KADET LT-40 RC67 WING PANEL CONSTRUCTION

The KADET LT-40ís wing is designed to be built in two halves - called the LEFT WING PANEL and the RIGHT WING PANEL (see full-size Plan Sheet 2). Each wing panel should 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 (the one you are not using) to see what is covered up.

Letís get started by building the LEFT WING PANEL first!

REMEMBER:
These instructions are written assuming the use of MEDIUM CA glue for all steps, unless otherwise noted. In other words, if an instruction simply says "glue" part A to part B - use MEDIUM CA!

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. Then cover the plan with a sheet of wax paper, also taped down. This will keep excess glue from sticking to the plan when you are gluing the parts in place.




2.

Locate two 1/4"x1/2"x36" hardwood pieces for the Main Wing Spars and two 1/4"x1/2"x10-1/8" balsa pieces for the Spar Doublers (see the wing cross-section drawings on Plan Sheet 2 to understand the location of the Spar Doublers). Use Slow CA to glue a Spar Doubler onto one end of each Main Wing Spar, making sure that the sides of the pieces are flush with each other before the glue dries.

3.

Pin one of the Main Wing Spar assemblies from the previous step in position on the plan. This assembly will now be referred to as the Bottom Main Spar.
IMPORTANT: Position the Bottom Main Spar on the plan precisely by lining up the inboard end of the Spar Doubler flush with the location of the first W5 wing rib (look for note on plan that says "1/4"x1/2" BALSA SPAR DOUBLERS END HERE).

4.

Use a razor saw to cut off the excess tip end of the Bottom Main Spar flush with the outside edge of the last W5 wing rib (see note on plan, "BOTTOM SPAR ENDS HERE").

5.

Pin die-cut balsa wing sheeting piece WS-B2 in place on the plan, gluing its front edge to the back of the Bottom Main Spar at the same time.

6.

Locate one 1/4"x3/8"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 WS-B2 at the same time. Cut off the tip end of the Bottom Rear Spar flush with the outside edge of the last W5 wing rib (see note on plan, "BOTTOM SPAR ENDS HERE").




7.

Pin die-cut balsa wing sheeting piece WS-B3 in place on the plan, gluing its front edge to the back of the Bottom Rear Spar at the same time.

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8. Pin the pre-shaped balsa Trailing Edge in place on the plan, gluing it to the back edge of WS-B3 at the same time. Be sure to align all of the notches in the Trailing Edge with the wing 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 Edge!


9.

Carefully remove all the wing ribs (W1 through W5) from die-cut sheets #1, #2, and #3. Take time to familiarize yourself with the ribs and how they differ. You will notice that ribs W1, W2, W3, and the front of rib W4 are smaller than the W5 ribs to all allow for the 3/32" thick balsa wing sheeting pieces. There are also some differences between the size of the spar cutouts in each rib.


10.

Glue wing ribs W2 and W3 in place. They should be glued to the Bottom Main Spar, the Bottom Rear Spar, the WS-B2 and WS-B3 wing sheeting, and the Trailing Edge. Make sure the ribs are sitting up straight, perpendicular to the building board before the glue dries.

11.

Glue one SW-2 Shear Web in place on top of the Bottom Main Spar, and up tight against rib W3.

12.

Glue one SW-3 Shear Web in place on top of the Bottom Rear Spar, and up tight against rib W3.

13.

Glue rib W4 in place, gluing it to the Bottom Main Spar, the Bottom Rear Spar, the Trailing Edge, and to the ends of Shear Webs SW-2 and SW-3.

14.

Glue another SW-2 Shear Web to the Bottom Main Spar and another SW-3 Shear Web to the Bottom Rear Spar, also gluing them against rib W4.




15.

Next glue the first W5 rib in place, followed by a SW-1 Shear Web on the Bottom Main Spar and a SW-3 Shear Web on the Bottom Rear Spar. Continue this procedure of gluing in a rib, followed by the adjoining Shear Webs, until all the remaining W5 ribs and Shear Webs are glued in place.

NOTE: There are no SW-1 Shear Webs called for in the last two rib bays nearest the wing tip, nor any SW-3 Shear Webs in the last three rib bays nearest the wing tip.

16.

Now trial fit the other Main Wing Spar assembly (that you made back in step 2) in place in the top front notches in the wing ribs. This is now referred to as the Top Main Spar. Make sure that the end of the balsa Spar Doubler lines up flush with the side of the first W5 wing rib. When satisfied with the fit, glue the Top Main Spar assembly permanently to all the wing ribs.

17.

Locate a 1/4"x3/8"x36" balsa stick for the Top Rear Spar and glue it in place in the top rear notches in the wing ribs.
NOTE: The tip end of the Top Rear Spar is also extra long. Do not cut it off at this time - we will do that later, after the wing tip is installed.

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18. Glue the pre-shaped balsa Leading Edge in place in the notches in the front of the wing ribs.

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 drawings on Plan Sheet 2, and after you are sure that you have it matched up correctly, mark an "up" arrow on one end. Then make sure you glue it into the wing right side up!

NOTE:
By the way, youíve probably already noticed that the tip end of the Leading Edge is also too long, just like the Top Main Spar & Rear Spar! Guess what? Do not cut the Leading Edge off at this time - we will do that later, after the wing tip is installed.

19.

Remove part DRG (dihedral root gauge) from die-cut lite-ply sheet #11. Match it up to the full-size pattern (left) and mark the correct edges as indicated - TOP, BOTTOM, DIHEDRAL ANGLE, and RIB W2.




20.

Hold DRG up against the Top & Bottom Main Spars, with the bottom edge of the gauge down tight against the wing sheeting and the "RIB W2" edge up tight against rib W2. Use a pencil to draw along the "DIHEDRAL ANGLE" edge onto the Top & Bottom Main Spars. Next mark the Top & Bottom Rear Spars in the same manner. These lines represent where the outside face of rib W1 will be installed.




21.

Carefully slide wing rib W1 into position in the root end of the wing panel. Notice that W1 should not be installed straight up and down like all the rest of the wing ribs, but rather it must have its top tilted slightly towards the wing tip to provide the finished wing with the proper amount of dihedral angle (see Wing Front View on Plan Sheet 2). Before you glue W1 to any of the wing structure, eyeball it from several different angles to verify that it is in the correct position. Use DRG and the line up marks you put on the spars in the last step, as guides for getting the tilt of W1 exactly right. To double check the alignment, look straight down on the W1 rib from directly above to make sure its bottom edge is properly aligned with the edge of the wing sheeting. If it is, go ahead and tack glue the bottom of W1 to the wing sheeting with a couple small drops of Thin CA glue. Next, use DRG in the manner shown here (notice itís upside down compared to step 20) to keep W1 tilted at the proper angle while you glue it to the Top Spars, the Leading Edge, and the Trailing Edge with Thin CA. After W1 is secured into correct position, go back and re-glue the entire bottom of the rib to the wing sheeting.

22.

Once all the glue joints are dry, you can unpin the Left Wing Panel from the building board!


23.

Now we can add the wing tip! The only way to get the die-cut lite-ply WTP (wing tip plate) 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.

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24. Once in position, securely glue WTP to all the other parts it comes in contact with.

NOTE: Practically everywhere that WTP comes in contact with another part there are angles involved. This means there will naturally 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 light-weight wood filler later on during preparation for covering.



25.

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

26.

Glue die-cut balsa wing sheeting piece WS-T3 in place on the top of the wing, between the Top Rear Spar and the Trailing Edge.




27.

Glue die-cut balsa wing sheeting piece WS-B1 in place on the bottom of the wing, between the Bottom Main Spar and the Leading Edge.
NOTE: There will be a wedge-shaped gap where WS-B1meets the Leading Edge. This is normal! Simply run a bead of Slow CA in the gap and let it dry - this will secure WS-B1 to the Leading Edge. Fill the rest of the gap with light-weight wood filler before covering.

28.

Carefully saw off, and then block sand, the root ends of the Spars, Leading Edge, and Trailing Edge flush with the pre-angled W1 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 W1.

29.

Look closely at rib W1 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 1/4" from the bottom of the rib. In this step, you will complete the aileron servo cutout in rib W1! First lay the wing panel flat on the workbench and use a modeling knife to cut straight down through the last 1/4" of rib on both vertical legs. Stop cutting when you get to the bottom wing sheeting. Then carefully break out the portion of the rib inside the cutout area.






The LEFT WING PANEL is now complete!
Repeat Steps 1 through 29 to build the RIGHT WING PANEL!

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JOINING THE WING PANELS

30.

The first thing you need to do is check the fit of the two wing panels to each other - WITHOUT GLUE! Start by locating die-cut lite-ply part DTG (dihedral tip gauge) and pinning it to the underside of the last W5 rib (nearest the wing tip) in the Left Wing Panel. The notches in the DTG should straddle both bottom wing spars.



31.

Lay the Right Wing Panel on a large flat surface, such as a big table or on the floor. Mate the root end of the Left Wing Panel up against the root end of the Right Wing Panel. The DTG (pinned to the wing tip of the Left Wing Panel) will set the proper dihedral angle by holding the left wing tip up 3-3/4" off the table (see halfsize Wing Front View on Plan Sheet 2). Make sure the leading and trailing edges of both wing panels are perfectly aligned with each other so that there is no twist between the panels. Look for gaps between the W1 root ribs. If you installed both W1 ribs at the correct angle, and you sanded all the spars, etc. perfectly flush with the W1 ribs, then you should not have any significant gaps. A small gap of 1/16" or less is insignificant and will be OK. If you have a larger gap, you will have to figure out how it happened and correct it before going on to the next step.

32.

Locate the two laser-cut plywood MADB (main dihedral braces). Using the full-size pattern of MADB as a guide, mark a center-line on the front and back of both braces.

33.

Use a modeling knife or razor saw to cut out the portions of the W1 root rib where the MADBs will go. Do this to the W1 rib in both wing panels. TIP: Use a pencil and straight edge to mark guidelines on the rib before cutting. Make repeated short shallow cuts until you get all the way through the wood, whether you are using a knife or saw. This will help avoid splintering the rib!


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34. Carefully slide both MADBs into position in the Right Wing Panel. Push them in slowly, being careful not to snag and break the W1 or W2 ribs. Position both MADBs carefully before gluing them to the spars.
Check:
  1. that the MADBs are tight against the front and back of the Top & Bottom Main Spars;
  2. that the MADBs are exactly halfway in the Left Wing Panel - the center lines you drew on the MADBs should line up with the outside face of W1;
  3. that the bottom edges of the MADBs are down tight against the bottom wing sheeting;
  4. that the exposed ends of the MADBs line up with each other from the front view. When all of these checks are OK, glue the MADBs to the main spars with Thin CA glue. Mop up any excess Thin CA with a rag. Let dry.

35.

WITHOUT GLUE, slide the Left Wing Panel onto the exposed ends of the MADBs, again being careful not to break the W1 or W2 ribs. Once again set-up the entire wing assembly on a large flat surface with the Right Wing Panel flat on the table and the Left Wing Panel propped up by the gauge DTG - just as you did in step 31.



(If the MADBs are preventing the wing panels from fitting like they did before, trim or sand the MADBs where necessary to eliminate the problem.)

Make sure the opposing Leading and Trailing Edges are lined up with each other so there is no twist between the wing panels. Use plenty of pins to hold the wing panels tightly together in correct alignment. Once everything looks good, use Thin CA to glue the MADBs to the main spars in the Left Wing Panel. Do not apply glue anywhere else yet! When dry, you should be able to pick up the entire wing assembly without fear of the wing panels shifting. The glued MADBs and the pins should hold everything together adequately for the next step.

36.

Pick up the wing assembly, turn it over, and put a strip of masking tape along the entire center joint on the bottom of the wing. Now turn it back over and flow Thin CA glue into the center joint from the top. Run the glue in along the entire length of the W1 ribs. Use just enough glue to flood the entire joint, but not so much that it runs all over the place. The masking tape should keep the glue from running out the bottom. Have a rag handy to mop up any excess glue. If you have some gaps that the Thin CA wonít fill in, switch to Medium CA or Slow CA to fill them. Let dry! Then remove the masking tape and all the pins.

37.

Before you can put on the rest of the top wing sheeting, you must go back and re-glue ALL the joints that will be inside the sheeted area. Make sure there is a visible, but small, fillet of glue in every joint. Donít let any excess glue get on top of the ribs, or along the spars, where the WS-T1 and WS-T2 wing sheeting pieces will go.

38.

Glue the two WS-T2 die-cut balsa wing sheeting pieces in place between the top rear spars and the top main spars.

39.

Glue the two WS-T1 die-cut balsa wing sheeting pieces in place between the top main spars and the leading edges.

40.

Now go back and re-glue every joint in the wing with Medium CA or Slow CA glue! Make sure there is a visible, but small, fillet of glue in every joint. Take your time and donít miss any joints! Each and every one of them contributes to the finished strength of the wing.

AILERON INSTALLATION

41.

Locate the two pre-shaped balsa Center Section Trailing Edge pieces. They are identical to each other at this point, but by the time you finish the next step they wonít be - so mark LEFT (BOTTOM) on one piece and RIGHT (BOTTOM) on the other.

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42. On the LEFT (BOTTOM) Center Section Trailing Edge piece, draw a box 1/4" wide x1/2" deep, exactly 7/16" from the end.

43.

Continue the lines down the front of the piece, until you reach the bottom of the pre-cut groove in the front.




44.

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.

45.

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

46.

Repeat steps 42 through 45 to make the RIGHT (BOTTOM) Center Section Trailing Edge a mirror image of the Left one.

47.

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.




NOTE: The threaded portion 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-40 with a small amount of "differential" movement in the ailerons (more up than down), which makes for smoother turning.

48.

Use a small amount of Slow 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.


TIP: Itís not necessary to apply glue along the full length of the Brass Bearing. Keep all glue 1/8" away from the ends of the Brass Bearing to minimize any chance of glue seeping inside the bearing and causing a bind in the movement of the Torque Rod.

49.

Repeat step 48 to glue the Right Aileron Torque Rod into the groove in the front of the Right Center Section Trailing Edge.

50.

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 until the glue dries. Use a straight edge to confirm that the bottom surface of the part is flush with the bottom surface of the wing. Let dry.

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51.

Repeat step 50 to glue the Right Center Section Trailing Edge in place on the back of the wing, also gluing it to the Left Center Section Trailing Edge at the same time.



52.

Double check to verify that both Aileron Torque Rods will pivot freely. If they donít, you must find the problem and correct it now, before going on to the next step.

53.

Locate the two pre-shaped balsa wood Ailerons. Using a 3/32" dia. drill bit, drill a hole 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. The hole should be 5/8" deep.

54.

Use a modeling knife to cut a (3/32" wide x3/32" deep) groove in the leading edge of each aileron to accept the Aileron Torque Rod wire. The groove should go from the 3/32" hole you drilled in the last step to the root end of the aileron. Trial fit (without glue) the aileron over the end of the Torque Rod wire to check the fit.

55.

Mark the locations for the Sig Easy Hinges (4 per aileron) on the leading edge of the ailerons and on the trailing edge of the wing.



56.

Cut slots for the hinges in the Ailerons and Wing following the instructions "INSTALLING SIG EASY HINGES" at the end of this wing construction section (perform steps 1 and 2).

57.

Once all the slots have been cut, insert a single Easy Hinge halfway into each slot in the trailing edge of the wing. DO NOT GLUE THE HINGES IN AT THIS TIME!

58.

Now carefully slide the ailerons onto the exposed half of the Easy Hinges, and onto the exposed arm of the Torque Rod, all at the same time. You will find it easiest to slide the ailerons onto the hinges at angle, one hinge at a time, starting from the tip end, instead of trying to push it straight onto all the hinges at once. ONCE AGAIN, DO NOT GLUE THE HINGES IN AT THIS TIME!

59.

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




60.

Pin a piece of scrap balsa or plywood 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.

61.

Razor saw and block sand the end of the aileron to match the shape of the wing tip. Here are a couple different views showing the proper final shape of the wing tip/aileron tip area.

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62. Remove the ailerons and hinges from the wing and set them aside until "COVERING THE KADET LT-40" .





COMPLETING THE WING


63.


Use a sanding block with fresh 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.



Be sure to block sand all the WS-* wing sheeting pieces 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 sheeting that is lower than the spars, etc., then fill in the low spot with light-weight wood filler and sand that 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, the rib-to-leading edge joints, and the rib-to-trailing edge joints. Excessive sanding of the ribs themselves may distort the airfoil shape.

64.

Make an opening (1" wide x2" long) in the bottom wing sheeting for the aileron servo. Mark and cut out the opening according to the dimensions shown here:
  • Front edge of the cutout = 1/2" aft of the main spar.
  • Rear edge of the cutout = 2-1/2" aft of the main spar.

65.

Remove part ASM aileron servo mount from die-cut plywood sheet #14. Use Slow CA to glue ASM in place on the bottom of the wing. Make sure the cutout in the middle of ASM is centered over the opening in the bottom wing sheeting. Use enough glue to fill in the gap under each side of ASM, caused by the dihedral angle.

66.

Glue both 1/16"x1"x3-5/16" plywood Trailing Edge Stiffeners in position along the top trailing edge of the wing.



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REINFORCE WING CENTER JOINT

67.

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.

68.

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 balsa Center Section Trailing Edge, right in front of the 1/16" plywood Trailing Edge Stiffeners. Make sure the width of the tape is overlapping 1/2" onto the Right Wing Panel and 1/2" onto the Left Wing Panel.

69.

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.

70.

Now carefully flow Thin CA glue onto 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 positioning of the tape). 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 any major wrinkles or bumps.

CAUTION: Do the gluing in a well ventilated area to avoid breathing the fumes from the Thin CA glue!

71.

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.

72.

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.


73.

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.


The basic wing construction is now complete! Set the wing aside until "COVERING THE KADET LT-40"


INSTALLING SIG EASY HINGES

WARNING:
SIG EASY HINGES are designed to be used in conjunction with Thin CA glue. Thin CA (any brand) is the ONLY type of glue that can be used on EASY HINGES - do not use epoxy or any other type of glue on EASY HINGES!

Each ultra-thin EASY HINGE is actually a 3-part laminate - a tough plastic inner core sandwiched between 2 layers of absorbent wicking material. They have been chemically treated to slow down the drying time of Thin CA (which is normally instant), to allow the glue time to soak all the way to the ends of the hinge and into the wood surrounding it. Once the glue has dried, the hinge cannot be pulled from the structure without tearing wood out with it.

1.

Begin by carefully cutting a very shallow slit at the hinge location using a fresh, sharp #11 blade in your modeling knife. This first slit should be very shallow so you can better control the direction of the knife. It's main purpose is to establish your hinge slot in the right place, so concentrate on staying on the hinge line and don't try to cut too deep.
NOTE: Make the slit slightly wider than the actual hinge.

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2.

Now make 3 or 4 more cuts in the exact same line, going slightly deeper each time. As you make these additional cuts, concentrate on staying in the slit and keeping the blade headed straight into the center of the wood so that it wonít come out the side of the part. You will find that as the blade gets deeper into the wood, it will become harder to move it along the slot. Try "wiggling" the knife handle in the slot to make it cut, instead of trying to "slice" the blade along in one continuous motion. Continue making additional cuts until the slot is approximately 1/2" deep.


CAUTION: You must use extreme care to avoid cutting yourself while cutting the hinge slots. If the balsa wood breaks while you are pushing on the knife, the blade could go into your hand before you can stop it. A good precaution is to wear a leather glove on the hand that is holding the model part while you are cutting the slots.

3.

After all the slots have been cut, insert a single Easy Hinge halfway into each hinge slot in the stabilizer (or fin, or wing, as the case may be). If the hinge is difficult to push in, re-insert the knife and move it back and forth in the slot a few more times and then try again. DO NOT GLUE THE HINGES IN AT THIS TIME!


4.


Now carefully slide the elevator (or rudder, or aileron) onto the exposed half of the Easy Hinges. You will find it easiest to slide the part onto the hinges at angle, one hinge at a time, instead of trying to push it straight onto all the hinges at once. Donít be overly concerned if the hinges donít end up perfectly straight or centered in the slots - they do not have a center line.
ONCE AGAIN, DO NOT GLUE THE HINGES IN AT THIS TIME!


5.

To set the proper amount of gap between the model parts, simply deflect the control surface to the maximum amount of travel needed. This will automatically set the proper hinge gap! Keep in mind that for best control response the gap should be kept as small as possible, but big enough to allow full movement of the control surface. If everything appears to function properly, remove the parts and take the hinges out of the slots. Set everything aside until after the model has been covered.

THE MODEL PARTS SHOULD BE COMPLETELY COVERED BEFORE PROCEEDING TO THE NEXT STEP!

6.

After the model parts have been covered, use the X-Acto knife to re-open the hinge slots by cutting through the covering that went over them. Re-install the hinges and re-adjust the hinge gap.


7.

Place three or four drops of Thin CA glue directly onto the Easy Hinge in the gap. You will notice that the glue is quickly wicked into the slot as it penetrates both the wood and the hinge. Turn the part over and glue the other side of the Easy Hinge. Continue this process until you have glued both sides of all the Easy Hinges! Keep a rag handy to wipe off any excess Thin CA. (CA glue residue can be cleaned from most iron-on plastic covering materials with CA Debonder).

VERY IMPORTANT: Make only one application of glue to each side of an Easy Hinge! If you apply additional glue to the hinge after the first application of glue is already dry, the second application of glue will merely puddle in the hinge gap and make the hinge too stiff to operate properly. The excess glue could also weaken the hinge! When properly glued, the portion of the Easy Hinge that you can see in the hinge gap should have a dry appearance, not wet. A dry appearance indicates that almost all of the glue has properly soaked into the hinge slot. A wet appearance indicates that excess glue is puddled in the hinge gap. Three to four good size drops of Thin CA should be about the right amount.

NEVER USE CA ACCELERATOR ON EASY HINGES!

8.

Let the glue dry a minimum of 3-5 minutes before flexing the hinges. At first you might notice a little stiffness in the joint. This will go away after the hinges have been flexed back and forth a couple dozen times.