Re: New coil

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

Original poster: Brett Miller <brmtesla2-at-yahoo-dot-com> 

John,

Tesla list <tesla-at-pupman-dot-com> wrote:

Original poster: "John Richardson"

Hello,

Well, last night I fired up my new 4.5" coil, and
performance was great for a first fire, but I do have a few questions and
comments for the list. Here's the specs:

Secondary: 4.5" OD PVC with 36" of heavy build #24. Set 1" above primary,
last winding 3" from top of form. Total pvc length 42".

Primary: 14 1/4 turns of .25 Cu tubing.

Toroid: Quick lash up of 4" dryer duct. 24" by 4".

Gap and cap bank: 8 942 CD's in series mounted next to a five segment
copper pipe gap blown with a small muffin fan. Everything mounted on two
sandwiched 8 by 11 cutting boards.

Transformer: Transco 12/60.

Upon first fire up, I tapped at turn 14 1/4, as I usually start from the
outside in when first firing. This happens to be the number of turns I
wound up with before running out of a full roll of tubing. Instant multiple
streamers, maybe four or five at a t! ime, with the longest consistently
hitting the 36" mark.

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Sounds like you're doing fine for a first light situation.  You have some 
real fun stuff going on there.

 >A few comments on the physical design of this unit. The whole primary base,
 >including the primary supports, are made out of plywood, so to those who
 >feel that HDPE or similar is required, don't be afraid to work with wood if
 >that's all you have.

I think for a lot of climates and elevations your above statement is a 
scientifically sound one.  But there may be some fatal exceptions.  As 
Terry, myself and others found out in the GMHEICSLR contest, elevation 
above sea level (atmoshperic pressure) and the associated humitity have a 
great deal to do with spark length limitations.  Humitity in particular has 
an enourmous effect on the dialectric (or conductive under high voltage) 
properties of wood.  I don't know what you're location is, but I live near 
Chattanooga, TN where it is *extremely* humid year round.  I have found 
wood to be horribly lossy in nearly every tesla application (except as a 
conductive platform for arcing to metal objects.  On my hot-streamer 
website you can see my 6" system blasting out extremely hot power arcs to 
an aluminum chair which is resting atop a wooden chair.  The aluminum chair 
is not grounded (except through the wooden chair to the rebar! in our 
concrete floor.  I could actually see four little continuous arcs from each 
leg of the wooden chair into the floor while the coil was power arcing to 
the metallic top chair.

Another anecdote is a linear 1/2" multi copper pipe gap Terry sent me so I 
could compare with a scope trace showing the quench performance of my own 
gaps.  The base of his gap was wooden.  The gap had provided first notch 
quenching in his systems, but performed very poorly (lossy) in mine. 3rd or 
4th notch quenching.  But the worst thing (and finally getting to my point) 
was that some of the time it would not fire, but just lock up and 
sizzle.  It turned out that half the time the whole thing would undergo 
corona breakdown due to the moisture it had absorbed into the unfinished 
wood surface in our continuous 80% plus humidity.

Oh well....just some anecdotes and food for thought.

-Brett         hot-streamer-dot-com/brett



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