Speed control for Baldor buffer?

[Dad Was A Racer]

I have a Baldor model 410B buffer that is simply too fast and too powerful for the size pieces that I am typically trying to polish, and I would like to slow the motor down with a speed control. Is this possible?

It's a 1.5hp, single phase, 60hz, 115v motor drawing 13.8 amps, so it requires something with a relatively high capacity. I tried one of the cheapo router speed controllers from HFT and it immediately blew the fuse in the controller (of course).

FWIW the motor currently runs at 3600 rpm.

 

[Milton Shaw]

Router speed controls, drop the voltage to make the brush type motor run slower. An induction motor like that requires you to control the frequency (Hertz) to change the speed. That is what a VFD used with a three phase motor does. That is a big buffer so any controller will have to be pretty stout and will be hard to find.

 

[exmaxima1]

No practical solution for a single phase motor.

AFAIK, though, polishing of metal is typically done at SFPM of 5000-7500. Your 3600 rpm polisher should be fine with up to 10-inch wheels. What are you polishing?

 

[metlmunchr]

You can't really do much to control speed on a single phase induction motor. What diameter wheels are you using now? Smaller wheels slow the surface speed which is the equivalent of running the motor slower.

I've got a 2hp 3 phase Baldor buffer but mine is 1800 rpm. Depending on what I'm working on, I use wheels varying from 6" to 12" diameter, and haven't had a need to add a vfd.

 

[isb cornbinder]

I have the Baldor polisher with 3450 rpm. It is fast. Rather than trying to slow the Baldor, I bought a second Baldor with 1750 rpm. This was option one.

 

[metlmunchr]

Yeah, that's an option, but at 700 bucks a pop for Baldor buffers, it sure isn't an economical option.

 

[isb cornbinder]

I got both Baldor polishers off Craigslist. The 3450 was $400 and the 1720 was $50 more. These deals do not come along very often

 

[dogdog]

dependents on the type of 1PH AC motor you have I think on that buffer.. VFD are for 3PH motors if I am not mistaken... the router speed controllers are more for brushed motors not for AC induction motors ... it's basically a triac dimmer...

 

[American Locomotive]

As others mentioned, the easiest solution is to put smaller wheels on it. The surface speed of the wheel scales linearly with diameter. So going from a 12" to a 6" wheel would be the same thing as slowing the motor down from 3500 RPM to 1750 RPM.