That's a pretty good deal if they are in excellent shape. I find 6" a bit tricky to get the right feel when checking parts. I can't imagine trying to hold a 54" pair and getting a good feel.![]()
I do see he has a base to clamp the mics in though, but it would still be tough I think to even hold the part to check it in the mics.

saw them used used every day in the last machine shop i worked in.
one building was dedicated to roll machining, OD grinding, and machining crane cable drums for steel mills, as well as a heat treat dept, weld shop, and an old converted lathe that ran an automatic submerged arc wire feeder to overlay (build up) worn out roll bodies.
the largest lathe we had was 30' bedways, 60" chuck.
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