Author Topic: rheostats-motors  (Read 1142 times)

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Offline gypsyman

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rheostats-motors
« on: February 23, 2009, 08:16:39 AM »
Well, wonder if any of you have an answer to this problem. Using a 14'' chop saw to cut metal, using the standard blades, it get real dusty, and expensive, at $7-$9 a blade.
Picking up steel at the distributer, I noticed he was cutting the metal with a carbide blade. Not as noisy, and alot less dust. So, just had to go order one. Got it in last week. Then I unwrapped it, and seen, 1400, or so rpm only. And the chop saw I have is a 4600rpm motor.
Well, I had a thought, could I plug the saw into a rheostat, start out at full power, and then turn the rheostat down, to lower the rpms. Guy at the local hardware store didn't think this would work. Wouldn't have the torque at that low of an rpm to keep the blade cutting.
Really don't want to go out and buy another chop saw, as the one I have is only 3-4 years old, and the first one I used lasted 11-12 years, so I figure I have 8-9 years left in this one. Any ideas??  gypsyman
We keep trying peace, it usually doesn't work!!Remember(12/7/41)(9/11/01) gypsyman

Offline j104wd

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Re: rheostats-motors
« Reply #1 on: February 23, 2009, 01:19:36 PM »
guy at the store is right. trying to turn that motor that slow and load it up while cutting you will more than likely rasie a commutator segment and will not be able to keep it from eating up brushes. best advice is to suck it up and keep buying abrasive blades. Or find a band saw or a cold saw that is what the guy at the metal place was likely using.