John Martin wrote:

The wider the slit, the greater the collapse. So it will lock on a
shaft that is considerably undersize. Not every use of these collars
involves shafts ground to bearing fits.

But if you collapse it to far, it will be permanently bent. Also, you
can't collapse it more than the gap on the side with the screw is. :-)

I really don't think that the key slot was made with much thinking.
Just think about the manufacturing-process:
You have a thick-walled tube, cut to length, drill and tap for locking
screw, then slit the open end _and_ cut the groove in one pass.
As that thing looks, they had to broach the groove as a further step. Or
are such tubes (drawn, with key slot) readily available?


Nick


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