"Jim Wilkins" wrote in message ...

"Pete Keillor" wrote in message
...
I'm to the point of turning the drive wheel for the belt grinder I'm
building for my son. It'll be 6061 Al, 6" dia. x 2" wide, running on
a 3/4" keyed shaft, and turn up to 3800 rpm. I figure I'll put a
setscrew on the key and another at 90 deg., which will require
drilling from the circumference. I can drill holes opposite to help
balance.

Any suggestions on how to balance this for a hobbyist? I'm not buying
a balancer, but could build something. Or just spin it up and see how
it does? Thanks.

Pete Keillor

If you haven't already cut the shaft to length you could turn the
other end to 1/4" and spin the shaft and pulley with a fast drill, a
variable speed one to accelerate it slowly and carefully. If the shaft
is long enough the pulley will rotate smoothly around the combined
center of gravity of it and its end of the shaft. You could carefully
touch a laundry marker to the shaft to mark the light, high side and
feel the amount of vibration.

-jsw

================================================== ========
[Ed]

One-plane (static) balancing is generally considered plenty for this type of
job:

http://www.mpta.org/MPTA%20B2c%202011.pdf

(page 4)

That's just a knife-blade job, as I described. Make sure the knife blades
are DEAD level. The back sides of two hacksaw blades should be plenty
sensitive. Just stroke them with a stone or some wet-dry to make sure
they're smooth.

--
Ed Huntress