RE: Form Material Info!!!

["Malcolm Watts" <M.J.Watts-at-massey.ac.nz> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi Dan,

On 15 Jul 00, at 10:41, Tesla list wrote:

> Original poster: "Dan Kunkel" <dankunkel-at-hotmail-dot-com> 
> 
> Gary,
> 
> why then do so many coilers "prep" their pvc forms by drying them with an 
> oven and coating them with poly? is this considered an outdated procedure? 
> are you saying all secondary form materials are the same in terms of 
> performance?

They aren't - but most that you can think of are fine. Let me 
recount a personal experience with the good and the ugly.
     My best secondary (to date but that will soon change) is 
wound on unsealed thickwall PVC drainpipe. I can detect a 6% 
difference in its unloaded Q between damp and dry days. 
     At the other end of the scale I once built a secondary on 
a piece of sonotube with the tar paper removed. Nothing wrong 
with the wiregauge and it had a smaller aspect ratio as well 
as being spacewound. Unfortunately it was not sealed to an 
acceptable standard and its Q came in well under 100. I 
concluded that significant conductivity was not a good idea.

Regards,
Malcolm