Found a dodgy collet (.001" runout) at work today from our Mikron hobbing machines and I'm trying to find some replacements.

We had some made several years ago (this is one of them), but we've had other issues with them as well with the threads being too tight in the drawbar so if we can just buy some off the shelf it would be preferable.

All the key dimensions say it's a W20 (diameters, lengths, nose taper, keyway, 45/5 degree buttress thread) except the thread pitch; standard W20 is 1.667mm (1 2/3, yeah, it's weird), ours are 2mm pitch. I'm confident nothing has been modified because we have factory collets with the same thread and 3 machines can't all be wrong.

Is this a standard collet of some description, or did Mikron decide that they wanted to be just different enough to make life difficult?

We could make new drawbars to suit normal W20s, but that's not being considered as a practical option at this point unless we absolutely have to (and we don't).


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