Re: Cap problems (fwd)

To: tesla-at-pupman-dot-com
Subject: Re: Cap problems (fwd)
From: Tesla List <mod1-at-pupman-dot-com>
Date: Tue, 25 Feb 1997 22:24:25 -0700 (MST)
Approved: mod1-at-poodle.pupman-dot-com


---------- Forwarded message ----------
Date: Tue, 25 Feb 1997 00:30:21 -0600
From: Mike Hammer <mhammer-at-misslink-dot-net>
To: Tesla List <mod1-at-pupman-dot-com>
Subject: Re: Cap problems (fwd)

At 09:28 PM 2/24/97 -0700, you wrote:
>
>
>---------- Forwarded message ----------
>Date: Mon, 24 Feb 1997 20:22:50 -1200
>From: Ken Smith <ksmith-at-ihug.co.nz>
>To: Tesla List <mod1-at-pupman-dot-com>
>Subject: Cap problems
>
>Hi,
>        Help please :
>
>I have hit the wall with capacitors.  I have received several designs for
>rolled caps from individuals and gleaned all that I can from the 'net.
>However I am stuffed since I cannot find Al flashing here in NZ at all. They
>just don't use it (as far as I can tell - and I have looked hard - believe me.)
>

You could try a flat stacked plate design using heavy duty aluminum
foil and polyethylene sheeting. I made just such a gap and it is
a great performer. It takes a lot of effort to build one.
Seems to take forever cutting the plates and sheets of poly.


>I have blown several sets of glassware using Leyden Jars (which worked well
>while they lasted, although the spark was very washy and green) and even
>tried beer bottles.  But they didn't last any time at all.
>
>I am running a 15000V 60ma Neon with a twelve pole speed controlled rotary
>+ adjustable static gaps.  I have a lego system now.  My frustration with
>the caps has been vented on the coils (I just love to wind <g>)  I have a
>combination of 6 / 10 / 16 turn 3/8 inch copper primaries and an assortment
>of secondaries all built on idendical formers so they can do a * mix and
>match *.  Results with the *Jars* to date have been noisy and impressive,
>but the glass bill is sending me spare - not to mention the wasted time and
>all that salt water and oil everywhere <g>.
>

One way to stop blowing up your SW caps is to dispose of the
rotary gap. A rotary is not at all necessary with a neon transformer
supply. Neons work well with a multiple static gap like the RQ gap.

A rotary will at times present too wide a gap at maximum voltage
and that causes excess strain on components. The weakest link
will surely self destruct. Right now its your caps.
Now a static gap is just sitting there waiting for the voltage to rise.
Once the voltage is high enough it will arc and clamp the voltage.
The rotary isn't just waiting. Its rotating. And its breakdown
voltages varies from a few KV to a hundred KV or more.
If the point of maximum voltage rise and widest gap on your rotary happen
to coincide, bad things will begin to happen. Blown caps and insulation
breakdown in your neon.
Build a good static gap and save the rotary for a pole transformer.
Mike Hammer
mhammer-at-misslink-dot-net