Re: Toroid Design

> Jim,
> I had not considered that I couldn't bend it.  The 5" stuff was a bit stiff
> and I had to drill holes in the two ends and use lacing cord & tie them
> together as tape alone would not hold it.  I was hoping I could do that also
> with the larger stuff.  The 10" x 50" toroid that I would like to make will
> cost quite a few dollars in aluminum tape alone, it is not cheap.  I like
> looks of the tubing/frame toroid designs but think they would be too
heavy for
> my light weight set-up.
> Ed Sonderman
Didn't someone on the list build a toroid out of screening? How did it

You could cut/buy a bunch of styrofoam circles about 1/2" thick and 10"
in diameter to use as a form. Arrange them in a circle to form the
toroid, use another styrofoam circle in the center. Then, use copper
wire or thin wall aluminum tubing as the actual current carrying
element. If you put the tubes around 1 diameter apart (i.e. 1/4" od
tubes on 1/2" centers) it should work

There is, of course, quite a bit "left as an exercise for the reader"

Also, I've had pretty good luck with 3M Spray 77 adhesive and aluminum
foil as a cheap substitute for aluminum tape. The only problem I have
had is making good contact between layers (the glue is an insulator),
but the same problem exists with the tape.
Jim Lux                               Jet Propulsion Laboratory
ofc: 818/354-2075     114-B16         Mail Stop 161-213
lab: 818/354-2954     161-110         4800 Oak Grove Drive
fax: 818/393-6875                     Pasadena CA 91109