Re: A big ol' chunk of delrin

"Snag"  wrote in message news:vu6eh7$33smg$1@dont-email.me...
   It's definitely an 8 TPI leadscrew , moves the table .125"/revolution
plus/minus a few tenths . OD is within a few thousandths of 15/16" .
Tell me more about this imperial acme thread ... this machine is a copy
of the RF45 , made in China in 2001 . I got it new IIRC in '02 or '03 .
I've made a lot of stuff with this machine .
--
Snag
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I used two import mills with 8 TPI leadscrews and slowly learned to adapt to counting 125. 250 375 500 625 750 875 1000, then adding the dial reading. Had they been mine I would have tried hard to convert to 10 TPI, even if it meant 3/4-10 all-thread like I used to repair my surface grinder.
https://www.grainger.com/product/5DPX7?
High accuracy isn't essential when working for yourself because you can match-drill or otherwise fit the second part to the first. Hand-fitted British shotguns and double rifles are a good example, the fit is super precise but not interchangeable. Before mass production everything precise was made that way. I've used the hand fitting process to improve heatsink transfer.
https://woodworkersinstitute.com/the-art-of-smoke-fitting/
A candle works if you put the metal into the flame.
In WW2 US firms took on production of the Merlin engine and Bofors autocannon, and found that both had been designed with loose tolerances that required expert hand fitting.
https://theaviationgeekclub.com/the-story-of-when-ford-uk-refused-to-build-rolls-royce-merlin-engines-because-the-tolerances-rolls-royce-allowed-were-looser-than-ford-was-willing-to-work-with/
Henry Ford originally fixed watches, planned to mass produce them, and understood high precision manufacture.
A mechanical engineer I knew had converted John Browning's dimensions for the .50 BMG from 128ths of an inch to decimals.