Re: Toroids

To: Tesla List <tesla-at-poodle.pupman-dot-com>
Subject: Re: Toroids
From: Kristian Ukkonen <kukkonen-at-cc.hut.fi>
Date: Wed, 6 Nov 1996 11:38:44 +0200 (EET)

On Sun, 3 Nov 1996, Tesla List wrote:

> 	You need dead soft aluminum (1100 or equivalent), a good
> form, a powerful lathe, and lots of skill.  There are lots of
> local spinning shops, and one could probably get advice and
> material there.  Don't think they's worry about the competition!

Hmm.. Why would it have to be that difficult.. 

Commercial big shaped are manufactured by detonation-shaping as well -
this means basicly that you meed to manufacture a "mould" of the shape
(toroid) and then attach a Al-plate on top of the plate, suck a vacuum
between plate and plate and then immerse this to your swimming pool. Next
one places a detonation device on top of the assembly and as it detonates
the shock-wave will deform the plate according to the shape of the mould -
this works when immersed to a fluid like water.  This is a common way of
making, for example, paraboloid-dishes. Of course, perhaps not too
applicable to the ordinary 'coiler - but for the dedicated.. :)

Another idea would be to make the mould like above with the plate
on top of it and vacuum between them and then start heating the plate
while still keeping the vacuum pump operating - outgassing etc. requires
this to maintain the vacuum. As the metal softens it should deform
itself to the mould by the "pull" of the vacuum.. I'd do this inside
a good oven to get even effect. This method is commercially used
at least for plastics. 

Just some ideas,

  Kristian Ukkonen.