Is the thread for a spindle nose mount, or in the operating part that moves the jaws ?

Power operated chucks have fine pitch threads in the part that moves the jaws for a connecting tube running through the spindle to the hydraulic or electric actuator mounted on the back of the spindle.

Nigel B

Possibly a woodworking chuck?

Lots of wood lathes have a 16tpi thread, but usually smaller diameter and not lever operated, which is also less common for this diameter. Perhaps made as part of an engraver general fitting pack where a large diameter might be wanted but minimal force.

Old Mart,

Surely you have heard of screwing a softwood block into the chuck to take an impression of the thread, so much easier to measure later with decent light etc.

Regards Brian

I have done a (small amount) of digging on this, mainly because I have a bit of a "DDR fetish".

Googling the visible model number on the picture above gets several pictorial hits in German, most being obsolete sales listings. Obviously used examples are frequently heavily sawdust encrusted & there are couple that are shown attached to woodworking lathes. This listing includes a picture of the original chuck box, with pictures of turned wooden objects & also a picture of the chuck that I think I can see an adapter bush fitted into the back of the chuck – the faceplate alongside has a much smaller mounting thread.

So it may be that the M32x1.5 thread is provided to make the chuck a "universal" item, being adapted to fit the lathe spindle nose with a bush (M32z1.5 outside, lathe spindle thread inside) as required.

Nigel B.

To see the pictures, click on the greyed-out image that says "geloescht" & the original pictures appear. Scroll through to get to the chuck packaging etc.

Edited By mgnbuk on 14/02/2023 16:29:57

The only thread that size that I was able to find is the er25 collet nut thread, not quite the best mount for that chuck. 33mm is the closest I could find, but the pitch is much coarser.