I cut and fit the first diagonals today. That was interesting. I really didn't know what to expect as far as trimming two angles to fit, so I took the first really slow. I was just about to cut the first diagonal and have it die into the first cross tube, but I got looking again. I was just taking the tube centerline and having it line up with the crotch of the cross tube, which makes it pretty easy. But, it doesn't match the plans. So I did a little research and I'm glad I did. I came to the conclusion to follow the drawings. One of the aircraft welding books I have (Aircraft Welding by L.S. Elzea) said to set the tubes and weld according to the drawings because that is the way the engineers determine the load paths. The load paths would change if the centerlines were off. No big deal. I went ahead and fit the tubes and it turned out fine. It was easier than the cross tubes. I fit one end of the tube, then fit the other end to the longeron. Then, I trimmed the end of the diagonal to length to fit the next cross tube.
I also flattened one side of the 1 inch cross tubes to accommodate the landing gear reinforcements. I had a ball peen hammer that was a little rough, so I smoothed the face on the vertical belt sander and polished the face with an orbital sander so it wouldn't damage the tubing. I tried one and it worked out fine. I'll get the others done and refit them next time.
