuts completely into the wood with a hammer.

Apply a little Medium CA glue around the flanges of the Blind Nuts to keep them from coming loose. Be careful not to get any glue in the threads of the Blind Nuts.
When the glue has cured, bolt the Engine Mounts back onto the Firewall.

45.

Position your engine on the Engine Mounts, with the back of the Spinner back plate approximately 3-5/16" away from the front of the Firewall. This is done so the back of the spinner will clear the fuselage "cheeks".

View down on the engine from above to make sure that the engine is pointing straight ahead, without any left or right side thrust.

NOTE: 0į side thrust is the ideal! However a slight amount of RIGHT thrust would also be OK, but under no circumstances should you have left thrust!




Hold the engine in correct position on the Mounts while you use a pencil to mark the locations of the engineís mounting holes onto the Mounts.

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Remove the Engine Mounts from the firewall and drill down vertically thru the beams of the Mounts, on the pencil marks, with a 1/8" drill bit (use a drill press if available).

46.

Bolt the Engine Mounts back onto the Firewall. Then bolt the engine to the Engine Mounts using the 4-40 x3/4" Mounting Bolts and 4-40 Aircraft Lock Nuts provided.

Next we need to mark and drill the location for the Throttle Pushrod to pass through the firewall. Note: In most 2-cycle engine installations, this will be approximately as shown in the photo. However be sure to determine whether this will work OK for your particular engine. Then drill a 9/64" hole at this mark for the outer housing of the flexible cable.

When done, unbolt the Engine Mounts from the firewall, leaving the engine bolted to the Mounts. Set the engine/engine mount combination aside until needed later.




47.

Bolt the Aluminum Landing Gear onto the 3/16" laser-cut plywood Landing Gear Mount using 4-40 x1/2" Mounting Bolts and 4-40 Blind Nuts provided. Tighten the Bolts until the prongs of the Blind Nuts are just started into the wood and holding firmly. Then remove the Aluminum Landing Gear and seat the Blind Nuts completely into the wood with a hammer. Apply a little Medium CA glue around the flanges of the Blind Nuts to keep them from coming loose. Be careful not to get any glue in the threads of the Blind Nuts.

48.

Glue laser-cut lite-ply former F-2D in place at the top of lasercut balsa former F-2. Be careful to get the top and side edges of the formers flush with each other.

49.

Glue the laser-cut lite-ply Tailwheel Mount onto the aft end of the balsa wood Fuselage Bottom Rear. Make sure the small hole in both parts line up with each other.

50.

Glue a laser-cut balsa Fuselage Doubler in place on each laser-cut balsa Fuselage Side. NOTE: Study the full-size plan to make sure you know exactly where the Fuselage Doubler should go before you apply the glue. There are some places where the edges of the Fuselage Doubler should be flush with the edges of the Fuselage Side, and that there are other places where the Fuselage Doubler is inset 1/8" away from the edge of the Fuselage Side. Use a slow drying glue to allow you plenty of time to accurately position the Doubler before the glue dries. Pin flat to the building board until dry.

CAUTION: Be sure to make one RIGHT and one LEFT fuselage side assembly!




51.

With the right Fuselage Side pinned flat to the building board, glue the Firewall in place in the first notch in the Fuselage Doubler. Use a 90į triangle to keep Firewall perpendicular to the Fuselage Side. Let the glue dry before proceeding.

Next glue the F-2 former assembly in place on the right Fuselage side in the same manner you just did the Firewall. Be sure to glue it in with the F-2D part of F-2 facing forward (towards the nose - see side view of Fuselage plan.) When dry, unpin the right Fuselage Side from the building board.

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52. Pin the left Fuselage Side down to the building board. Join the right and left Fuselage Sides together by gluing formers F-1 and F-2 into the notches in the left Fuselage Side.
Again use a small 90į triangle to keep the formers perpendicular to the fuselage side.

Let dry.

53.

Fit the laser-cut balsa Fuselage Bottom Rear between the two Fuselage Sides, using masking tape to hold it in place. DO NOT GLUE AT THIS TIME!


54.

Identify the laser-cut balsa formers F-3, F-4, F-5, and F-6, and carefully match them up with their respective cross-section drawings on the full-size fuselage plan (Plate 1). Make sure that you have all the pre-cut holes in the formers properly oriented. Then mark each former as to its correct top and front side with a pencil.
NOTE: IF THIS STEP IS NOT DONE CORRECTLY, THE ELEVATOR AND RUDDER PUSHRODS WILL NOT INSTALL PROPERLY LATER.

55.

Carefully install formers F-3, F-4, F-5, and F-6 in the fuselage, making sure that you have the front of the formers facing the front of the fuselage (towards the nose). Do not glue in at this time!


56.

Fit the laser-cut balsa Fuselage Top Rear and the laser-cut balsa Stab Mount between the two Fuselage Sides, using masking tape to hold them in place. DO NOT GLUE AT THIS TIME! Make sure the rudder exit slot in the Fuselage Top Rear is on the right side of the fuselage.

Double check to see that the entire fuselage structure is in correct alignment. Make sure that the entire structure is straight and square and that all the parts are taped tightly together before proceeding.

57.

Now you can start gluing the fuselage parts together! Use MEDIUM CA glue, and start with small patches of glue in the corners, checking the fuselage alignment as you go. Keep applying glue until the complete inside of the fuselage has been gone over once. Now go back and glue all of the joints on both sides. Leave the tape in place until all the glue has cured completely.

58.

Turn the fuselage assembly upside down on the workbench and glue the laser-cut plywood Landing Gear Mount inplace. Glue it to all the surrounding parts, the doublers and the bottom of former F-2. Donít be stingy with the glue or you may find yourself picking up the landing gear as a separate piece after a hard landing.

59.

Cut four 7/8" long pieces of 1/2" balsa triangular stock from the 12" long piece provided. Glue these four pieces inside the fuselage to reinforce the Landing Gear Mount installation (see full-size plan). Note: You will need to cut notches in the triangle stock that goes behind former F-2 to clear the blind nuts in the Landing Gear Mount.



60.

Glue the laser-cut balsa Fuselage Bottom Front in place with MEDIUM CA. Be sure to glue the joint between Fuselage Bottom Front and the Landing Gear Mount. Glue in the laser-cut balsa Nose Bottom.

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61. Cut two pieces of 1/2" balsa triangle to glue onto the back of the firewall to reinforce the firewall-to-fuselage joint (see full-size plan). Cut notches in the triangle where necessary to clear the blind nuts and pushrod hole. Glue the triangles firmly in place.

62.

Glue the laser-cut balsa Tank Floor into the nose. The Tank Floor should sit flat on the ledges created by the Fuselage Doublers, with the front of the Tank Floor up against the back of Firewall.

63.

Glue in the laser-cut balsa Windshield in place.




64.

Lightly block sand the Hatch area to remove any bumps, glue spots, or mismatch between the fuselage sides, the doublers and the top of the firewall. Be careful not to sand a curve in the fuselage sides which would cause an unsightly gap when the Hatch is installed.

65.

Locate the laser-cut plywood Hatch. Inspect both sides and choose the best looking side for the top. Draw guidelines on the bottom of the Hatch for the location of the Hatch Tongue. The guidelines should be 1/4" in from each side, and 3/8" down from the back end of the Hatch (see full-size Plan Sheet 1). Glue the laser-cut plywood Hatch Tongue in place on the bottom of the Hatch.

66.

Tape the Hatch in place on the fuselage. Using the hole in the Hatch as a guide, drill a 1/16" dia. pilot hole in the top edge of the firewall. Screw the Hatch down with a #2 x 3/8" Sheet Metal Screw and #2 Flat Washer.




67.

Two pieces of 3/16" o.d. x36" Large Nylon Pushrod Tubing are provided for making the outer casing of the Elevator and Rudder Pushrods. Cut one piece for the elevator pushrod to an overall length of 26-1/2". The piece for the rudder pushrod will be cut off later in Step 69, so leave it full length for now.
Study the fuselage top and side views on full-size Plan Sheet 1 to familiarize yourself with the proper location for each pushrod. Make a mark at 4-3/4" from one end of each outer casing - this will be the servo end of the tube that sticks out in front of former F-3. Feed each tube into place in the fuselage, starting from the front and sliding them into the proper holes in the formers.
When you've got both tubes properly positioned, glue them permanently to all the formers with Thick CA.


68.

Cut two 5" long pieces of the 1/8" o.d. Small Nylon Pushrod Tubing from the 20" long piece provided (save the remainder for the throttle pushrod - see Step 70). These will be the Pull-Pull Cable Guides. Glue them in place in the slots in the aft end of the Fuselage Bottom Rear. Note that the rear ends of the tubes should be outside the fuselage, while the front ends of the tubes should be on the inside.

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69. Use a long blade on a modeling knife to cut off the excess rudder pushrod tube (from Step 67) and the pull-pull exit tubes (from Step 68). Cut the tubes as close as you can to the fuselage. Then block sand the tubes, and any excess glue, flush with the fuselage.

70.

Glue the 10" long piece of 1/8" o.d. Small Nylon Pushrod Tubing (left over from Step 68) into the hole in the Firewall for the Throttle Pushrod. Leave about 2 inches of the tubing extending in front of the firewall.







71.

The fuselage is now ready for final sanding. Use a sanding block with 80 grit paper to sand smooth all the exterior glue joints on the sides, top and bottom of the fuselage. Sand all protrusions until they are level with the surface. Block sand the exterior corners of the fuselage slightly round for a more pleasing shape. The cross sections on Plan Sheet 1 can be used as reference for shape. Do not round the corners in the areas where the wing and stabilizer will be mounted or in the Hatch area. After leveling everything with the 80 grit sanding block, go over the entire fuselage with hand held 220 grit sandpaper.
The basic fuselage construction is now complete! Set the fuselage aside until covering.

Stabilizer And Elevator

72.

Tape the Stabilizer Plan to the building board, and cover with wax paper. Pin down over the plan and glue in place all of the 5/16" laser-cut balsa stabilizer parts S-1, S-2, S-3, S-4, S-5, and S-6. Cut four 5/16" sq. balsa ribs from the 30" long piece provided, and glue them in place with THIN CA.


73.

Once the glue is dry, remove the Stabilizer frame from the plan and re-glue all the joints with Medium CA. Use just enough glue to completely fill the joint, plus leave small fillet of glue between the parts. Take your time and donít miss any joints! Each and every one of them contributes to the finished strength of the Stabilizer.

74.

Lay the Stabilizer flat on the building board and lightly block sand both sides to smooth out all the glue joints.
CAUTION: Do not sand so much that you thin down the Stabilizer more than 1/32" under its original 5/16" thickness.

75.

Mark a center-line on the front of the Stabilizer Leading Edge. Using the center-line as a guide, carve and sand the Leading Edge round. NOTE: Leave the trailing edge and ends of the Stabilizer flat and square.

76.

Temporarily tape the pre-shaped Elevator to the back of the Stabilizer. Use a sanding block to even up the tips of the Elevator and Stabilizer. Set the Stabilizer and Elevator aside until time to cover.



.

Fin And Rudder

77.

Tape the Fin plan to the building board, and cover with wax paper. Pin down over the plan and glue in place all of the 5/16" balsa laser-cut fin parts. Cut two 5/16" sq. balsa ribs and glue them in place with THIN CA.




78.

Once the glue is cured, remove the Fin Frame from the plan and re-glue all the joints with Medium CA. Use just enough glue to completely fill the joint, plus leave small fillet of glue between the parts. Take your time and donít miss any joints! Each and every one of them contributes to the finished strength of the Fin.

79.

Lay the Fin flat on the building board and lightly block sand both sides to smooth out all the glue joints.
CAUTION: Do not sand so much that you thin down the Fin more than 1/32" under its original 5/16" thickness.

80.

Mark a center-line on the front of the Fin Leading Edge. Using the center-line as a guide, carve and sand the Leading Edge round.
NOTE: Leave the trailing edge, top end, and bottom of the Fin flat and square.

81.

Locate the pre-shaped balsa Rudder. Compare the overall height of the Rudder to the overall length of the Finís trailing edge. Notice on the plan that the Rudder should be 3/8" shorter in height than the Finís trailing edge. This is to provide a gap between the bottom of the Rudder and the top of the Stabilizer after the model is assembled. Sand the end of the Rudder slightly if necessary to achieve an adequate gap. Sand the sides of the Rudder smooth with 220 grit sandpaper. Set aside until ready for covering.