Hot bearings

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edwardsjc
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Joined: Mon 12 Mar , 2012 13:17 pm

Hot bearings

Post by edwardsjc » Tue 16 Jun , 2015 22:04 pm

Hi

I've been using my new Novamill for the children's school project ( engraving brass key rings). It's been running flat out for a couple of hours , but the spindle bearings have got so hot I could barely touch the casting. Most of the grease has migrated south and now the bearings sound less than perfect.

This thread ( viewtopic.php?f=45&t=712) suggests SKF 7208 B bearings should be used, although I've not managed to find any genuine SKF ones with this exact part no. Are some of the other SKF bearings in the 7208B series with different suffix characters suitable ?

Thanks

Jason

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Re: Hot bearings

Post by TDIPower » Tue 16 Jun , 2015 22:31 pm

From reading that post I see it as FAG not SKF but either way...
http://simplybearings.co.uk/shop/advanc ... ords=7208b


Pete

edwardsjc
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Re: Hot bearings

Post by edwardsjc » Wed 17 Jun , 2015 19:12 pm

Hi Pete

Thanks for the link. I had already found that particular site, although I was put off by the lack of a definite manufacturer for that bearing. I think the banner just said 'FAG and other leading brands'.

I've emailed them and they've indicated they will supply FAG or SKF bearings rather than unbranded ones so I've ordered the replacements.

Next question - How do they come out ? I can see the key needs to be removed and that the spindle will come out of the bottom. The top bearing clearly has to come out of the top, and looking at the drawings, the bottom one should come out underneath. Is there a recognised procedure or sequence to extract them and more importantly to fit the new ones ?

Thanks

Jason

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Re: Hot bearings

Post by TDIPower » Wed 17 Jun , 2015 20:05 pm

Ive used Simply for lots of bearings, never had a problem. I always just pick the manufacture I want from the list it shows up. Always arrive in a day or two.

Never done the bearings on a machine so can't help there sorry.

Pete

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Re: Hot bearings

Post by angel-tech » Thu 18 Jun , 2015 1:22 am

it pays to spend more than you want to on bearings, cheap ones don't last.

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