Building an aileron Taboo XL wing


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IHLGF 2002
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This page describes the process of building an aileron wing for a Taboo XL. The techniques shown here are not specific to Taboo XL and in large part can be applied to any other HLG kit, except in places where the supplied hardware dictates one or the other way of construction (e.g., your control horns are likely to be different unless you purchase the same ones that I supply with the kit). For the polyhedral wing, you can either use the applicable steps in these instructions, or visit the web-page for the old Taboo kit and check out the on-line instructions for the polyhedral wing there. You can also use that page for photos of the fuselage and tail assembly.
The wing assembly process starts with cutting the servo wells. The easiest way of cutting nice tight servo wells is to first cover a small area of the wing skin with masking tape, then trace the servo outline with a pencil, and cut along the lines with X-acto knife. Be careful not to damage the top skin.
After you have cut the servo wells, prepare the wing root for joining the panels. Clear and enlarge the wire channels at the joint. Carve out the foam in the place where the attachment bolt will go through the wing. These cavities will be filled with the epoxy-microballoon mixture to form a hard point for the bolt.
Carve out small cavities between the skins of the aileron/flap in places where the control horns will be installed. You may want to mark the exact location of the control horns by drawing an imaginary straight line from the servo arm to the hinge line. If the control horn ends up being a little off center in relation to the servo arm, the pushrod will be angled.
Mix a small batch of 10-15min epoxy and micro-balloons with the consistency of mayonnaise. Fill the cavities with the mixture, one at a time. Let the epoxy completely harden before handling the panels.
Tape the two wing panels with a clear scotch tape on the bottom of the joint line. This is the time when you can easily check the dihedral angle of the wing and correct it if necessary. If the deviation from the desired angle is small, do not worry about sanding the bevels. You can simply increase or decrease the force when gluing the panels together and allow the epoxy-microballoon mixture to fill the microscopic gap at the joint line. Note the black marks on the bottom of the wing showing the location of the servo wire channels.
Mix another batch of 10-15min epoxy and micro-balloons with the consistency of mayonnaise. Open the taped wing panels and fill the bolt cavity and cover the joint with the mixture. Close the joint and squeeze the excess epoxy out of the joint. You can either wipe off the excess epoxy carefully with a paper towel, or leave it on the joint and then later break it off with a flat X-acto knife. Put the wing between two tables or chairs and load up the joint to apply some pressure while the epoxy sets.
Clean the joint off the hardened epoxy being very careful not to damage the area around the joint. Refrain from applying any pressure to the wing surface when cleaning the joint - you will create visible dents if you do. Sand the skin along the joint line to remove the shine. Sand the joint line also if you have a small bump there.
Prepare 2 strips of fiberglass about 40mm wide (kevlar is shown on the photo, but fiberglass is supplied with the kit currently as it is much easier to work with and the strength is sufficient). Apply the strips to the joint by first lightly spraying them with 3M77. Overlap the top and bottom strips at the leading edge, and simply let them run out at the trailing edge. Wet out the strips with either thin laminating epoxy or thin odorless CA glue. Make sure to use a good quality glue (fresh), otherwise it may not wet out the fiberglass very well and you will end up with dry spots that cannot be saturated with glue later. Trim off the excess material at the traling edge after the glue sets.
Place the wing into the fuselage saddle, make sure it is right in the middle and square to the centerline. Mark the location of the holes in the fuselage bulkhead on the wing's leading edge.
Make two holes at the marked locations by twisting an X-acto knife. Sharpen the ends of the two 0.125" carbon rod pieces. Carefully insert them into the foam, while twisting them. Leave about 10-15mm sticking out. Pull out the carbon pegs, and then re-insert them with foam safe CA glue or epoxy.
Check the alignment of the wing pegs with the holes in the fuselage bulkhead. Enlarge the holes in the required direction using a small round file.
Drill the hole in the wing, then place the wing into the fuselage saddle and drill the hole in the fuselage deck. Use a smaller diameter drill bit first suitable for tapping the 8-32 thread. Tap the thread in the fuselage deck. Soak the thread with thin CA and let it set on its own without using the CA accelerator, to allow for more penetration into the wood. Re-tap the thread after the glue is completely set. Enlarge the hole in the wing for the 8-32 bolt. Cut the nylon bolt to the proper length before attaching the wing.
Prepare the wing servos by cutting off the servo leads and soldering the supplied thin gauge servo wire to them. The tabs were cut off when the servo wells were cut out. The photo shows HS-55 servos. A very good aileron/flaperon servo is D60 from Dymond (http://www.rc-dymond.com) - very thin, powerful and accurate - highly recommended for wing servos.
Make a hole for the servo wires at the marked location. Prepare a thin music wire with a hook on one end for "fishing" the servo wires trough the channels. Insert the music wire through the channel and pull it out at the aileron servo well.
Hook the servo extension wires to the end of the music wire. Pull them through the channel and out the hole in the center of the wing.
Solder the supplied connectors to the servo wires. The photo shows a 4 servo wing. All 4 servos are hooked up to 6 pins, all positive and negative wires are bundled together. For a 2 servo wing you can use either a 4-pin connector or two 3-pin connectors. Make the wire harness connecting the wing to the receiver. You will have to connect and operate the servos when installing the aileron pushrods to make sure that the servos are in neutral position.
Drill the holes for the aileron control horns using a 1/8" drill bit. Do not drill through the top skin, although if you do, it's not critical. Cut one side of the nylon control horn and glue it in the hole with CA.
Prepare 2 aileron pushrods (4 in the case of a 4 servo wing) using 0.050" carbon rods and Z-bend ends from a soft steel wire (paper clip wire). Use small pieces of heat shrink tubing for connecting the wire ends to the carbon rod. Apply a drop of CA first, slide the heat shrink tubing over the wire, and heat the tubing with a soldering iron while the CA is still fresh. Leave one end of the pudhrods infinished.
Tape the aileron at the edge to the wing root to keep it in neutral position. Insert the finished end of the pushrod into the servo arm. Make sure the servo is in neutral. Insert the second wire end into the control horn. Slide the heat shrink tubing onto the carbon rod. Apply a drop of CA, join the carbon rod with the wire end, slide the tubing over the wire end, and shrink it with a hot soldering iron.
The finished pushrod is not adjustable. It is imperative that both the servo and the aileron are in neutral when assembling the pushrod, and the radio has zero trim settings on all applicable channels. All trim adjustments will have to be made via the electronic trim on your radio.

Tape the servos in the wells with a scotch tape. Drill the wing tip for the throwing peg through the carbon spar, and glue the peg (carbon tube) with a foam safe CA. Your wing is ready for flight tests.