Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Electrical DIY Electrical Feedthrough

  1. Jul 20, 2015 #1
    I want to build high voltage feedthroughs (vacuum) from epoxying pieces of alumina together, and then epoxying alumina strips on the outside to cover the spaces between. Can I use JB weld, as far as things go electrically? People have reported that JB weld is unexpectedly wonderful for vacuum.

    Provided I have the correct amount of alumina per the amount of kv im applying to it, the electricity wont break down or break through the linings of epoxy will it? It's very expensive to get blocks of alumina and machine them
  2. jcsd
  3. Jul 21, 2015 #2
    I think it would be useful to see a drawing of the feedthrough and where you intend to use the epoxy. Also what vacuum are you trying to maintain?
  4. Jul 21, 2015 #3
    A vacuum of 10-4 torr, it's really not a question of design it's more about the epoxy, im asking if the voltage will be able to move through the epoxy and connect to the vacuum chamber or other nearby objects within the voltages reach.
  5. Jul 21, 2015 #4


    User Avatar
    Science Advisor
    Gold Member

  6. Jul 21, 2015 #5
    Unless you have the specs on it dielectric strength, or test it with at least twice voltage you intend to use I wouldn't use it. Why do you have to make your own feed through? Experimental rule: if you can buy a part that meets your needs at a reasonable price then buy it. High voltage vacuum feed throughs are common accessories for vacuum systems.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook