Took some time this evening to do some more rivets on the rear spar, I chose to start at the middle hinge (VS-1011) and then work down. I set the first rivet and it appeared to be a non-ideal set..I marked it for later removal and set the next three on the VS-1011 bracket edge (2 each from the top and bottom brackets). Upon closer inspection, I wasn't happy with the rivets - they all had a clenching tendency. So I drilled them out (you can see the drilled out picture below with what I mean about the rivets, they were all clenched over... Walked away from the parts for a bit and did some research and realized that I was assuming the pneumatic squeezer was mainly on autopilot upon reaching the compression portion of its stroke - couldn't be more wrong. So, I made some changes, namely: 1. Put the parts in my vise so I could use two hands on the squeezer and or squeezer+part. 2. This made it easier to verify my squeezer was normal to my work, I could also feather the trigger in a bit and steer the squeezer's direction to keep it normal 3. Success - SOOOOO much better. Not a bad night overall, drilled out my first rivets of the plane and got 24 of them set.