The rivet gun had stopped working about the time I started riveting the left aileron. I disassembled it and found that it had two rivets jammed in it. I followed the instruction book and adjusted the stroke and primed the pump. It works so much better now! I think the stroke must have been off before, as I would sometimes need to pull the trigger more than once to pop a rivet. I had to put a towel over the vent hole due to the excess oil being sprayed out as I used it.