Bearing RPM

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Lonnie B
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Joined: Thu Sep 05, 2013 7:42 pm

Bearing RPM

Post by Lonnie B » Fri Oct 18, 2013 11:10 pm

Hi Guys I have a question. I ordered a couple of sealed bearings to complete my homemade thickness sander. Now they did not specify a limit to the RPM's for the Bearings. My plans call for an RPM of about 3600 rpm. My motor is a 3/4 hp 3450 rpm. So I was looking to kick the speed up just a little. This I can do with the pulleys of course. Is there a limit I should stay under for the sake of the Bearings?

Dave Bagwill
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Re: Bearing RPM's

Post by Dave Bagwill » Fri Oct 18, 2013 11:55 pm

I have absolutely no idea, but I didn't want you to go without an answer, as if we were ignoring you. We are not. At least I'm not. Whatever LOL
-Under permanent construction

peter havriluk
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Re: Bearing RPM's

Post by peter havriluk » Sat Oct 19, 2013 1:01 am

Have you spoken with the bearing vendor about the bearings' tolerance for rpm?
Peter Havriluk

Herman
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Re: Bearing RPM's

Post by Herman » Sat Oct 19, 2013 1:29 am

Lonnie, Every quality bearing has a code on the side. This refers to an industrial standard that includes form, sizes, clearance and also max revs.

Probably yours can be found on the net.

ken cierp
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Re: Bearing RPM's

Post by ken cierp » Sat Oct 19, 2013 9:03 am

You need to reduce the RPM not increase! Drum sanders normally run at about 1750 and the low power ones have at least 1.5 HP. I'd use a reducer pulley -- you'll get more torque and the motor won't stall as easily. Spinning the drum faster will only lead to more heat and clogging of the abrasive. With a really low power motor (3/4 HP) I am sure you need to feed the work "very, very slowly" and make very shallow passes ------ .$02

Lonnie B
Posts: 542
Joined: Thu Sep 05, 2013 7:42 pm

Re: Bearing RPM

Post by Lonnie B » Sat Oct 19, 2013 10:19 am

Thanks guys. Appreciate your answer Ken. I ordered it off Amazon. So there wasn't any of the info I asked for. So basically I need to reduce the speed by half ? That should be easily enough done. Thanks guys

Ray Ussery
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Joined: Wed Dec 21, 2011 12:51 am

Re: Bearing RPM

Post by Ray Ussery » Sat Oct 19, 2013 3:12 pm

Lonnie, this may be of help to you, very easy way to determine what to use where and what will "Fit"...I've used it a lot over the years.

Scroll down about half was there's a pulley and speed calculator.

http://www.culvermotor.com/Engineering- ... lator.html

Ray

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