Good Diffusion pump?

Every fusor and fusion system seems to need a vacuum. This area is for detailed discussion of vacuum systems, materials, gauging, etc. related to fusor or fusion research.
Noah_Finlinson
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Good Diffusion pump?

Post by Noah_Finlinson » Fri Mar 09, 2018 7:29 pm


Rex Allers
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Re: Good Diffusion pump?

Post by Rex Allers » Fri Mar 09, 2018 10:09 pm

Sorry about being a net-cop, but the heading of the group you are posting in says this,
"Do not post simple questions here. Use the New User Chat area"

Your post is very basic, that comes up with many new members, and also contains ephemeral links that don't need to be preserved long-term as they will be in the Vacuum Technology section.
Rex Allers

Jerry Biehler
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Re: Good Diffusion pump?

Post by Jerry Biehler » Sat Mar 10, 2018 3:59 am

First one is a 6" pump, way too big. Second should be about right. Looks to be a custom flange and you will have to make your own adapter.

Noah_Finlinson
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Re: Good Diffusion pump?

Post by Noah_Finlinson » Sat Mar 10, 2018 4:58 am

Rex Allers wrote:
Fri Mar 09, 2018 10:09 pm
Sorry about being a net-cop, but the heading of the group you are posting in says this,
"Do not post simple questions here. Use the New User Chat area"

Your post is very basic, that comes up with many new members, and also contains ephemeral links that don't need to be preserved long-term as they will be in the Vacuum Technology section.
No, thank you for informing me. I am still quite new to this and I was not very observant. Thanks and have a good day!

ian_krase
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Re: Good Diffusion pump?

Post by ian_krase » Sat Mar 10, 2018 8:53 am

Neither of those are conflat flanges. They don't have the chunky dimensions and knife-edge. Like most diffpumps, they have plain pipe flanges, in some cases with o-ring grooves. These may be standardized or may be oddball flanges you will need to make an adapter for.

prestonbarrows
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Re: Good Diffusion pump?

Post by prestonbarrows » Sat Mar 17, 2018 2:52 am

Definitely not conflat flanges. Conflats have 'knife edges' with ~30 degree 'triangles' to create metal-to-metal seals. What you have shown are square profile o-ring grooves. Totally acceptable, but you will need to measure the grooves and purchase the proper o-ring to fit inside it. Diff pumps typically are o-ring sealed, no worry there.

Diff pumps are also notoriously bomb-proof. Unless there are literal bullet holes visible in the sides, you can usually safely assume they will perform well once properly cleaned, filled with the proper oil, and run at the proper conditions.

ian_krase
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Re: Good Diffusion pump?

Post by ian_krase » Sat Mar 17, 2018 6:50 pm

Ehhhh, sometimes ignoramus surplus ironmongers will lose the Christmas Tree from the center and not tell anyone.

John Futter
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Re: Good Diffusion pump?

Post by John Futter » Sun Mar 18, 2018 1:06 am

Noah

We frown on people who repeat what others have written it wastes server space
You should not have copied Rex's reply into your reply ----totally redundant

this is not Farcebook or Twotter it is a repository of good information that does not need dilution

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Richard Hull
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Re: Good Diffusion pump?

Post by Richard Hull » Mon Mar 19, 2018 5:54 am

Thanks John. Your reminder about not copying what is in the immediate prior post is one of my pet peeves. I have posted on it often. I often wonder what drives people to do that.......

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

Adam Binns
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Re: Good Diffusion pump?

Post by Adam Binns » Tue Mar 20, 2018 1:20 am

https://www.ebay.com/itm/Varian-Air-coo ... SwjlBaMdwi if you live in the US this is a great deal as it has a throttling valve as well as being air cooled.
I'm not going to bother buying it as down under the outlet voltage is different as well as the shipping being 90 dollars.
I believe Richard hull recommends an air-cooled pump because they don't need a constant supply of water to run.
"it's not illegal just don't get caught"

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