Re: New coil

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

Original poster: Edward Wingate <ewing7-at-rochester.rr-dot-com> 

Tesla list wrote:
 >
 > Original poster: "John Richardson" <jprich-at-up-dot-net>

<Snip>
 > I live in upper Upper Michigan,  and humidity really isn't a problem.  Right
 > now it's 19 below on the thermometer, and I've got the frostbite on my
 > fingers to prove it.  Why can't the water pump freeze during the day instead
 > of 11 pm?  They don't show people welding cracked pump cases and thawing
 > pipes with a torch at 2 in the morning in any of these country living
 > magazines, do they?  Or how about 6 inches of raw sewage in the basement
 > 'cause the septic is frozen?  Just glossy pictures of pretty, snowy
 > landscapes with horses running around, etc.  What a crock.
 >
 > Anyhow, and to the point.  I can see what you're saying with regards to wood
 > absorbing water, especially in a locale such as yours.  To be honest, I was
 > planning on using HDPE, but didn't have the patience to wait for an order
 > from McMaster or the willingness to drive 60 miles to the nearest Wal-Mart
 > for cutting boards.  As usual, I was in a hurry.  Even before coating with
 > poly, though, I couldn't see any tell tale corona on the wood supports, and
 > I actually expected to.  It's amazing that high voltage can find a path
 > anywhere, as anyone who has run their leads on a cement floor can attest to.
 > That pesky blue haze follows those wires anywhere they touch or come close
 > to cement, table top corners, etc.  Anyone else out there have problems
 > using wood?  If memory serves, I thought Ed W. has a conventional coil with
 > a ribbon primary run through plywood slots.  And he's running meter spinning
 > power levels in everything in that garage of his.  Then again, he's in snow
 > country as well.  I'll keep you posted if things change, as I'm gonna hit
 > her with 3kw just to see if the wood can hold.
 >
 > Thanks,
 > John Richardson

Hi John,

Your first paragraph had me laughing so hard I almost fell out of my
chair, because as you say, I live in snow country too. Ever consider a
career in stand up comedy?  The temps here aren't quite as low as yours
but we come close sometimes.

You are correct, my 18" conventional coil does have SOME slotted plywood
primary supports. I say some because three of them have been replaced
with Lexan over a period of time due to the fact that they literally
blew up when carbon tracks formed inside the layers of the plywood. I
used a poplar plywood from one of the local building supply stores and
suspect that the glue they used in that particular plywood is
conductive. Moisture didn't appear to have anything to do with the
failures as I've never had a problem with regular spruce or pine plywood
or solid wood in past projects, but would recommend using Lexan or some
kind of plastic in preference to wood for longevity and reliability.

Ed Wingate RATCB