Re: Toroid Design

In a message dated 12/19/98 6:35:39 PM Pacific Standard Time, tesla-at-pupman-dot-com

 Ed,           -snip-
 You definately need a larger ROC toroid - 8" or 10" (perhaps even 12")
 should work. Be forewarned, however, that the increased breakout voltage
 will place significantly more voltage stress on your 6" coil, and you
 may begin to get interturn flashovers. I presently use an 8" ROC on a
 system that delivers only 65" streamers, and get excellent field control
 and single-root streamers. I also went through a 4", two 6", before
 settling on the 8" ROC toroid in the processs! 
 For ease of construction and low cost, flexible aluminum ducting can't
 be beat. Aluminum ducting is available in these diameters, but you may
 need to go to a heating/ventilation supplier. I got my 8" material at a
 Home Depot, but it was the largest they stocked.
 Safe coilin' to you, Ed!
 -- Bert --

Maybe I will try an 8" x 50" toroid made out of aluminum ducting material.  I
am familiar with the smaller diameter variety that I used to vent my dryer.
It comes in what looks like short lengths all scrunched together and you just
pull it out to the desired length to use it.  Is this the same material?  Any
tips on how to make toroids out of it?  It seems like it wourd be quite
fragile - if dropped or banged into something, it will dent correct?  Can you
repair the dents?  If I can get 8" diameter material, I would cut out a 32"
diameter circle of .25" thick acrylic and wrap the ducting around it then
cover the center with aluminum tape.

I sure don't want to overstress my 6" coil and destroy it.  How do you know
when to stop this madness?

Ed Sonderman