It's finally time to get these wings rigged! I got a couple of helpers to come over and give me a hand this weekend, and we kncoked it out in about six hours. That includes several coffee/pizza/beer breaks, and a quick trip to Home Depot to buy some longer drill bits. Overall the process wasn't too bad.
We started by rolling the fuselage out onto the driveway, lifting it onto a sawhorse, and then leveling it in both directions. Then we slid both wings into the fuselage. It took a little bit of messing around to get them into position. I had to file a tiny bit off of the fuselage side skin on one side for clearance in the spar tunnel, and we loosened a couple of the nuts on the aft spar carry-through to allow the aft spars to fit in a little easier.
Eventually we got both wings installed and I bolted the spars together through the three 1/4" holes that I originally bolted through when I mated the spars. I pinned the aft spars to the carry-through with some temporary 3/16" lynch pins.
With the wings installed enough to support themselves, we set about taking all the measurements that the plans directed before drilling the holes for the pins that will eventually locate and retain the wings in the fuselage. There are essentially four things to measure and/or check: centering the main spars in the fuselage, leveling the wingtips relative to each other, setting the angle of incidence, and checking the wingtip-to-tail distance. Once the spars were mated, everything was spot-on except leveling the wingtips to each other. We used a length of clear tubing taped to the wingtips and filled with water as a giant level to check this measurement. Initially, the right wingtip was about 10mm higher than the left, so we filed down the delrin bumper that the right main spar rested on until both wintips were within about 1mm of each other in height. This took a few iterations, but eventually I think we got it about as perfect as we possibly could.
Next it was time to drill the 1/2" holes that will locate the main spars within the fuselage. This was actually pretty simple; since the main spars already had 1/2" holes drilled through them, all we had to do was insert the provided drill guide into one of the main spar holes, drill front-to-back through the aft spar tunnel with a 3/8" bit, remove the guide, updrill to 1/2", pin that side with a 1/2" pin, and repeat on the other side. Then we re-installed the forward tunnel zee and all the associated brackets, and repeated the whole process drilling from back-to-front. This was where we had to run to the store and get a longer 3/8" bit, since the overall assembly is pretty huge at this point! Eventually we got the whole stack drilled to the final 1/2" size, and installed the big pins that'll hold the wings in.
Next was the aft spar. This was actually more of a pain than the main spars! The carry-through was already cleco'd into the fuselage when we started, and then when we installed the wings we pinned the aft spars to the carry-through with temporary 3/16" pins. The next step was to install the brackets that fixed the carry-through to the sides of the fuselage. In order to do that, we had to clamp the bracket to the carry through with everything in place, which was tricky in the tight space it was in. Then I drilled and cleco'd the brackets to the carry-through and the fuselage side skins. We disassembled and removed the carry-through and brackets, cleco'd them back together on the workbench, and drilled the 3/16" holes from the carry-through into the brackets. Then we re-installed everything, and updrilled the 3/16" holes to 1/4". This was the tricky part, since there wasn't any direct access to this hole to drill it directly. I ended up removing the front half of the aft fuselage floor since it was still only cleco'd on (thankfully), and crawling up into the aft fuselage to drill the holes from back-to-front with an angle adapter on the drill.
With the aft spar holes drilled, the position of the wings was finally set, so we pulled them back off and put them away. Now I can disassemble everything, deburr all the parts, and reassemble for the final riveting!
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