In article , frank wrote:

The key problem is the large pulley cannot be cut on the lathe. It will not
fit.

The only other power tool I have to do the work is a mill/rotary table, and
since
I have to set that up to do the work on one pulley, it seems like a good
idea to
just cut all 4.

[ ... ]

My Atlas has a 1/2 hp motor and the Bridgeport has a 1 hp motor. Blowing
through
6061 T6 with not-that-high precision seems to be a function of motor hp and
little
else. The mill wil be quicker.

Do you have a stub arbor for conventional milling cutters (those
for horizontal mills)? If so, what you might be able to do is first cut
a groove to the depth of the pulley's needed 'V' with a standard one,
then take a somewhat wider one, and have it ground to match the profile
of the 'V'. (This will need someone skilled at using a Tool and Cutter
grinder, but will result in pulleys with all 'V' the right shape. (It
will also probably fill the shop floor with chips. :-)

I would be more tempted to use a horizontal miller with the
rotary table -- but that is in part because I *have* such a miller.

Probably the most critical feature would be the design of the
clamping part on the stub arbor -- you run the risk of running into the
next sized step with the hub -- unless you started out with a rather
large milling cutter before modifying it to 'V-groove shape. Be sure to
lock up all axis motions which don't need to move, as this is going to
be asking for chatter with a vertical spindle mill.

Good Luck,
DoN.

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