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Re: [TCML] I think I ruined my 6" secondary.



Interesting how every says that the secondary is likely to shock you.  I use
the same sort of epoxy and I have never been shocked by the secondary.
Maybe that's because it's so humid here the thing just won't hold a charge
for more than a few seconds.

On Sat, Jul 5, 2008 at 12:42 AM, Quarkster <quarkster@xxxxxxx> wrote:

> David -
>
>  I think there may be some misunderstandings in this thread.
>
>  If Scot's Behr 50 coated coil showed "seperation" between the windings and
> the Behr 50 epoxy coating after being subjected to an "impact", what
> occurred was a bond failure between the secondary winding and the coating,
> and probably had nothing to do with the epoxy "becoming brittle". If the
> epoxy coating was brittle, it would have cracked, chipped or shattered
> (spider-webbed) at the point of impact. This type of bond failure can occur
> if the secondary windings were not carefully cleaned with a solvent (like
> isopropyl alcohol) immediately prior to applying the epoxy coating. After
> winding, a secondary is likely to be covered in oily fingerprints
> (invisible, but definitely will prevent good long-term coating adhesion).
>
>  The 2-part epoxy coating actually named "pour-on" is "EnviroTex Lite
> pour-on HIGH GLOSS FINISH" (as written on the package). This is sold by
> Environmental Technology, Inc in Field's Landing, CA. (See:
> http://www.eti-usa.com/consum/envtex/envlite.htm). In Southern California,
> I have purchased this material at Ace Hardware stores.
>
>  I've used this material over the last ten years to coat over a dozen
> secondaries (#22 AWG through #34 AWG) and it has performed spectacularly.
> One coat provides a very thick (at least .050"), slightly flexible,
> glass-clear coating. I've never had any problems with delamination,
> cracking, crazing, discoloration, or secondary damage from "racing arcs" or
> self-strikes. When done correctly, this coating yields a thick, transparent,
> mirror finish that looks like the windings are encased in a heavy glass
> sleeve. I've dropped secondaries, accidentally knocked them against all
> sorts of other objects, scraped them against sharp edges, etc, etc and never
> sustained any significant damage.
>
>  The EnviroTex resin has a viscosity similar to heavy syrup, and a
> motorized fixture is required to keep the secondary slowly rotating for
> several hours while the epoxy cures. Pot life is at least 1/2 hour at 70
> degrees F, and gel time is about 2-3 hours with full cure in about 12 hours.
>
>  At one point I also tried the Behr-50 epoxy, but I didn't obtain as good a
> finish as I got with the EnviroTex material.
>
>  As Scot noted, epoxys are very good insulators and make good electrets.
> After running a Tesla coil with an epoxy-coated secondary, disassembling the
> system always provides some fun when removing the secondary. I've taken some
> good discharges to the forehead and the navel when lifting a 6" X 32"
> secondary out of the primary supports. Depending on the ambient humidity,
> this secondary is usually good for at least 2-3 good jolts.
>
>  Herr Zapp
>
> David Rieben <drieben@xxxxxxxxxxx> wrote:
>
> Hi Scot,
>
> So you're saying that the Behr's 50 will eventually
> deteriorate over time? I think that's the first negative
> trait that I've heard mentioned about this stuff. Well,
> like I said, it takes a bunch thin coats of the Minwax
> Marine Spar Varnish to build up a shell of decent
> thickness but I agree with Bart Anderson that this is
> one of the best commonly availabe products for the
> secondary coil coating. My Spar Varnish coatings
> have always lasted for years w/out significant dete-
> rioration in my unclimate controlled shop. I had
> thought that the Behr 50 epoxy would be great but
> your comments about its lack of long term durability
> have got me questioning its suitability now....
>
> David Rieben
>
>
>
>
> ----- Original Message -----
> From: "bunnykiller"
> To: "Tesla Coil Mailing List"
> Sent: Thursday, July 03, 2008 7:05 AM
> Subject: Re: [TCML] I think I ruined my 6" secondary.
>
>
> > Hey David..
> >
> > The pour on stuff I used was Behr 50, a 2 component material. It was
> > very nice to use, thick like an epoxy ( I believe it was an epoxy) once
> > dried it was somewhat resiliant, but after a few years it becomes very
> > brittle and when you bump the coil, the wires seperate from the coating,
> > leaving large "air gaps" between the wire and coating. I do have to
> > admit tho, the exterior finish has held up to years of abuse with
> > minimal scuffing ( still shiney) and one more thing, the Behr 50 is
> > quite prone to the effects of holding a charge on the coil ( very strong
> > zapping capacity :) on my 12"X5' secondary it was like being hit by a
> > Taser, couldnt move my leg properly for a couple of minutes after the
> > main shock).
> >
> > Scot D
> >
> >
> > David Rieben wrote:
> >
> >> Hi Phil,
> >>
> >> Can you tell us what the name of this stuff is? I have heard
> >> of Berh's "pour-on" but have never been able to find a pro-
> >> duct by that particular name in my local building supply stores.
> >> (Plenty of Berh's paint products, but no Pour-On).
> >> I have been using the Minwax Marine Spar Varnish on my
> >> coils for the last several years now with good success but
> >> of course it has to be applied via multiple thin coats to get
> >> a reasonably thick coating.
> >
> > snipperz
> >
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