On 2009-07-04, wrote:
On Jul 4, 1:36*am, "DoN. Nichols" wrote:


* * * * Someone else suggested a light dimmer which is typically quite
inexpensive -- and as for motors -- a cheap hand held electric drill
could be clamped onto a shaft in bearings to drive at a lower speed. *
Or -- you could salvage a motor out of a vacuum cleaner or a kitchen
blender or anything else with a DC/universal motor. *(Just look for
brush holders to verify that it is not AC only -- and the holders may
be hidden inside, as is common in cheap hand held electric drills.)


* * * * Enjoy,
* * * * * * * * DoN.

That someone was me. Light dimmers work pretty well. They are a
stiffer source than a variac,

Perhaps stiffer than a Variac rated to match the load, but if
you have a 7A Variac or larger (I've worked with 20A 240V ones) I
challenge you to get stiffer. :-)

and I believe the back emf from the
motor affects when the triac fires.

Hmm ... that could be helpful as feedback.

Another source for universal motors is WeedWackers. I bought one at a
garage sale recently for $5.

O.K. That might be about the HP range needed for the Taig.

Enjoy,
DoN.

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