I tried an expanding mandrel type before choosing to make the other
angled-cut type.
The expanding mandrel was a tapered plug at the end of a section of
all-thread which was pulled into the split mandrel, but it didn't hold very
well, and was fiddly to release, so I made the other, angled-cut type.

The angled-cut type works well with only a moderate amount of torque to
secure it, and the cut line isn't placed at the location of a bearing, but
farther inside the spindle.
I would expect the grip to be spread out over much of the entire length of
the "fastener".. but possibly not.

When I locate a good heavy duty motor (probably PM DC) for the 9x20 lathe,
I'll convert it as I did the other machine, and the hand crank will likely
be reused for something else.

--
WB
..........


"Jim Wilkins" wrote in message
...
On Mar 14, 7:20 am, "Wild_Bill" wrote:
That type of expanding anchor/holding joint was the type I fabricated for
my
9x20 lathe shortly after I started using it.
Someone mentioned what that type of joint is, but I used it because I
remembered it from a bicycle I had.. it was used where the handlebar stem
was held in the fork tube.
...
WB

That type of fitting presses the spindle tube oval, not good at a
bearing.

I'd consider two concentric tubes, the inner one having a taper on the
end that wedges the slit outer one evenly tight against the spindle ID
somewhere far from bearings. It would work like a ball hole gage, but
have an over-center cam instead of a slow-acting screw to operate it.
The tapered cone could be a separate piece that screws on, giving an
easy tension adjustment.

jsw