* Carbons Sent to: rob-at-atitech.ca

Quoting Rob Bicevskis:
Subject: Litz  Wire

 RB> I am accumulating 'junk' for my next tesla coil.
 RB> I have a few questions about my proposed secondary.
 RB> 1) I am planning to use a piece of ?sewer? pipe.  It is      
 RB> about 1 foot in diameter and about 5 feet long.  
 RB> Questions:
 RB> 1) L/d ratio is about right - no?

No. In Tesla coil secondaries 8 inches or larger in diameter:
the actual winding length of the secondary should not exceed the
diameter of the coil form by more than a factor of three. In fact
a 3:1 aspect ratio (L/D) is perfect for this coil form, so figure
that the actual coil winding will be about a foot in diameter,
and about three feet long. You will only need a couple of extra
inches of coil form length beyond the length of the actual
 RB> 2) The pipe is made of "plastic."  I know that's not very 
 RB> specific - which is why I am looking for help.  There is no
 RB> printing which says: ABS or PVC or anything else. All I can  
 RB> say is it's green and "plastic." Anyone recognize what I'm   
 RB> talking about?

Sounds like green PVC drain pipe to me.

 RB> Is the material know to be good/bad?

Frankly, it sucks. I use it though, as do a lot of others. The
pipe must be sanded smooth with some #150 emory paper. I wet
sand. After wet sanding I dry the pipe under a heat lamp. For a
pipe this size I would dry it for several days. Then the bare
plastic pipe is sealed with two-part epoxy paint or clear
polyurethane sealer. I put on several heavy coats and let it dry
a few days before actually winding the coil.

 RB> 2)  A while back, I got a whole lot of Litz wire. (Surplus   
 RB> so almost free.) Has anyone experimented with using Litz     
 RB> wire for the secondary? 

What I have read says it's good, but I have no first hand
experience with this type wire.

 RB> I tried it in one of my smaller coils  (3 inch diam, 12 inch 
 RB> long) and compared it to a coil of exactly the same form     
 RB> factor - but wound with straight magnet wire. There was no   
 RB> perceptable difference.

Then you have more experience than I have here. I will tell you
that a 3 inch diameter coil does not resonate efficiently enough
to be a good test coil for this wire. 

 RB> So, before I start winding a few thousand feet of this onto  
 RB> the big coil, I'd like to know whether I'm doing a) a good   
 RB> thing b) a stupid thing c) it doesn't really matter thing!
 RB> I figure, if nothing else, the  'cloth' sheathing will do a  
 RB> great job of absorbing the polyurathane that I normal coat   
 RB> my coils with.

 RB> comments???

How many turns per inch do you get with this wire, and how thick
is the layer of cloth sheathing that is holding the wire
together? Also, is this wire all parallel strands in the sheath,
or are the strands interwoven with each other?

Richard Quick

... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12