From: Thomas McGahee[SMTP:tom_mcgahee-at-sigmais-dot-com]
Sent: Thursday, August 07, 1997 8:23 AM
To: Tesla List
Subject: Re: Toroids
> From: Jay Bohn[SMTP:sunsoft-at-pacifier-dot-com]
> Sent: Tuesday, August 05, 1997 10:55 PM
> To: tesla-at-pupman-dot-com
> Subject: Toroids
> I have seen quite a few of Tesla Coils topped with a metal toroid.
> Where is everyone finding these?
> Are most home brew?
> What would an alternate "Top Cap. Hat" be? (Copper toilet float)?
> I have been lurking on this list and have enjoyed the info.
> By the way, This is my first "post" ever!
Glad you finally came out of "lurk mode"! Spun aluminum toroids are
very expensive, so most coilers make their own from things like
aluminum dryer ducting. Non-conductive ducting will also work, but
then you have to cover it with aluminum tape or aluminum foil. For
the smaller toroids I scrounge up old vacuum cleaner hose and cover
with aluminum foil. To hold the thing in a round donut shape I insert
either a homemade wooden plug in the ends, or if I can find a pipe
size that will fit, I use a short length of metal pipe to do the job.
IMPROVISE! When you go to your local hardware store, don't look at
what things ARE, but at what you can USE them for!
Metal balls work well as a topload, but then I suggest using a small
toroid just above the top of the coil as a corona shield, as the ball
shape does not shield the top of the coil very well.
Toilet balls are a bit too small in my experience. As a quickie
topload just to get things initially operational I often use a series
of large CANS. Yep, it WILL emit sparks from the edges, but it is a
good quick and dirty way of loading up the top for quick testing. I
often stack several different sizes to get things tuned right.
Sometimes I stack these cans above a small toroid used as a corona
ring so that I don't get strikes to the primary during the testing
As you continue coiling you will probably end up building several
different sized toroids. These can be stacked at times to further
tune your coil.
I always keep my eyes peeled for ANYTHING that is large and roundish
and basically smooth that I can use as a topload. I have used metal
beer kegs, spun aluminum globes, carboard globes covered with strips
of aluminum foil, aluminum foil covered beach balls, spun aluminum
fixtures originally designed for ventilation systems, etc..
Check out the aluminum and plastic cooking stuff... sometimes I find
things like big ladles that I use as spark discharge ground terminals
for electrostatic generators. Two half-sphere plastic bowls can be
epoxied together and covered with foil. Don't look at what things
ARE, but at what you can USE them for. It's amazing what good Tesla
items you can find in almost ANY location!!!
The local dump is a good place to visit on a regular basis!