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Formless Coil upate

Well, so far I have tried Varnish, Polyeurethane, Polyacrylic (H2O based
Polyeurathane), and this weekend, Epoxy and Behr build 50.And by the way I am
now coating the paper tubes with Saran Wrap now instead of Mylar, with much
better results. Smoother insides, clearer, and peels away better. I am sorry
to report that the varnish based one was the least rigid and least appealing
of all samples so far.The epoxy seemed strongest, even though only 1 coat, it
was by far thicker than even 7 coats of Polyeurathane. The Behr build 50 also
only needed only 1 coat and is absolutely the most beautiful of them all!! I
had a heck of a time finding it but finally found it at a new Home Depot for
$35 for 3 qts (2 resen 1 hardner) it was intended for covering things like
chess tables. Advertised that it covers on 1 coat the same as 50 coats of
other coatings. Hats off to the person that first mentioned that to the
group! (my memory for names is horrible) The Berh 50 does seem to be a bit
more on the brittle side. Maybe scaled up, if a coil were to drop, it might
shatter. In this stiuation, the Polyeurathane is the most forgiving, yet
still strong, not as pretty at all. The Epoxy based one I think would hold up
and also be able to mold into a stand or incorporate a termal or attachment
point. My epoxy version had air bubbles in it form, I am hoping it was from
to fast a cure, I used 30 min Epoxy. I will retry this next weekend with 24hr
Epoxy. I picked up some interesting stuff at AIN Plastics in Detroit this
weekend. One was an Acrylic casting compound called Castolite AP($20 qt). It
is used for imbedding things in a Acrylic cube. The other wasCastolite AC($21
qt) same type of stuff, but much longer cure time (and heat), but is
optically clear. It was meant for casting biological samples. I can't wait to
try them out! I must do something better with my ventilation for that stuff,
though!(WOW, powerful stuff!)

After I finish with the last coil, so far all of them are the same # of turns
and same dia., I will test them at work to see their physical differences on
paper. I will then post the results.

I now am confident that I will now never again have to shell out big bucks
for a coil form any more! This was actually an unthought of byproduct. I
orginally set out to get a better Q secondary, which I will in the end I will
have. Like an airplane or spaceship design, every bit of weight(or in our
case energy) savings is a good thing! By the way, 10% on a balanced primary
is a big thing in my book!

Now that I will have all these identical samples, I have a few ideas of my
own for electrically testing them.

I am asking the group if anyone has a particular test that they would like me
to perform on them to evaluate the effects of the different coatings.

I think that is about all of the typical coil coatings that I can think of.
If anybody has another coating that they would like for me to include, please
let me know.

By the way, now that I think of it, I might want to mechanically test them
after the electrical tests!! Please send electrical test suggestions soon, I
don't drag my feet too long.

                          Kevin M. Conkey