Brief Description: Work on Center Spar bolt and rivet drilling/alignm
After predrilling the spar webs and spot-marking the spar caps, it was time to place them in relation to the web and each other. While this may not be a real challenge for any other builder, I found myself sweating every dimension and adjustment. After marking the caps, I felt comfortable match drilling the front and back spars together with a #21 bit (for AN-470-AD-5x rivets). This then made the holes in the spar caps bigger than the #40 pre-dilled holes in the webs. I took the spar caps apart and placed them between the webs, with spacers temporarily in place and set the distance between each set. Because everything was in flux, I clamped it all together and then didn't want to move it. I decided to try to dill out the pre-drilled #40 holes in the web to match the caps behind, which is something you should never do. Always back drill through the part that is your final size. The result on my first spar cap was less than wonderful. At that point I stopped for the night, more than a little baffled at how I was going to match the webs to the caps from behind...not to mention how I was going to make my bolts (as yet undrilled) and spacers match and be snug while positioning the front and rear webs in perfect alignment. Excedrin headache #26. There are times when the best thing you can do is get a good night's rest.
