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Old 09-27-2011 | 11:25 PM
  #20  
JeffinTD
 
Joined: Apr 2011
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From: The Dalles, OR
Default RE: 12' Telemaster- gonna need help

Thanks for the positive feedback. I've been eyeballing AMR as a future project, too (the Monster Stick). It looks like their stuff is designed to interlock, where the Tele seems more traditional construction.

The build board is just a couple of doors joined below with extruded angle aluminum, and topped off with 1/2 inch foam insulation (Corning, I think). The foam comes with a layer of thin plastic film lightly bonded to one side. 3M spray glue will eat the foam, so just put the side with the plastic film down. It would be nice if it were a bit stiffer, but it is cheap and easy to change.

Anyway, I didn't get as far as I had hoped today. I got up at the crack of noon (I work swing shift, and the older I get the harder it is to flip my sleep schedule on days off), and also gluing up all those laminates took me longer than I thought. Since they are critical (spars) I really took my time and paid attention to make sure they were free of voids and straight. I also used a woodpecker to perforate the surfaces a bit. Personal preference, but I think it lets the glue soak in and grip more of the wood. Having seen things break where it looked like the glue held but it pulled a "skin" of balsa off, I thought it couldn't hurt.



It also dawned on me that I should take a break to let the glue set on some of those before doing the rest, as too many lead weights might buckle or break my table. Pizza and a beer, and glued up the rest.



Clamping a board on the disk sander made really accurate splice angles. Trying to use the miter that came with it didn't work well because it had some slop, and also is a fair bit away from the disk at that angle. If the stick has a bit of curve, it would mess up the angle that way.

The only down side to that method: Balsa Boogers.

One thing had me confused. The directions list 3 six foot sticks you need to build for each wing panel, including (2) 3/4x3/4 from 3/8x3/4 sticks, but there aren't 8 pieces of 36" 3/8x3/4... Then it dawned on me, these are for the leading edge (a piece of angle stock gets glued to the front during wing construction). I went to public school, but even I figured out there is only 1 leading edge on each wing panel.

Another thing I ran into- when I set the angle for the splices I made sure it would leave the finished sticks at least as long as shown in the plan, but I didn't take into account the other side of the laminate would have two splices. Derp, musta skipped the spar splicing class in public school.

I think they are still long enough, but if not I can always add a little make-up piece to that side of the laminate, on the wingtip end where stress is low. Actually, I may change the wingtip anyway. This kit makes adding custom touches easy.

I then built the forward and aft box beams that go in the center section.



They are plywood with hardwood square stock spacers, assembled with epoxy. Plywood joiners get epoxied to the forward and rear spars on the wing, the ends of which fit into these box beams. Another hardwood block will go on the front of the forward box beam and on the back of the aft box beam, to be threaded to accept 1/4x20 bolts. Another piece of hardwood goes on the rear of the front box beam and the front of the rear box beam, each anchored with 3 hardwood gussets, and those are drilled for the 1/4x20 bolts that hold the center section to the top of the fuse. The bottom center of the center section is not sheeted, and the top center of the center section gets a hatch secured by nylon screws into hardwood that gets glued on the box beams.

I can't go farther than building the box beams without rolling out the plans, and I want those laminates to cure fully before I take them off my board, so I'm done on the center section for the night.

The other thing I figured I'd may as well get done is getting the ribs out and organized. They are really well cut, and are marked. Most pretty much fell out, but on a hand full the laser looked to be about 1/32" short of full penetration, so a little cutting was required.

.

I wonder when those computer guided laser cutters will get affordable. I'd like to have one in my garage, not so much for building models, but for the Zombie Apocalypse...

That wraps up day two. Need to order a slim pits style muffler for the DLE55, since the stock muffler will be too wide to fit between the cheeks. (No, not my cheeks, the plane's cheeks ahead of the firewall)