Re: space winding

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

Hi David,

On 7 Aug 00, at 17:01, Tesla list wrote:

> Original poster: Tesla729-at-cs-dot-com 
> 
> Hi Malcolm, all,
> 
> I have had problems with turn/turn flashovers on several oc-
> casions in the past. I'm guessing these problems stemmed
> mostly from improper design/tuning on my part. IMHO, the 
> turn/turn flashover problem would not be alleviated by space 
> winding without correcting the design flaw(s).I can't argue with
> the fact of higher Qs for a smaller guage sec wire nor am I per-
> sonnally academically qualified to discuss this subject with
> any authority. I do recall reading in J Couture's Tesla Coil De-
> sign Manual that lower Qs are desirable in large Tesla systems
> for longer sparks. I'll admit this does seem to go against typi-
> cal wisdom along these lines, but I would have to agree that
> naturally, you would have to opt for larger guage wire as the
> power level increases.

In case that comment of mine about wire gauge is taken out of 
context I'd better stress that the higher Q with smaller wire 
applies strictly to the following situation: Same size former, 
same number of turns. What I found was that a closewind with 
heavier gauge wire just costs more in wire because any benefit 
the heavier gauge gives is knocked flat by the proximity 
effect when the turns are in closest proximity to one another.
     You can think of a closewind as being a spacewind wound 
with the heaviest wire gauge which still permits a single 
layer wind. I don't claim that Q's above a hundred or so are 
going to make much difference because most losses are in the 
primary gap but I do know from bitter experience that a low Q 
secondary (e.g. 40) is a total dog and will not perform at all 
well.

Regards,
Malcolm