Measure once, cut twice

I've made a new set of anti-backlash leadscrew nuts for the Beaver milling machine table.
A fixed nut and an adjustable anti-backlash nut.
The fixed nut is 2" long and 1 5/8" diameter . It has a 1" 5tpi ACME thread for the leadscrew and a 1 3/8" 20tpi thread for the adjusting nut.
I machined the bores, cut the threads to fit the leadscrew and adjusting nut all at one setting, verified the fits to be as near perfect as I could get and then mounted it on a mandrel to trim the OD to the required 1 5/8" diameter to be a snug fit in the housing.
Take 100 thou off the diameter, measure 1.724. Take 101 thou of the diameter to reach final size...
Oh Schidt. I now have 1.623" and a sloppy fit where it should be a snug fit.
Time to start again...
Mark Rand RTFM
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If it's solid bronze maybe you could just coat it with hard solder.
jsw
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What about a knurling it........ Bob
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Reduce the diameter some more, say 60 or 70 thou and shrink on a bronze sleeve. Turn down to correct size.
John H
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What was you expecting ?1.724 - 101 = 1.623
Dumkoff. <bg>
John S.
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On Thu, 11 Aug 2011 00:59:18 -0700 (PDT), John S

The Hardinge seems to take off pretty well exactly what I tell it to, but it isn't very good at pointing out my arithmetic mistakes before the cut. :-(
I'm going to make another nut because bushing this one isn't practical (it's cast iron and I don't want to loose too much meat off it). Loctite isn't preferred, because I _might_ want to take it apart again.
I can use the undersized one to lap out the variation in the leadscrew threads, 3-4 thou worst case. Once I've mapped them out.
Mark Rand RTFM
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