.0001 is so small, a couple wipes with a scotchbrite pad will change it, depending how you are measuring.I used to grind mold cores for plastic injection, even if the tolerance was 0/plus .0005" it was an incredible pita to nail it,without coolant and 20 year old harig surface grinders etc. i would have to let the piece cool off with a wet towel over it,and then if it was still oversize by like .0003,i would spin the scotchbrite over it and send it out. you cannot get back in there and try to kiss .0003 off there,,when the whell finally sparks out ,you took off .0005" ....ooops.   and when the boss says you are making love to these parts and taking too long?? thats the difference between made in the usa or send it to china, i said send it to china,see what you get then. Now we are fixing the molds made overseas on the cheap,because they are no better and no one wants to pay for nice work .

dave j wrote on Jan 16^th, 2025 at 1:41am:


Dave, got any video of that?

SBoomer wrote on Jan 14^th, 2025 at 7:14pm:

I have a small shop out in my barn. A mill and a lathe. Nothing near as precision as I did in my Job but I just can’t get away from machining. I love it.  The tenth part of my career was kind of boring to me. I love throwing chips. Not grinding dust

I think you’ll find most of your equipment gets smaller when it’s colder out. Empirical Observation #3

In the fine woodworking business .010" is called a whisker (red), .001" is called a whisper and a 
.0001" is called a concept.  Almost none of which are achievable 

Rick