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Re: Cap Experiments and now less ??



Tesla List wrote:
> 
> Original Poster: RWB355-at-aol-dot-com
> 
<SNIP>.
> 
> Last experiment I did was to take a piece of the thin and of the thick
PE. The
> thin stuff is really clear, where as the thick stuff is slightly milky. I
> ignited both pieces and observed. Both smell almost the same while burning.
> Also the way they burn (yellow, slightly sooty flame) is the same. The thick
> stuff feels "waxy". The clear stuff feels a little different. It doesnīt
quite
> have the same "waxy" feel. It feels more like Saran wrap, but it doesnīt
stick
> to itself like Saran wrap does.
> 
> Now I know:
> a.) my new experiment did give me the correct values.
> b.) my HB TC programing was okay, too.
> c.) I CAN build my caps with the thick PE sheets.
> d.) I wonīt use the thin stuff for my 8" coil cap.
> 
> I donīt know:
> 
> a.) is the thin stuff really PE?

Probably NOT, since it seems to have much more dielectric loss than LDPE
based upon the powered-up experiment you performed. You may have
something similar to Saran wrap (which is often Polyvinylidene Chloride,
and which has his a high dielectric loss similar to PVC)...

> b.) if so why do the results still differ ?
> c.) why is the "effective" dielectric K of the thin stuff less than 1 (K of
> air) not really careing what the stuff is made of.

The combination of entrapped air and increased thickness?

> All caps built with the thin PE get really, really hot. In fact I have
had two
> (one was even tested under oil !!) that have gotten so hot, that they have
> melted!! They got so hot that I burned my hand (after 5 min of cooling time)
> while unwrapping them, to see why they had died. 
<SNIP>

This definately does NOT sound like LDPE...

> On the other hand all caps built with the thick poly run and stay almost
cold.
> Even on longer runs. MOT input power (full open at 9.6kV and 700mA)
didnīt let
> them get too warm either. My power cord runing the 4 MOTs got warmer than
the
> caps. Run times were clocked at about 5 minutes.
> 
> My conclusions are you canīt use the pretty thin poly (if that is what my
> stuff is) in a homemade cap. 
<SNIP>
> 
> Reinhard

Thinner LDPE should work, if you can get out the trapped air. Some
coilers have even used thin LDPE baggies for their homemade caps. The
caps I use have multiple sheets of 4 mil LDPE. 

The thin material you have is almost certainly not LDPE - what was the
original use that this material was being sold for? 

-- Bert --