Re: New 4" coil: R.Hull and CSN, Secondary Varnish

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "S Gaeta by way of Terry Fritz <twftesla-at-qwest-dot-net>" <sgtporky-at-prodigy-dot-net>

Yes, I have used it, and it protects against mechanical abuse better than
polyurethane. However I suspect it is not very good high voltage insulator.
I have used it on my replacement secondary for the medium coil. the new
secondary is exactly the same as the old in every way, except for the
coating. The old one was coated with polyurethane. Preformance wise there is
no difference between the old, and new secondary.

I also used it on my 811A coil, and this is where things get interesting. I
used a thin form to wind the secondary. It was 1/16th inch hard plastic,
probably HDPE, used as a spool for blueprint paper. Even after I coated it
with the epoxy, I decided that it was still too flimsy, so I enclosed it in
a larger diameter PVC pipe, and sealed the ends with clear lexan.
After I run the tube coil for longer than 5 minutes, I notice that
condensation forms on the inside of the lexan. This suggests to me that the
epoxy may be hygroscopic, and when the secondary gets warm, the water
evaporates out. Again no failures have occured as a result, but I just
thought that this should be mentioned.

Also, you have to really mix, and beat this stuff to death for at least two
minutes after combining the two parts, otherwise it will not cure properly.
It is also worth mentioning that if you apply it over fully dry Minwax
polyurethane, it will not screw it up.

Sue

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, September 20, 2002 12:57 PM
Subject: Re: New 4" coil: R.Hull and CSN, Secondary Varnish


> Original poster: "Writeme Now by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<writeme42-at-hotmail-dot-com>
>
> Hi,
>
> Has anyone ever used enviro-tex as a secondary coating.
> Its the stuff they use on bar tops for a rock hard finish.
>
> Cheers,
>
>         Dan
>
snip