Air tight, double sealed bearings?

[duncanh]

I want to build a vacuum chuck and need an airtight bearing. Does anyone know where I can get one in the UK?
I've tried rubber sealed (not sold a double sealed or airtight) ones but the vacuum just pulls the lube and air through them.

Thanks

Duncan

 

[Daven]

Not sure if they sell airtight but simplybearings.co.uk may be worth trying - just bought new bearings for my bandsaw from them - good price and quick to deliver!

Dave

 

[inaspin]

Hi Duncan

Did you ever have any luck with finding a bearing, I am trying to build myself a vac chuck as you were but cannot get a seal on the bearing.
The one i have is metal sealed if i block the whole and blow through it offers no resistance at all, getting very frustrated with it now.

Or does anyone else have any suggestions, i have contacted several bearing specialists and when i ask for an air tight bearing they al say they have never heard of one.

Hope someone can help

Berns

 

[Tony Spear]

Hi Duncan

i have contacted several bearing specialists and when i ask for an air tight bearing they al say they have never heard of one.

Hope someone can help

Berns

I think you're going to struggle there. The "seals" on bearings are mainly there to stop crud getting in and wrecking the bearing.

If you want to stop air (or fluid) getting through a bearing you need some sort of shaft seal, which is a whole different area of technology in itself.

 

[duncanh]

I got some double sealed bearings from drivedesignltd.co.uk
I don't have the specs to hand and their website is being rebuilt so can't search for the ones I bought, but as Tony said - you can't get air tight bearings.
The ones I have work well

 

[Tony Spear]

Berns, you could try talking to a shaft seal specialist e.g. Sealmasters:

http://www.sealmasters.co.uk/rotary.htm

Let us know how you get on.

 

[inaspin]

Thanks for your replies and suggestions, I have gone very high tech with this now it involves a rubber glove and a wine cork .

I have ordered two sealed bearings from a company in scotland as a back up if this fails, i will keep plodding away at it. I have had a thought about marine bearings would a water tight bearing also be air tight? its just a thought surely they make a water tight for outboard motors prop shafts things like that.

Berns

 

[Tony Spear]

Berns,

I was thinking about this and came to the conclusion that it must be possible to what you want, maybe meant for small two stroke engines, cheap pumps, cheap compressors (or even cheap vacuum pumps!) etc.etc.

Then I found this:

http://www.bobchapman.co.uk/_1__Making_ ... _chuck.pdf

So it looks as though you can get what you need if you ask the right questions!

I'm embarrassed to say that as a pumping specialist I should have realised that there must be something like that on the market, but in my defence I should point out that I used to be involved with much bigger machines than what you're looking at!

 

[inaspin]

Hi Tony

Yes i have seen this in fact it was this that gave me hope especial the double sealed bearing bit that is why i have ordered some, and don't feel embarrassed i probably didn't make it clear enough as to what i actually needed, and i am very grateful of you input.
Regards
Berns