I have a single-speed SC-160 16" Ryobi scroll saw. I would like to add
a speed control to it. So far my experiments with 2 different types of
speed controls has produced the following:
1) Control from a lapidary machine: scroll saw motor runs at about 15
RPM regardless of the setting on the speed control. The motor normally
turns 1725 RPM.
2) Solid-state light dimmer: Saw does nothing until the dimmer is set
to about half of the control's rotation range. Then it runs at full
speed as the setting is increased.

Is there something available that will give me an infinite speed range
for this saw?

Gary