I don't, but recognize that I should. After cutting all pieces for a quilt a couple of years ago, I couldn't figure out why it wasn't coming together as it should. Went back and checked all my measurements, they were all as directed. That's when I realized there was an error in the pattern. It all went back in the box; someday I'll have to either try to figure out how to salvage it, or put the cut pieces in my scraps bin and give up.