Re: Home-brew Capacitors

To: tesla-at-pupman-dot-com
Subject: Re: Home-brew Capacitors
From: Mark Finnis <mefinnis-at-medicine.adelaide.edu.au> (by way of Terry Fritz <twf-at-verinet-dot-com>)
Date: Tue, 15 Dec 1998 17:08:38 -0700
Approved: twf-at-verinet-dot-com

At 22:48 14/12/98 -0700, Steve Young wrote:

>
>Bottom line - building caps is a major undertaking.  If people discover
>better ways to do it, please share.
>

Currently shifting house so the TC stuff is packed-up till Feb99.

However, have been doing research and recently got inspired!

Contacted a car battery manufacturer to source some of the plastic cases
they use.  Couldn't sell any to me, but gave me a number as a sample.  (you
need a manufacturer, not a distributor)

These are 'square' rectangular boxes with 6 cells set-up in a perfect
manner to build a 6-series vertical flat plate cap.  Initial calcs suggest
should get 0.025 uF per "car battery".  Vertical plates will avoid need for
vacuuming.  Ready made inspection cap-per-cell facility allows checking oil
level & replacement.

Next problem is aluminium flashing is too thick (0.3mm or 12 mil) and
wastes space.  Aluminium foil is too thin (0.01mm / 0.5 mil), tears easily
and has too high an intrinsic R value, especially for point connection
(this includes thicker "caterer's packs", which are only 0.012mm cf normal
0.010mm).

Found a place which makes the foil "cake/pie bottoms".  They have foil from
0.045 to 0.090 mm (0.15 to 0.3 mil) which they buy in 1000 kg rolls (no,
that isn't a misprint !!!!).  They will sell me the end of a roll at
whatever weight I want.  This is a perfect thickness.  Thin enough to cut
with a paper guillotine but thick enough not to tear and allow a more
substantial electrical connection.

All in all, this will take a lot of work but the end result should be
"near-professional".   I will post later & let you know, but I think this
has some potential.

cheers,

mark

Mark

http://www.cobweb-dot-com.au/~dkfinnis