Hi i am new so this may be a simple question. However when I watch videos of setting tool offsets for a cnc milling machine they all show how to set the tool offsets on finish (sides/top) of parts. My question is how to allow for Roughing? If you put a part that is from stock material in a machine and touch off your tools how will you know the finish surface for your finishing tools without re-touching off tools. If I touch off the Z and save the offset, but .010 needs to come off the top of the part with a shell cutter or fly cutter, how can End Mills know the exact top of the part after the fly cutter runs. Is it possible to put rough stock in a machine and have it roughed-in and finished with the same program? I imagine if you have 10,000 parts to run then there must be of way of not having to square-up parts first. I did see a video about using the tool length wear in offsets but don't completely understand it. I want to know the standard way you guys put in rough / oversize material in a vice (against a stop) and do all the roughing and finishing with the same program and how to set the tool lengths and X, Y, offsets to do this. Thank you, and if I am not being clear enough with the question please tell me.