Bad bearings? Dah Lih circa 1976 Taiwanese

Ha ha, turns out it was left handed but it took a decent wallop and from the pictures you can see why. Must have got plenty of water in there at some stage. So now I'm after some advice on bearings. It has 2 x 7207 with spacer on the bottom and a single 6006 on the top. I don't want to scrimp on quality so if anyone has a good lead on quality bearings, I'm all ears.
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I chose FAG bearings when I rebuilt my spindle and went with sealed angular contact bearings with a P5 (equivalent to ABEC 5 class). These are high quality bearings that require no break in and no ongoing maintenance for the life of the bearings. Since they're sealed, no issues with water getting in, rust or debris/dirt will affect them. It has been less than a year since these went in but I'm still holding under 0.0001" TIR (just checked run out this week). What's more, they are still running fairly cool at high speeds so I'm happy with these bearings.

This is the equivalent bearing that I used but in the 7207 size: http://medias.schaeffler.com/medias/en!hp.ec.br.pr/72..-B-2RS*7207-B-XL-2RS-TVP

For the upper bearing, that simply needs to be a good radial bearing but I again suggest a 2RS (rubber sealed for life on both sides). I like Nachi deep groove bearings for this kind of application and this would be the equivalent of what I used: http://mortonmemorial.org/7260/NACHI-6006-2RS-Bearings-%7C-NACHI-6006-2RS-buy/.

While deep groove bearings are radial bearings, they also handle high axial loads and are a good choice when used as a guide bearing like it would be in your case.

The FAG and Nachi bearings I linked to can be found for good prices on the net.
 
Ha ha, turns out it was left handed

Before putting good bearings in, I'd stamp LH in a few places....
Looks like the load wasn't what killed the spindle bearings, but a lube failure.

If you can find a local merchant for bearings, ask him; lubrication, cages, precision,
load ratings... preload... I'm sure it's all important, but it's beyond me.

There's a spate of counterfeits available 'on the internet'... and even a few stores.
<http://www.bearing-news.com/skf-destroys-15-tons-fake-bearings/>
 
I can't seem to find the sealed ones. Which letter denotes sealed?
 
Before putting good bearings in, I'd stamp LH in a few places....
Looks like the load wasn't what killed the spindle bearings, but a lube failure.

If you can find a local merchant for bearings, ask him; lubrication, cages, precision,
load ratings... preload... I'm sure it's all important, but it's beyond me.

There's a spate of counterfeits available 'on the internet'... and even a few stores.
<http://www.bearing-news.com/skf-destroys-15-tons-fake-bearings/>
Yeah I'll certainly do something to remember but It's a bit hard for stamping.
 
Ha ha, turns out it was left handed but it took a decent wallop and from the pictures you can see why.

Great! It is apart with no major damage. Congrats. Studied and slow is the way to go.

Yeah I'll certainly do something to remember but It's a bit hard for stamping.

How about a dremel type tool and a carbide engraving bit?

-brino
 
Well they were so filthy and scored up
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Has anyone ever seen this felt liner before? I'm guessing if I go for the sealed bearings I should just oil a new one up and insert it back in there?
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Has anyone ever seen this felt liner before? I'm guessing if I go for the sealed bearings I should just oil a new one up and insert it back in there?

If you go with sealed bearings, not sure what purpose a felt liner would serve. I would probably leave it out.
 
I think I'd leave the felt shield in place. That would reduce the chance of contaminates getting to the bearing. Certain coolants including spray mist, can cause sealed bearing seals to become very spongy and eventually leak.
If it was me, I would try to machine a counter bore for a seal in the nut. That's what I did on my Index 645 mill. Of course, I got real smart and overfilled the bearings with grease and wound out blowing the seal out. Now, it oozes out yucky grease mixed with ISO46 oil.
I like the idea of sealed spindle bearings. Definitely something new. I assume, you can mount these in any configuration just like regular 7200 bearings.
 
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