Tri-Q Gear Attach Fitting Lay-Up
- Category: TriQ Plans
- Published: Wednesday, 29 December 2010 00:00
- Written by Scott Swing
- Hits: 5226
Cut 68 pieces of uni 2-1/4" x 11". Cut 68 pieces of bid 2-1/4" x 3-1/4". Cut 68 pieces of bid 2-1/4" x 2-1/4". Wet out 17 plies of uni 2-1/4" x 11" on a piece of paper or plastic, not wax paper. Usually you can wet out two to three layers at a time. Squeege out excess epoxy but make sure not to make it dry.
Paint a coat of epoxy over the attach section of the gear for and aft over the plywood blocks. Peel the 17 plies of uni off the paper and lay it across the gear and down the taped face of the plywood blocks. This should more than cover the surfaces. Now lay-up 17 plys of bid 2-1/4" x 3-1/4" on a piece of paper, squeege excess epoxy, peel off the paper, and apply on top of the uni, and lapped up over the leading edge of the tab. Now lay-up anotheJC 17 p1ys of bid 2-1/4" x 3-1/4" and apply to the trailing edge of the gear on the tab. Your outside lay-up is now done.
Wrap saran wrap over your lay-up and smooth it out. This should be enough to hold everything in place for cure. If it starts to creep more than a little, you should get a small piece of 1/4" plywood and a small "c" clamp and clamp with just enough pressure to hold everything in place. Large "C" clamps will not work because they are too heavy.
After this lay-up has fully cured you should trim or saw the glass tabs down to the plywood blocks. Now, using a 3/8" bit in a drill, drill a hole as close to the center of the 5/8" hole in the jigging block as possible. Now chuck the 1/4" dia. x 10" long steel rod into your drill, insert it from the rear through your 3/8" hole, then screw the 5/8" dia. spot fac-e tool onto the end of the 1/4" rod. Locate the spot face in the 5/8" hole in the plywood jigging block on the forward tab. Drill through slowly so you don't build up a lot of heat and melt it. Drill through all 34 layers of glass. Now, take the tool apart and repeat the procedure on the other tab.
Now chisel the plywood blocks out as well as the bondo that might be left on the gear. Sand the tabs on the insides, and any area where you are going to glass that might need smoothed out. Mix up some flox (small amount) and, using your finger, put some in the corner between the glass tab and the gear. Make a nice radius with your finger so the glass will flow nicely.
Assuming you now have the gear jigged upright, coat the inside faces of the tabs and the gear between them with epoxy. Using the same method as before, lay-up 17 uni 2-1/4" x 10" and apply from tab to tab. Stipple the uni down in the corners against the flox. Next, same as before, wet out 17 layers of bid 2-1/4" x 2-1/4" and lay them on the glass tabs down onto the gear on top of the uni. This is done for both front and rear tabs. These layups should stay just fine.
Now, using the 10" extension and the spot face tool, drill out the holes from both sides, then all the way through from one side to another.
Drill eight (8) to ten (10) 1/8" holes in those aluminum tubes on the top half of them where they will see glass.
Sand the tube so it is dull and rough. Now, insert the tube assemblies with their bushings in place and slide the gear back in place up in the fuselage. Put the AN6-74A bolts through to lock it in place. Now, check to make sure everything lines up and the gear pretty much splits the hole down the center. Scribe some marks on the aluminum tubes on each side of the glass tabs. These will be used to line the tubes up for floxing and glassing. If you are installing the belly board, you might want to work on that for a while to get the board fitted. After you are finished with that, remove the gear and jig it upright so you can permanently attach those aluminum tubes. Remove the tubes, sand the insides of all tabs as well as a two (2) inch stripe between them, and reinsert them using wet flox where the tubes go through the tabs. Get some scrap urethane foam and fill the area under the tube to the gear. There shouldn't be much room under there. You may also use pour in place foam then sand to a smooth transition. Cut four (4) BID big enough to fit over the tubes, up onto the tabs, and onto where you sanded earlier. Use two (2) BID for each side, micro the foam, and glass. After this lay-up cures, trim and sand the transition smooth.