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Re: Coil success on first big run - thanks everyone

Bob, Gary and All

I did another big session of tuning today and with the small topload could
only manage an extra inch. I decided to rig up my big toroid (6" minor dia
x 24" centre to centre) and tapped at about 9.75 turns as Wintesla
recommended. I didn't even adjust this during the session and my longest
spark (one or two hits seen) went up to 44". I'd also replaced my useless
primary tank wiring (OFC speaker cable) with some aluminium tape, which
will later be replaced with copper. I was shocked by just how much a
difference a big topload makes! I am well and truly getting into this thing
now and feeling very pleased with myself... I am hoping that coiling is
going to take off in a really big way in this country! I can't wait to show
the thing off either... my Ma and Pa are terrified of the thing but still
fascinated (I moved temporarily out of my London flat as my flatmates
weren't too keen).

Also, I rounded off my safety gaps with a file (per Gary Lau's idea) and
they no longer 'hold' an arc from those nasty sharp edges I had - they now
fire very rarely when I'm close to tune and often if I'm well out - seems
good. I have run as long as 2 minutes so far and still my MKP-based MMC is
only slightly warmer than the air. I'm crossing my fingers on this one....
it only cost about £80 for 70 caps so I may strengthen it later.

I have to find some earmuffs or plugs as yesterday I noticed that my right
ear (the one nearer the sparkgap when operating!) was slightly deafer than
usual - my vacuum sparkgap is LOUD - the bangs are easily *much* louder
than the unenclosed 1000W vacuum cleaner fan which runs continuously on
full power. It's not painful, so I guess it's below 120dB, but I know that
long-term exposure is not a smart idea. 

I will put up details of my MMC and coil on my website when I get around to
updating it (it's been over a year since I looked at it) - I'll publish the
address when I'm done. I have taken a few pics as well - will do some more
tonight.

I tried the CD - frying trick - it was *really* funny to watch the arcs
from the toroid slowly blast their way across the playing suface and see
those little flakes of aluminium form a little fountain as they were thrown
clear! AOL, Virgin Net and Compuserve all ended up as pretty, transparent
frisbees. I have to resist the temptation to do the same to mum's Celine
Dion.... any interesting ideas for other objects to expose?

I have to say a big thank-you to everyone who has given me advice and
information via this list (and to Chip for running it) and have to say that
it is one of the most friendly, civilised and co-operative places on the
internet - if only the rest of it was like that! It's great not to get
flamed for asking a stupid question.... 

Cheers all,

Alex