Used Flange Gaskets

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Jake Wells
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Used Flange Gaskets

Post by Jake Wells »

I have a 10 porthole chamber all with 2.75 cf flanges. The knife edge of the cf flange bites down on the gasket. Could used gaskets also work? I am concerned that the indentation in the gaskets might prevent the flanges from creating a seal.


Could gaskets like these work even if they have an indentation in them?

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Jerry Biehler
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Re: Used Flange Gaskets

Post by Jerry Biehler »

Jake Wells wrote:I have a 10 porthole chamber all with 2.75 cf flanges. The knife edge of the cf flange bites down on the gasket. Could used gaskets also work? I am concerned that the indentation in the gaskets might prevent the flanges from creating a seal.


Could gaskets like these work even if they have an indentation in them?

Nope, 1 use only. Though if you are careful you can get two uses out of them by only squishing them half way.

You can also use square section o-rings in place of the copper seals. They are reusable and are fine as long as you dont need to bake out at high temps or go to UHV levels.
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Richard Hull
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Re: Used Flange Gaskets

Post by Richard Hull »

Sealing up a multi-flanged system can be a real bear, but sometimes that perfect used chamber comes our way, cheap.
If this is what you have, blow the money on a 12 pack of 2.75 gaskets. once sealed, never open or release those ports not used ever again.

2.75 gaskets are cheap enough to not bother with any attempt at re-using them.

Richard Hull
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Jake Wells
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Re: Used Flange Gaskets

Post by Jake Wells »

But i thought with tons of clamping cf flanges are very good at creating a seal?
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Bob Reite
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Re: Used Flange Gaskets

Post by Bob Reite »

I've gotten away with reusing a copper flange gasket once, by making sure that the mating part goes back on exactly the same way. The gasket itself usually sticks to one part. If the gasket comes off totally, it's nearly impossible to get it back on the same way and it will leak.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
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Re: Used Flange Gaskets

Post by Jerry Biehler »

Jake Wells wrote:But i thought with tons of clamping cf flanges are very good at creating a seal?
Once you take it off there is no guarantee you have a seal anymore. You might if everything lines up just perfect but most likely you will get a leak. Its just not worth messing around with. Order a pack of gaskets from LDS Vacuum and be done with it, at $17 for a pack of 10 you just cant mess around:

http://vacuumshopper.stores.yahoo.net/234copgas.html
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Re: Used Flange Gaskets

Post by Jack Puntawong »

It is as the other have said. One use only. However, if you aren't going into the realm beyond 10^-4 torr, you might want to consider viton gasket. They are more expensive than the copper ones but they are reusable. If you are considering on modifying your fusor again and again, like me, you might want to use them.
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