Re: All pain no gain

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Bert Hickman by way of Terry Fritz <twftesla-at-uswest-dot-net>" <bert.hickman-at-aquila-dot-net>

Nathan,

Have you tried putting a piece of wire or a nail on your toroid to force
breakout and then tuning for best spark? I ran through some of the
numbers you provided using my personal spreadsheet and I'd estimate that
you should be in tune in the range of about 17-19 turns. Since I don't
have your primary's inner diameter or turn-turn spacing it's difficult
to be more precise.

Your tank cap is a bit on the large size for the NST you're using, but
if your gap is firing you should still be able to tune for best spark
length. Are your capacitors heating up significantly when you run the
coil? Do you have the manufacturer and part number for these caps? If
you still can't get the system to break out after setting up your system
for best tune, you may need to increase the voltage and current of your
NST - a 9000 volt 30 MA NST would work a bit better. Another alternative
is to decrease the minor diameter of your toroid by using 3" dryer duct
rather than 4". 

Try tuning the system and let us know the results...

Best regards and safe coilin' to you!

-- Bert --
-- 
Bert Hickman
Stoneridge Engineering
Email:    bert.hickman-at-aquila-dot-net
Web Site: http://www.teslamania-dot-com

Tesla list wrote:
> 
> Original poster: "Nathan Morris by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <themfam-at-home-dot-com>
> 
> All,
> Thanks for all of the suggestions.  Here are the specs on my coil and more
> information on my attempted first light setup.
> 
> I used the JavaScript Tesla Coil Designer
> For Classic Dual-Tuned Resonant Transformers
> JavaTC 7.04
> Copyright © 2000 by Barton B. Anderson
> 
> My primary is 23 turns of insulated #10 AWG stranded.
> My secondary is #30 mag wire on a 19 x 4.5 PVC form.
> My torroid has an ID of 8 inches an OD of 16 inches and a chord of 4 inches.
> For the first light attempt I was running small a 7.5 kv 20 ma NST (no
> variac)
> My cap is two rows of four .02 uf 3kv caps.  The two rows of four are
> parralled for a total tank capacitance of .01 uf.
> My gap has 4 gaps that are quenched by a 120 VAC microwave blower.  Each gap
> is individually adjustable.  Before energizing my primary I set the gap so
> that all 4 were sharing the duty.
> JavaScript Tesla Coil Designer suggests a primary tap at turn 25.  I got
> shorted on my wire from the hardware store so I was using the length of my
> primary.  I thought it might be close enough to get me started but to be
> quite honest I believe it is the main issue with my current setup.
> Oh yea, almost forgot, I was using the wall outlet for grounding my
> secondary.  While mowing the yard however, I did find 2 inches of a copper
> ground rod sticking up near my service entrance/breaker pannel.
> 
> ----- Original Message -----
> From: Tesla list <tesla-at-pupman-dot-com>
> To: <tesla-at-pupman-dot-com>
> Sent: Wednesday, March 07, 2001 8:27 AM
> Subject: Re: All pain no gain
> 
<SNIP>