I am currently getting my Sheraton 9A back into use (see thread "Sheraton 9A 1167".

Included in the package is a collet collection that was never sorted-out when the lathe was previously functioning.
The photo shows one of the spindle adapters and a typical collet marked "Hercus No1".

The drawbar was obviously not a Hercus item as its inserted length within the spindle would not engage the collet.
I have machined the handle boss back so that there is now an excess of engagement.
A couple of sleeves were made to adjust the drawbar inserted length to what I think is a desirable engagement with the collet.

The collet thread is 26 tpi on about 11/16 diameter.

My question is:
- how many turns of the drawbar would normally pull the collet into the fully clamped position ?

A derivative question:
- what is the distance between the end of the drawbar and the end of the collet spindle adapter ?

Keep well,
John.

Edit: Having problems inserting the image.
Tried to copy/paste it but that didn't work.
My Linux system has these 'challenges'.
Will work on it as it obviously worked in the past.
John.


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