Bench Buffer RPM's

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SteveHGraham
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Bench Buffer RPM's

Post by SteveHGraham »

I really want a wire wheel on a bench grinder, but since I don't have a buffer, I think I want a buffer with wire on one side and cloth on the other.

When I started looking into buffers, I saw two main schools of thought. One group says go 1800 RPM because 3600 will throw things and kill you. The other school says go 3600. It will work faster, and if you're afraid of the speed, you can use small wheels which reduce the SFM. Also, with high RPM's and small wheels, you can get into little spaces without sacrificing as much speed. Seems to me the high-RPM people make more sense.

Wondering if anyone here has a recommendation.
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Steggy
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Re: Bench Buffer RPM's

Post by Steggy »

SteveHGraham wrote: Sat Mar 16, 2019 11:34 pm I really want a wire wheel on a bench grinder, but since I don't have a buffer, I think I want a buffer with wire on one side and cloth on the other.

When I started looking into buffers, I saw two main schools of thought. One group says go 1800 RPM because 3600 will throw things and kill you. The other school says go 3600. It will work faster, and if you're afraid of the speed, you can use small wheels which reduce the SFM. Also, with high RPM's and small wheels, you can get into little spaces without sacrificing as much speed. Seems to me the high-RPM people make more sense.

Wondering if anyone here has a recommendation.
I run mine at 1800 (actually, 1750 or thereabouts). My experience with wire wheels spinning at 3600 is when the wheel grabs the piece—always a matter of when, not if—the velocity at which it will be hurled will be hazardous to both your person and nearby light fixtures, etc.

The other consideration is the faster-spinning wire wheel will tend to shed wires more often, which aside from reducing the life of the wheel, gets really annoying when your arms are being pelted with wires.

As for how rapidly the wire wheel will do the job, it comes down to linear velocity, not angular velocity. A large-diameter wheel turning more slowly is just as effective as a smaller wheel turning more rapidly. If I need to get into tight places, I use a knotted, cup-shape wheel in my small angle grinder.

Fabric buffing wheels should not be run at 3600. The fabric becomes too stiff from centrifugal force, causing it to abrade rather than polish. Buffing is generally a low-speed operation, 1200 RPM-or-so being the ideal speed.
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SteveHGraham
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Re: Bench Buffer RPM's

Post by SteveHGraham »

Are people really being struck by objects while standing to the side of the wheel?
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tornitore45
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Re: Bench Buffer RPM's

Post by tornitore45 »

If the flung piece misses the operator it may hit the wife car and start an endless shaming process. Luckily some people are immune to shame.
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SteveHGraham
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Re: Bench Buffer RPM's

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I can put a disassembled motorcycle engine on the kitchen table if I feel like it. If anything bad happens here, I have only myself to answer to, and I'm very lenient.
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Re: Bench Buffer RPM's

Post by spro »

There is cross contamination of ferrous rust to the buffer wheel. It may show up on buffed aluminum.
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Re: Bench Buffer RPM's

Post by SteveM »

I have a VERY large buffer. It can take wheels up to maybe 20" in diameter, although at only 1/2 hp, I'm not sure it could handle that.
HobartBuffer.jpg
It's made by Hobart, I believe the same company that makes the deli slicers.

It runs at 1800rpm. I have wheels up to 8" in diameter and I can tell you that, with a 6" or 8" wheel at that speed, it's smearing the compound and not doing a good job of buffing.

I'm going to get some 12" wheels for it, which should solve that problem.

I'm not sure I would want to put a 12" wire wheel on it, as that just sounds too scary.

I think a having both an 1800 rpm and a 3600 rpm buffer would be the best choice. My dad had a buffer that had two speeds, but used buffers on craigslist are cheap (I got this one for $10), so there's no reason not to have more than one, unless you don't have the space.

Steve
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Re: Bench Buffer RPM's

Post by SteveM »

SteveHGraham wrote: Sun Mar 17, 2019 6:41 pm I can put a disassembled motorcycle engine on the kitchen table if I feel like it. If anything bad happens here, I have only myself to answer to, and I'm very lenient.
My friend Al had his Ferrarri 308 engine disassembled on the dining room table.

That got come comments from his girlfriend.

He said "But I put some cardboard under them", to which his girlfriend replied "Yea, to protect the engine from the table!".

Steve
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SteveHGraham
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Re: Bench Buffer RPM's

Post by SteveHGraham »

RE buffers going cheap on Craigslist, have you looked at the used tool market lately? It's a desert. Go look for used Baldor bench grinders on Ebay. There used to be dozens. They're gone. It's true of other tools, too.

If people are buying up used tools, business must be good. Looks like the economy is better than the press is letting on.
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Re: Bench Buffer RPM's

Post by spro »

The "press" sucks. The agenda is driving force and that is clear.
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