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Re: Conic Coil (fwd)

---------- Forwarded message ----------
Date: Fri, 27 Jul 2007 23:09:26 -0400
From: Jared Dwarshuis <jdwarshuis@xxxxxxxxx>
To: Pupman <tesla@xxxxxxxxxx>
Subject: Re: Conic Coil

Hi Skip:

we used a long dowel through a graduated stack of glued together Styrofoam
rings. Rotated the dowel with a hand held drill and had a  rigged bushing in
a vise for the other end. A belt sander with 40 grit takes down the stock
while rotating (two man job). Also hand sanded with 60 grit while rotating.
Covered with a thin layer of masking tape (avoid bumps and ridges like the
plague) a coat or two of varnish was applied over the tape to stiffen
it. Needs a really smooth surface to wind over or you get crossover
madness.  So hand sand to 220.

Strike a line on the small end while rotating using an ink pen ( pencil
lines are conductors)

Apply a real thin coat of epoxy and get a few winds started on the line.

DuPont 77 mist adhesive used [sparingly!!!] will save about a million
hours of re wind time.

Takes the tip of your finger to guide the wire ( just loves to jump
and cross.) Be careful that you don't crush the form with excess
cumulative wire tension.

Starting is slow, but once moving you can blast through many pounds of wire
in a few hours (use a geared drill  under 500 rpm  and with a variable

A traffic pylon is about as steep a climb as you can get away with.

Varnish wire to form and whe done realize that the inductor is easily

Styrene is a low loss material.( crystal radio set builders like styrene
for tuner coils)

I have been told that there is no difference between a conic and a solenoid
coil by people who have neither built nor tested them.