I finally figured out why my parts kept coming out .015 oversize on the Mazak
I was running a batch of 200 aluminum brackets on the Mazak last Tuesday and every tenth part was coming out about .015 oversize, so I pulled the tool holder and found a chip welded to the seat that I kept missing with the air gun. I switched to a small mirror and a pick to check the taper before every tool change, and the next 80 parts held within .002 all afternoon. Do you all have a set routine for checking tool seats, or do you just eyeball it and hope for the best?