I picked up a rock tumbler power unit today at a yard sale with the
thought of using it to spin a ball mill for other compounds . Problem is
that I think it might spin too fast , and I may need to slow it down . I can
use smaller rollers on the shafts (2 , parallel and both turned by a chain
drive) to slow it some , but might need to lower the input RPM's . Currently
has a 1/3 hp split phase motor turning at 1725 - is there any way to speed
control that motor short of changing the input frequency ? Other choices may
be a smaller motor sprocket , or maybe an inline (planetary?) gear reduction
unit or v belt and jackshaft arrangement . Could also change out to a
universal or DC motor and appropriate control system , or use a 3 speed fan
motor I have on hand . But speed control of the current motor would be the
easiest and cheapest ...

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Snag