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Moseley 6mm Lathe - Need Collets!


Arthurliu82

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Hi All,

Long time listener, first time caller.

I just acquired a 6mm Moseley lathe. Unfortunately, it did not come with any collets. What drew me to the lathe was the cross-slide. I have been interested in getting one for some time and snatched up this package not thinking it could be anything other than 8mm. With that, i am considering keeping it and getting a set of collets to work with. I know there are 6mm lathes made by other manufacturers like Lorch and Boley. Are collets for these machines compatible with mine? Or must i find 6mm Moseley collets only?

Hoping you all can help me in my search.

 

thank you!

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I have an old Hardinge catalog that lists a lot of U.S. maker's collets sizes for watchmaker's lathes (Hardinge has always been a major collet maker to this day). For Moseley "6mm" collets (Moseley no1) they list a body diameter of .240", which is 6.096mm. A Geneva collet in their table lists body diameter as .235" or 5.969mm which is about the right clearance for a collet meant for a 6mm bore (slightly small actually). They list a thread of 71TPI diameter .200" for Geneva and 48TPI diameter .208"for Moseley, the thread for Geneva sounds quite fine at a metric pitch of .358mm- I have a Schaublin 6mm here with .70mm pitch.

So, it's almost certain standard-ish 6mm collets will fit the bore, albeit with a bit too much play for my taste. The drawbar will most probably be an issue but that can be changed, but that's easier said than done. What's really an issue is that the conical portion on the Moseley is 25 degrees, where Geneva (normal) is 20 degrees, same as most 8mm lathes. 

You are in my opinion far better off setting this machine aside as a beautiful curiosity, and finding a decent 8mm lathe. Try not to get a Moseley 8mm with the conoidal bore- these take specific collets with a smooth curve instead of an angle on the collet head and those collets are quite hard to find too!

Edited by nickelsilver
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