Chuck lock

[WoofityParticipant @woofity]

There have been comments in recent threads about the risk of chucks becoming unscrewed when running the lathe in reverse; I thought that this idea may be of use to anyone else whose lathe has a similar configuration spindle

I have a twenty-odd year old far eastern lathe (Lin Huan) which I bought new . It came with all the normal accessories, and the faceplate has a split collar on it which when tightened, prevents it from unscrewing.

One diameter fits the boss on the back the chucks” backplates ( I”ve machined them all to the same diameter) and the other, the end of the spindle next to the thread.

Thanks to all for the useful and entertaining postings to the forum.

Peter

[WoofityParticipant @woofity]

Stop lathe chuck from unscrewing

[joegibParticipant @joegib]

Very nice implementation of a technique that deserves to be better known. This device was mentioned some years ago over on the Practical Machinist website. There was some discussion about whether the chuck backplate collar also ought to be split to allow the auxiliary collar to transmit proper compression to the spindle register. The answer was no — if the backplate collar is well fitted to the register, the auxiliary split collar applies quite sufficient compression to lock the chuck.

 

Indeed, the technique was used by either Weiler or Schaublin (I can’t remember which) for their threaded-note lathes so it has a respectable provenance. Obviously, though, the backplate collar needs to be accessible so the device can’t be used with chucks internally threaded to screw right up to the spindle flange.

 

Joe

Edited By joegib on 24/01/2011 09:17:24

[Ian S CParticipant @iansc]

Joe, just reading your last paragraph, I think a similar collar could be fitted to an internally threaded chuck, by bolting it directly to the back of the chuck, it would be a permanant attachment.

Must look into this it might be rather handy. Ian S C

[Author]

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