It’s been a busy week. The two upper main spars are essentially complete. Spar caps, stiffeners, and all of the filler and reinforcing blocks are assembled. The only thing not done are the outboard ends, where the tapered pieces for the wingtip bow attachment need to be assembled. The two lower main spars are under construction now. Both have the caps and web glued, and one has the stiffeners on one side. I’m planning to finish as much as I can today on the main spars, and hopefully get at least one of the rear spars glued up.
It’s been a real joy working in a place where there’s plenty of room to work. The availability of a large number of bar clamps – in addition to the 40 or so spring clamps I have – really helps as well. I took the day off work yesterday and was able to get over there once in the morning to set up a spar, then again in the afternoon to take that one off of the jig and glue up the next one.
Stu is anxious to get enough pieces built to start getting wings assembled so they look like wings — I can’t say I’m not in agreement. I was a little tempted to build a rear spar after the first main so we could assemble one complete wing, but I’m convinced that this way is a lot more efficient. For one thing, after the first spar we’ve both figured out enough ways to make the process better that each spar is taking less time than the one before. Just as an example, my process for getting epoxy into the grooves in the main spar caps has evolved and gotten much more efficient with each spar. It’s almost a shame there aren’t any more to do. On the last couple I would get some glue on the long edge of a popsicle stick and use that to spread it into the groove. After doing a foot or so, I’d slowly follow through with an acid brush with the bristles trimmed down to about 1/4″ or so, to make sure it was evenly distributed and get any excess out of the groove. The result was the cleanest glue joints of all the spars.
I’ve been going through T-88 like crazy. Gluing 9 and 10 foot long pieces of wood uses a lot of epoxy, and I know the laminations for the wingtip bows and tail surfaces will use a lot as well. Given the price increases since the last time I bought glue, I think I’ll just order a gallon.