You can buy three speed motors for next to nothing on ebay. I scrapped
~300 lbs of them last year because I did not feel like selling them for
$5-10 was worth my time.
Multi speed seems easiest.
I do not think that you should. They are inexpensive. Especially in a
small fractional HP range.
I bought a wood stove. It has a one speed fan on it. Trouble is, it sounds
like a jet taxiing. Is it possible to put a dimmer on the motor, or do I
have to get a three speed motor, and does that convert to $$$$? The
squirrel cage and motor are in one housing, so I'd probably be looking high
and low for another combo like that unless I wanted to make one up out of
sheet metal, which isn't that hard to do. Or maybe I could find an
adaptable squirrel cage and housing. Question is the multi speed or
variable speed motor.
What's the easiest cheapest way to go here? I don't mind fabbing stuff up,
and it's behind the stove, so no one will see it. I just don't like paying
as much as a month's car payment for a specialty motor.
Unfortunately, the induction or split-phase motors on squirrel-cage
blowers do not generally respond well to speed control with a dimmer.
Although it shouldn't work, it sometimes does anyway up to a point,
and it's cheap and easy to try.
If it's that noisy, it just might have a universal motor. If it has
brushes, it's a universal motor. Those respond very well to dimmer
First thing is figure out exactly what kind of motor you have.
Bodine's motor handbook should allow you to identify the motor and
what speed control options you may have.
The permanent split capacitor motors often used on blowers will run
happily on reduced voltage. There's one on the radiator in my office
that I've been operating on half voltage for almost 15 years.
Grainger has lots of choices in inexpensive small blowers and
replacement motors, if that's the route you go.
I'll mess with it when I get back from Vegas. To me, it sounds like air
noise, as it blows a lot of air. Bothersome, though when watching TV. We
made the first fire in it last night, and the blowing air really heated up
the big room it is in. As per iggy's response and others, I don't think
tweaking it or changing it completely out will be a biggie. I can even
mount the motor off of the stove and put a duct to the opening, so that I
can have the motor on a rubber mounted box and not transferring sound
through the stove. Lots of ways to go.
That's why I wonder if it might use a universal motor. Fan or blower
noise is usually a function of speed, and universal motors run at
higher speeds than induction motors. That's why leaf blowers and
shopvacs are so noisy: they're very high speed blowers.
See what you can learn when you get back from Vegas re what sort of
motor it has, dimensions, speed, etc. Another possible solution is to
retrofit it with a DC motor, as perhaps the fan motor from an
automotive radiator fan -- a junkyard item. Those are easy to
speed-control but you'd need a 12VDC source and perhaps a bit of
simple electronics, either an inexpensive commercial motor speed
controller or something you could probably make for under 20 bux if
you're up for a bit of soldering.
Gunner might have some real nice 90-volt DC motors. You might need a
few minutes at the lathe to make a fitting-up adaptor.
Thanks, iggy. The router table you sent me works great. But I think that I
can either rheostat this down or just get a three speed motor for less than
it would cost in time and money to recreate the thing.
Lots of gas water heaters get scrapped every day. The "eductor" fan
on the top of many late model water heaters can be used as a forced
air fan on a woodstove and is generally a lot quieter than what you
Best of all to an RCMer is they are generally FREE!!!!!!!!
Even if it's a single phase squirrel cage motor, PROVIDED
it's a permanent capacitor run (i.e.not split phase or capacitor
start) it may be possible to make some speed reduction with a
lamp dimmer because a fan load is much more forgiving than a
machine tool load.
It's very dependent on both the motor design and the
dimmer type and not all combinations are suitable. However it's a
quick and simple check so it's worth a try.