On Fri, 21 Nov 2003 04:47:29 +0000, Mark Rand
wrote:

OK, now that rheostats are out of the way...
I had cause to look carefully at the speed controller of a Dremmel when mine
stopped working. The speed controller is a simple variable resistor-diac-triac
circuit AKA a light dimmer!

In other words, get a light dimmer that will handle the current, one sized at
150 watts will do, and that should do the job. The universal motor on a
Dremmel is quite an inductive load and triacs like that sort of load, so you
shouldn't have any problems with it.

HTH

Mark Rand

Quite true. A lamp dimmer will work with any universal motor tool like a
dremel, a drill, router etc, though may not give good speed regulation due
to lack of feedback. A variac will do the same. However you should not use
an electronic speed control on a tool that incorporates one internally.