Re: Secondary coil form material

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

Original poster: dhmccauley-at-spacecatlighting-dot-com 


When looking at PVC, the grey PVC (Type I PVC) electrical type conduit has a
much better dielectric breakdown than standard
white PVC commonly used in drainage, sewage, water, pipes etc...

I always thought the grey PVC had more carbon in it and therefore more
conductive, but actually the opposite is true.

PVC is just fine for tesla secondaries.  Even cardboard sonotubes which many
claim are very poor coilforms.  I've gotten almost 8 foot arcs using a
10" cardboard sonotube with only about 3.5kW of input power.  Thats pretty
good I think.

Dan


 > Hi Luke,
 >
 > At 01:20 PM 1/16/2004, you wrote:
 > >What are some of the better commonly used coil for materials.
 > >PVC is what I would like to use simply for availability.
 > >But from what I have read PVC has a high dissipation factor.
 >
 > Not a problem.  Any plastic is fine.  But do avoid black plastics that may
 > contain carbon.  Some drain pipe has a soft black layer on it that is
 > filled with carbon and can short out the whole coil.  Stick with the
white,
 > green, or other non black plastics.  Any of the clear plastics are fine
too
 > but cost a bunch more.
 >
 > >
 > >Has any one designed a system with PVC and the changed no other aspects
of
 > >it but to wind an identical secondary on say Polyethylene or some other
 > >material?
 >
 > "i" have not.  But we can measure the "Q" of a coil and plastics are very
 > low loss.  Below what we would care about.
 >
 > >
 > >If so what were the results?
 > >
 > >How much would my arc out put suffer if I used PVC?
 >
 > Not at all.  The cardboard "sonotubes" used for concrete forms do have
much
 > higher loss and can decrease spark length about 5%.  People like it
because
 > it is so easy and cheap to get though.  But it is vastly more lossy than
 > any plastic.
 >
 > If you are going to coat the tube with say paint or something.  I would
 > test it first to be sure the coating will not eat up the plastic.
 >
 > Cheers,
 >
 >          Terry
 >
 > >
 > >Luke Galyan
 > >Bluu-at-cox-dot-net
 > >
 >
 >
 >
 >
 >