I came up with the idea of the adjust true this afternoon too.
MY chuck is a direct A2-6 mount, but this customer is pulling this in-house and I delivered most all of my tooling to
them last night, and I am trying to help get it going as much as I can. But once I remembered that they don't already have a chuck with an A6 mount on it, the adjust-true came right to mind.
I called Kalamazoo and they just sold their last 12" and would be a while before they had their stock filled again, so then it was on to Buck, and that's the links that I sent this afternoon.
Yes - Shirley I can build the spacer, but not sure if they can or not? Maybe....
But as you say, maybe they can git away with just some really tall jaws, but they would need to be about 5" tall as my jaws are 3" as is. The first cpl of inches of the part - there isn't anything to grab on, so .... Besides, I liked the scroll for the feel as if I clamped it down too hard, I would deform it, and then the bore would be out-of-round when unchucked.
Also - the part is prox 4" D with features beyond that under one jaw, so I don't know if a person can expect to git a serrated jaw to get there (5" out) or not? I don't have much experience with serrated jaws, and so far dis-like them. Also - IDK if a person can find 5" tall soft jaws for an 8" serrated chuck in the first place? And making a few serrated jaws yourself would seem to be as much hassle as making the spacer, so IDK what they will doo.
I think this is only prox a 600 RPM job.
Also - they would need roughly 3" of dead air space to git past that probe. An extra .5 or inch aint gunna git there....
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Think Snow Eh!
Ox