Re: Capacitors

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

Original poster: "Tim by way of Terry Fritz <twftesla-at-uswest-dot-net>" <warpath-at-wtp-dot-net>

Hi Mike, Herein lies the question-what size cap do I need? I have tons of
information on computing
cap size but for the life of me, I can't make sense of it. Any and all help
is truly appreciated.My
transformer is a 15000volt nst with output of 450VA at 30MA. So far this is
all I know except that I
won't make a plate stack cap. Later, Tim

Tesla list wrote:

> Original poster: "Mike Waddick by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <mikew-at-winternet-dot-com>
>
> terry, tim,
>
> I agree with Terry totaly. I have made a homebuilt cap and it was big. I had
> it in a big plastic container and was filled with gallons of oil. I once
> spilled the oil out and man was it messy. It weighed about 150 pounds
> (atleast) i trashed the thing before every using it.
>
> I then bought some caps from Mike Novak who did a bulk buy. I used these
> caps in a MMC that costed me about 80 dollers in teh end.
>
> i used to buy my caps from Hosfelt electronics. there GE caps that were 3kv
> at .1mfd. These were nice little caps. And very cheap. Once i informed Mike
> Novak he canceled his order for the caps from teh bulk buy and went out and
> bought over 200 dollers worth of these caps. So with all the buying of these
> caps i bought out the last ones that had.
>
> do you know what size cap you will need? i made some strings that are
> mounted on acrylic strips and are rated at .01 at 30kv and have drilled
> brass hook ups.
> i would be willing to sell you one of these strings for 20 dollers, they
> should last awhile
>
> mike
> ----- Original Message -----
> From: "Tesla list" <tesla-at-pupman-dot-com>
> To: <tesla-at-pupman-dot-com>
> Sent: Thursday, December 21, 2000 9:34 PM
> Subject: Re: Capacitors
>
> > Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>
> >
> > Hi Tim,
> >
> > Welcome to the wonderful world of coiling!!
> >
> > Your transformer is perfect but be sure to use safety gaps across it so it
> > does not burn out.  Tesla coils and caps can interact to create high
> > voltages that can destroy an unprotected transformer.  A fancy filter is
> > nice like the ones below but a simple safety gap is the minimum.
> >
> > http://hot-streamer-dot-com/TeslaCoils/Misc/NSTFilt.jpg
> > http://hot-streamer-dot-com/TeslaCoils/MyCoils/BigCoil/protection.jpg
> > http://hot-streamer-dot-com/TeslaCoils/MyCoils/SmallCoil/small_protection.jpg
> >
> > I "think" your LDPE sheets need to be like 60 to 90 mils for a 15kV NST!?!
> > I am not an expert on this but others will chime in here.  I do want to
> > point out that another brand new kind of primary cap called the MMC is a
> > far better choice IMHO.  They have obsoleted the oil filled poly caps very
> > quickly.  Information on this is at:
> >
> > http://hot-streamer-dot-com/TeslaCoils/MMCInfo/mmcinfo.htm
> >
> > Feel free to ask more questions because I am sure your have a bunch :-))
> >
> > Cheers,
> >
> > Terry
> >
> >
> >
> > At 08:04 PM 12/21/2000 -0700, you wrote:
> > >Hi to All, My name is Tim Walrath. I am endeavoring to build my first
> > >Tesla Coil. I have purchased a 15000 volt neon sign transformer that
> > >puts out 450VA at 30MA. I am wanting to build my own capacitors. I am
> > >planning on using LDPE sheets at 6mil thickness and aluminun roof
> > >flashing for the conductor plates. I am purchasing some polypropylene to
> > >make the cases and plexiglass to make the tops. I am having trouble
> > >figuring out how to figure the capacitance needed for the caps- that is
> > >how much LDPE to use between each conductor plate. Math never was my
> > >best subject but I do want to be able to figure this out. Any help would
> > >be appreciated. Thanks, Tim
> > >
> >
> >