Re: X axis spring back on vice squaring ?
Interesting! I wonder if you might shed more light on the problem if you put something on each end of the table and trammed them to see if the problem was still there when the table was at the extremes. If you have a second DTI or even a indicator, maybe setting it up to read the top of your vise jaw as you did your test may narrow your search.
What I find interesting is the slo-mo speed at which the dial comes back to zero. It sure looks like parts floating on a oil film that slowly ebbs away...but a typical oil film wouldn't be .002 thick would it?
Make sure the saddle is tight and not wiggling. A ballnut that's not 100% aligned with the ends could possibly be putting the table in tension.
Good luck and keep us posted, I would love to know the outcome of this bizarre problem.
Stuart
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