Re: Toroid Smoke

Tesla List wrote:
> >From jim.fosse-at-bdt-dot-comFri Aug 16 13:27:24 1996
> Date: Fri, 16 Aug 1996 05:47:49 GMT
> From: Jim Fosse <jim.fosse-at-bdt-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Toroid Smoke
> Chuck,
> >       Now I'm really havin' fun.
> Isn't it a blast when things start working! Now if I can only figure
> out how to build a cap that will last;)
> >Tonight I had smoke and a very small flame come from the "loose"
> >connection between the secondary and the toroid.  The center disc is a
> >product called Celotex that is 3/4" styrofoam insulation covered on both
> >sides with aluminum foil.  Well, the connection got hot enough to start
> >a small flame, some smoke but little damage.
> I know that electronic components have smoke as the working fluid
> (they must, when you let the smoke out, they stop working;) I didn't
> realize that this extended to Celotex!
> > Spark gap is running a touch rough tonight so I will have to
> >examine it before running again.
> Rebalanced the unit. The electrodes (points) have worn unevenly.
> Pics? and a rehash of you system? It's only been several months and a
> few thousand posts, my memory is going;) 1 to many hits off of a TC?
>         Regards,
>         jim

    Thanks for your comments and interest.  I put together a summary of
what I've been working with so far.  This is my third coil, however the
last one I built was back in 1972, so I better just call this my
first!!  The specs are below along with one photo taken at the end of
June.  I don't want to load down the list server with my other photo's
unless there is interest--so just the one for today.


Tesla Coil #3 Specifications

1. Toroid:	   48" Diameter using 6" diameter aluminum dryer duct as
outer ring, covered with aluminum tape.  The center sheet is a Celotex
Corp. product called "TUFF-R" which is 3/4" thick foam insulation sheet
covered with aluminum foil on both sides.  Toroid is presently
positioned 8" above top turn of secondary.  Absolutely no arcing along
any section/area of the secondary has been seen to date.
2. Secondary:   8" Diameter acrylic form, 1/8" wall, 36" long, with a
28" long winding of #20 wire.  Wire is coated with two coats of Behr
Super Build 50 Polyurethane.
3. Primary:	   1/2" Diameter copper thin wall tube, 1/2" spacing turn to
turn, 11" I.D. and about a 40" O.D. resulting in 15 turns.  Using a
Condenser Products .025mfd. -at- 20KV capacitor.
4. Spark Gap:   Seven gap stationary with fan, in series with a rotary.
Rotary has 12 points (3/8" stainless stell acorn nuts) on a 14" diameter
G-10 glass epoxy disc using a Carter 1 H.P. 0-10,000 RPM motor.  (Used
at a 2200 RPM setting right now). 10 amp variac runs the Carter motor.
5. Power Supply:    10 KVA 14,400 VAC Pole Pig with a Century welder for
current limiting in parallel with oven elements (Oven elements are a new
addition).  0-280 VAC at 28 amp Powerstat 1256 series variac for power
control.  Simpson 0-300 VAC and 0-50 Amps AC Analog panel meters to see
how close I am to popping the breaker!
6. One Big "Emergency Off" button!!  That's all I can remember for now.