Liquid HV Feedthrough

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Jerry Biehler
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Re: Liquid HV Feedthrough

Post by Jerry Biehler » Thu Sep 07, 2017 3:53 am

Hysol 1C is good to high vacuum.

ian_krase
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Re: Liquid HV Feedthrough

Post by ian_krase » Thu Sep 07, 2017 7:29 am

Yeah. For best results, get the mix ratio exactly right, mix very thoroughly, and bake lightly after curing.

(also, FYI? Acetic acid will utterly destroy Hysol and turn it into jello.)

However, I am not sure whether Hysol is good enough w/r/t permeation to use as a large vacuum barrier (as opposed to a sealant or an in-vacuum adhesive.

Jerry Biehler
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Re: Liquid HV Feedthrough

Post by Jerry Biehler » Thu Sep 07, 2017 8:53 pm

Hysol 1C is the equivalent of Torr-seal and can be used everywhere.

1C will break down in acetic acid? Im kind of surprised.

ian_krase
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Re: Liquid HV Feedthrough

Post by ian_krase » Fri Sep 08, 2017 1:31 am

Yeah, totally. I accidentally discovered this when I dropped a hysol-based feedthrough in a tub of acidic copper acetate. Later I needed to disassemble a Hysolled component so I broke out the white vinegar and it did the trick.

Niels Geerits
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Re: Liquid HV Feedthrough

Post by Niels Geerits » Fri Sep 08, 2017 6:44 pm

Good to know that simplifies building a feedthrough a lot and makes a liquid feedthrough as a "simple" feedthrough obsolete.

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Dennis P Brown
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Re: Liquid HV Feedthrough

Post by Dennis P Brown » Wed Sep 13, 2017 10:16 am

Here are some poor pictures of the fusor system and my high voltage feed-thru's and one with it operating; the feed-thru system is extremely simple (glass plate, ceramic cylinder, a brass rod and silver & regular epoxy to make.) I will try to get pictures of the new (smaller) design I am currently using. One thing I will say - I use silver epoxy to seal the electrode (metal) inside the ceramic cylinder. After curing, I mount the assembly on the vacuum system (fusor) and using my high voltage power supply run a plasma with the electrode in the high vacuum. The silver epoxy really further cures well and stops out gassing. That stuff makes a very heat tolerant seal (of course, I use forced air cooling to be on the safe side.)

Here are the images of the fusor and older design electrode (no cooling system):

viewtopic.php?f=6&t=10986&p=72749&hilit ... ugh#p72749

Here are the pics of the newer system:

viewtopic.php?f=6&t=11313&p=74615#p74656

Again, when I get some time later this week, I will open my fusor and get more detailed pictures of the electrode feed-thru system.

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