coil form losses

To: tesla-at-pupman-dot-com
Subject: coil form losses
From: kcRavens <kcravens-at-sound-dot-net>
Date: Sun, 1 Sep 1996 07:40:20 -0500 (CDT)
At 10:25 PM 8/31/96 -0600, you wrote:
>>From SSNSanders-at-aol-dot-comSat Aug 31 21:56:34 1996
>Date: Sat, 31 Aug 1996 12:27:12 -0400
>From: SSNSanders-at-aol-dot-com
>To: Tesla-at-pupman-dot-com
>Subject: Coil Form Losses
>
>When losses are due to the thickness of a form does the form actually absorb
>the power , like wicking up the RF and causing less output and shorter arcs?
>So the thinner the form the less absorbtion, or a different material such as
>plexiglass has less afinity for penetration of RF?  I wound a beautiful coil
>on sch 40 pvc. 28 inches of # 22 and probably have 20 coats of varithane on
>it but somehow, by being in a hurry ,HEH HEH, I didnt prep it and now im
>afraid its just not going to work. Should I just trash it and start over?
>Also does anyone know of available plans for a rotary gap construction? AND,
>what are you fellows using, You speak of tungsten for gap electrodes, is it
>nuts, cap nuts, a reshaped ease out or what?   Thanks , Steve.


Steve,
        Just an amateur here, but I'd go ahead and use it! I've got a 5 inch
dia, 36 inch, #22 formvar coil.  My grandfather wound it over 35 years ago,
and its on a cardboard tube. It was stored for years, and got soggy on one
end from water damage (at some time or other) but I sprayed a couple of cans
of clear acrylic on it, and plugged the ends with wood. The cardboard looks
to be about 1/16" thick, but had a ton of varnish or shellac on it,
apparently just the outside tho.
        With one 9k 60ma neon tranny, .05 home made poly caps, and 8 to 10
gaps (static) it puts out 3' of purplish white lightning. Not too bad
considerin' the jerry-rigged setup I got (pictures WON'T be posted) :o) But
with the same exact components substituting a 6" by 28" plexiglass tube 1/8"
thick, I get about the same 3' sparks to air, but have to adjust the primary
tap a turn or two. So anyways, I wouldn't "trash" your unprepped sch 40 pvc
coil...at least save it to compare with your soon to be wound "best coil
yet" :o)

                                         Happy coilin'
                                                
                                                       Ken