[AMRadio] Oil filled capacitors

rbethman rbethman at comcast.net
Mon May 19 17:56:12 EDT 2008

I would NOT use JB Weld under ANY circumstance for THIS application.

I do have issue with silicone being an issue!

Silicone tape, Type 70, by 3M, is used in high voltage terminations AND 
splices when they are taped type in lieu of the (junk) resin type.

I've run silicone tape up to 13,800VAC.


click on documentation.  READ the PDFs

This is an indicator of silicone [NOT silicon!] use with HV.

I would NOT trust 5 minute epoxy.

First problem with 5 min epoxy is it's lack of strength.  IF epoxy IS to 
be used, make it either 30 min or 60 min epoxy.

Bob - N0DGN

Gary wrote:
> Rick:
>     I would use the 5 minute epoxy. I have seen silicon also track a short 
> to ground but not like JB Weld. I have tested the 5 minute epoxy at 5KV and 
> it held steady, no problem. Passed a PI test with flying colors.
> Regards,
> Gary...WZ1M
> ----- Original Message ----- 
> From: "Rick Brashear" <rickb at tx.rr.com>
> To: "'Discussion of AM Radio in the Amateur Service'" 
> <amradio at mailman.qth.net>
> Sent: Monday, May 19, 2008 4:32 PM
> Subject: RE: [AMRadio] Oil filled capacitors
> Thanks, Gary.  There is nothing better than an actual test to make sure of
> the properties of a substance.  Since it showed a short at 500 volts I don't
> think it would like the 2500 volts that will be applied to the capacitor.
> Maybe I better go with the silicon just to be safe.
> 73,
> Rick/K5IAR
> Well, I could not resist. I have a tube of JB Weld in the shop and for
> giggles put some on a piece of Nomex paper. I then dug out the hipot tester
> and started to apply a dc voltage to each side of the glob of JB Weld. At
> 300 volts it started to show a high resistance leakage and at 500 volts went
> to a solid short. I would not use it for the application intended on this
> thread.
> Regards,
> Gary...WZ1M

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