08/16/2018 Horizontal Stabilizer – Finished Riveting Rear Spar (1.5 Hours)

Second day of squeezing rivets. Still unbelievably slow, but I finished riveting the rear spar.

Believe or not, today’s biggest OOPS moment didn’t come from riveting. As you can see from below photos, I marked every piece with a number when matched drilling earlier, based on their actual location on the spar from left to right.  So as long as I cleco them back in the same sequence from left to right, nothing could go wrong, right? Well, as it turned out, when I was riveting and drilling last night, I forgot to put the whole rear spar back to its original orientation. I started tonight with the bottom of the rear spar on top and the top of spar at the bottom. So I placed all the bracket in reversed order on the spar. To make it more embarrassing, it’s in fact very easy to tell the orientation because the bottom of the spar has the central part of the flange trimmed off.

Well, the good news is that the brackets are symmetrical and the holes all lined up pretty well when I put the clecoes and rivets through holes. It’s definitely not a good idea to drill out all the rivets just to reverse the brackets’ order because that will make the rivet hole even larger in the process. I read ahead in the manual and it seems that the mistake won’t affect installing elevator that much as long as each pair of brackets are reasonably lined up. So I decided to leave the brackets as they are.