Stephan's Sonex #1627 Builder's Log

I had some time during lunch today to rivet the elevator root assembly. I figured it was going to be easy and take me only about 15 minutes. Well, it took me the better part of 1.5 hours. It all went well until I couldn't get my pneumatic riveter perpendicular to the part to set the rivet because of the welded parts being in the way. I foolishly tried to pull a rivet with the head of the rivet gun on a slight angle.  The rivet set with one side noticeably up instead of flush with the part. I decided that I was going to use the hand riveter for the other two adjacent rivets instead. I had practiced on a scrap piece before and believed that I could pull a good rivet. Well, the hand pulled rivets were even worse. I obviously need more practice. 

I ended up drilling out the 3 bad rivets. I had to use a wrench to prevent the rivet head from spinning, but in the process, I created bite marks in the part from the jaws of the wrench. I now had to spend time polishing the scratches and straighten the flanges. I decided that I was going to try and use the pneumatic riveter again, as this seems to pull better rivets.

I decided to grind down the tip of the rivet gun so that half of the tip had a slight angle. This allowed me to put the proper force on the rivet head so that it remained flush with the part while pulling the rivet. This worked well for the first rivet, but I had to put a slight bend in the mandral of the other two rivets in order to ensure that the rivet stayed flush with the part. 

I kept the same pressure (about 45 psi) as I was using before, but it took a little longer before the head snapped off. The end results looks fine. Lots of lessons learned today. 

The elevator root assembly was fairly straight forward. The only important thing to note was that the top edges of the left & right root ribs were not twisted.