Re: Spindle register issue

m. allan noah

I'll buck the conventional wisdom, and state that the register
diameter does not matter at all. The conical face of the thread, and
the flat shoulder behind the register are sufficiently to achieve
kinematic positioning of the chuck.

I daresay the problem is your testing method. Reground jaws is
basically meaningless, unless they were ground on the lathe in
question, properly preloaded, with the diameter set to exactly the
size of the stock you are now holding. Take of the chuck, and put it
back on, and see if it is consistent. That is a true test.


On Thu, Jun 21, 2018 at 8:00 PM, carbure2003 <guycad@...> wrote:
About. a year ago, I bought a 10K spindle on ebay.

As I have not used much the lathe where I fitted the spindle, ( only with collets) I never noticed that the register was under sized. (1.495 in dia), quite likely machined by a previous owner.

I trialed a chuck with freshly re ground jaws on it and it was defenitely off centered by many thou.

Register defenitely has importance when yo want to swap chucks from lathe to lathe and keep chuck accuracy.
Did somebody ever attempt to rebuild a spindle register ? (Register is 1.510 in dia on my other SB)

If yes, how did you proceed? (Welding is not an option)


Guy Cadrin
70s Millionaire Returns with Surprising Prediction

"well, I stand up next to a mountain- and I chop it down with the edge
of my hand"

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