Homemade caps vs. MMC's

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

Original poster: "Craig Fuller by way of Terry Fritz <twftesla-at-qwest-dot-net>" <cbfull-at-hotmail-dot-com>

Hi all,

I have been using MMC's since my very first coil back in 1988.  Some guy who 
had his own electronics shop here in Ohio sold me two bags of 100 caps for 
10 bucks.  I had no idea at the time that they would be so useful.  They are 
rated at .224uF and 1000V each, which is just perfect.  I can make a string 
rated at 45,000V and 0.050uF, and as I increase power, I just parallel 
another string.  The best part is, after 20 minutes of operation, they don't 
even get warm!  I have looked for more on the net just to see how much they 
cost but I can find nothing to match.  What a lucky find.  Maybe I can take 
a picture of their markings in case someone would recognize the 
manufacturer.  Anyone interested?  I don't have a website so you would have 
to put them up on your own.

Also, I never considered building my own from polyethylene and mineral oil 
because as a chemical engineer, I was pretty sure that the mineral oil would 
slowly permeate the polyethylene because of their chemical similarities 
(like dissolves like, for those of you who have not taken general 
chemistry), and eventually, almost certainly, cause the PE dielectric to 
fail.  So I recommend that anyone looking for a cap to use on their coil, 
save yourself the frustration and don't risk using the classic homemade cap 
recipe.  Just  look for suitable caps to make a MMC.  You won't regret it!

Craig