Thread: Need Low RPM Motors

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Hey guys-
I need 3 low RPM motors. I'm looking for something in the range of 3-8rpm if possible. Any faster won't work. I need one of the motors with a decent amount of torque (to run an axworthy rig)- the others not as much. The other 2, to give an example, are replacing reindeer motors which don't have ENOUGH torque (they reverse direction when they hit too much torque). Times short, I don't have time for these set backs. Any suggestions on where to get there?
Thanks

Just a suggestion:

After having many low RPM AC gear motors bite the dust over the years, I now use wiper motors with PWM DC speed controls. Wiper motors are plentiful, inexpensive and have great torque. With a 5 amp PWM speed control you are only looking around $35 per setup. You can then dial-in the exact speed you require without loosing any torque.

Now I'm interested.
Maybe this may sound like a stupid question but, what is a "PWM DC speed control" and where can I get one?

No, I second that question! I'd love to know where to get one as well...

Found this-
Harbor Freight Tools - Quality Tools at the Lowest Prices

But am being told that they lower the torque... so if I need, say, 6rpm- if the math is the same, I'd only be getting about 10% of the motor's torque by dropping the speed down to that.

Originally Posted by Specter

Found this-
Harbor Freight Tools - Quality Tools at the Lowest Prices

But am being told that they lower the torque... so if I need, say, 6rpm- if the math is the same, I'd only be getting about 10% of the motor's torque by dropping the speed down to that.

Yes, you'll loose the torque with that one, it's made for a high speed motor (router) where torque is not critical.

PWM (Pulse Width Modulation) type speed controls allow speed control without sacrificing torque basically by pulsing the motor on/off very quickly.

Better to get one like this:

http://cgi.ebay.com/DC-Motor-Speed-Control-HHO-PWM-12V-24V-15A-Max_W0QQitemZ130259397550QQcmdZViewItem?hash=item1 30259397550&_trkparms=72%3A1205|39%3A1|66%3A2|65%3 A12|240%3A1318&_trksid=p3286.c0.m14

Put it in a a plastic project box (Radio Shack), wire it up to a 12 volt power source (old PC power supply or wall wart) and go.
I generally use 12 volt 1 to 2 amp wall warts for mine.

Gotcha- thanks!

Found this one...
QKits Electronic Kits: MX033, PWM DC Motor Speed Control Module

so:
$20 for a device to reduce speed and maintain torque
and
about $20 for a cheep motor..

I think that defeats the goal of a cheap, low rpm motor..

I can get a motor from McMaster-Carr
McMaster-Carr
for about $45...

Yeah...but then you don't have infinite control. Remember 0-100% with the PWM. Maybe next year you'll want to use the same motor...only a little faster.