Used the C-Frame dimpler for the first time, dimpled the skin for the left stab. I have already learned a lesson on tools - don't buy cheap ones. One of the things I skimped on was a cheap pop-rivet dimpler from ATS. I wish now I had spent the extra $10 and bought one from Avery or Cleaveland. I had noticed the one from ATS wasn't polished, but didn't realize how much it would mark the skin until I used it. The pop-rivet dimpler is a good tool to use in the skin holes near the leading edge, but use a good one!