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Buffer size/speed for brass

Does anyone know the recommended SFPM for buffing brass, or have a recommended combination of horsepower, wheel size and RPM that works well for brass instruments? I would like to buy a professional Baldor buffer and I'm not exact sure what RPM or horsepower motor I should get.

I am polishing various size marine air horns:

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The horns are mostly spun brass, basically identical to the last section of a flugelhorn, though some are cast brass machined all over. I buffed the pair shown at the link above with a surplus 1/2 HP 3450 RPM baldor motor, 6" spiral sewn wheel and Tripoli compound, followed by white compound on a softer wheel. This worked well, but I could have used more surface area on the wheels to get it done faster, but the motor bogged down. I also don't know if I'm better off with slow RPM and large wheels, or high RPM and small wheels. It seems like the former would be best for the outside of the horns, but a small wheel is certainly required for inside the bells.

Any help is greatly appreciated!

Reply to
diaphone
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The Caswell site might have some info that's pertinent.

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Peter

Reply to
Peter Grey

Horespower and bogging down will kill ya. It's amazing how one can bog down what at first seems like enough horsepower when buffing. If you are doing this more than just casually, I'd go for 10" or larger wheels and at least 3 hp. You might get away with 2 hp but you'll appreciate 3 when you have a frustrating mark to buff out and need more pressure (rather than going back to sqare 1).

Although they are chinese, Grizzly has several options on what appear to be pretty darned good buffers. The very long extended spindles and selection of wheels might make these a really good option for something like a brass horn. I would at least consider them if your budget allows. Although I haven't used one, they appear (on the shelf) to be decently built and there are so few things to go wrong with a buffer, it's not as big a "fit and finish" issue as the chinese lathes and similar.

As to speed...if you really want control they have one with a VFD already attached. Spendy but you would get the speed control you want. RPM probably is not that big an issue on brass. With buffing compounds, the problem is heat generation and that would be more an issue with plastics. Every professional buffing set-up I have seen for brass parts run fast as heck and they often use their knees to get more pressure against the wheel.

Koz

Reply to
Koz

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