RE: stopping leakage of mineral oil from wire feedthroughs? (fwd)

[<sroys@xxxxxxxxxxxxxxxxx>]

---------- Forwarded message ----------
Date: Wed, 10 Nov 2004 17:23:30 -0800
From: David Trimmell <humanb@xxxxxxxxxxxxxxxxxxx>
To: 'High Voltage list' <hvlist@xxxxxxxxxx>
Subject: RE: stopping leakage of mineral oil from wire feedthroughs? (fwd)

Hi Jack, if you are using a insulated wire from the transformer that is
under oil, and running that wire all the way out to your project, then you
will have many issues with oil. The space between the wires insulation and
the copper will easily transport good quantities of the oil out via
capillary action. The best way to immerse something in oil and run wire out
is to run the connection from the transformer to the lid of its container,
where you have placed a bolt (preferably with a ceramic insulator) through
this penetration. Seal both sides well with an epoxy. Connect to the
out-side... Note that PE does not make good seals with any epoxies or glues
(within affordable range), so (as I am going to ;-)) use a Plexiglas or PVC
lid for your penetrations. 

Good luck,

David Trimmell 

-----Original Message-----
From: High Voltage list [mailto:hvlist@xxxxxxxxxx] 
Sent: Wednesday, November 10, 2004 2:26 PM
To: hvlist
Subject: stopping leakage of mineral oil from wire feedthroughs? (fwd)

Original poster: <sroys@xxxxxxxxxxxxxxxxx>



---------- Forwarded message ----------
Date: Wed, 10 Nov 2004 14:37:08 -0500
From: Jack Vandam <snotoir7674g@xxxxxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>, hvlist <hvlist@xxxxxxxxxxxxxxxxx>
Subject: stopping leakage of mineral oil from wire feedthroughs?

I have been working on a project that requires a small, high frequency
transformer, not too much unlike a flyback, in mineral oil.  I am using a
small plastic container to hold the transformer and have the input/ output
wires passing through the plastic container at several points.  However,
just after completing my first immersion of the transformer, I discovered
that oil was leaking through one of the feedthroughs.  Originally before
adding the oil, I thought I had sufficiently sealed around the feedthrough
holes with plastic weld epoxy.  However, apparently not.  What a mess I had
today draining out the oil and starting over again.  Getting rid of the oil
residue required both mineral spirits and finally acetone.  Now I have to
reapply a sealant around the wires/ feedthroughs.  What is recommended so I
don't have this happen again?  I'm thinking of trying to dispense a generous
amount of silicone around the areas, but would this be better or should I
stick with the epoxy?

Thanks,
Jack