Re: Secondary coil form material

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

Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>

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
>