Re: Small toroids

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

Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 4/14/03 9:18:03 PM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:

>Hi Everyone,
>
>Has anyone out there made toroids as small as 8"OD from 3" drier duct?  I
>have spent half of the afternoon trying to fashion a decent joint, and
>after failing to join the two decently, decided to make the joint with
>masking tape, figuring I could cover the whole thing with aluminum tape
>anyhow.  I have already wasted a roll of tape trying to make a smooth
>surface, and I am very close to jumping on the whole darn thing.  Any ideas
>on how to make a decent splice without covering the toroid with tape, or
>how can I get a decent finish if I do tape it?


John,

I've made ducting joints that are almost invisible by cutting the ducting
close to two of the ribs at both ends, then cutting across the ribs as
needed.  This part that is cut across the ribs (an irregular area) is placed
at the inside of the curve, where it doesn't show and doesn't affect the
sparks.  This was a 3" x 10" toroid.  I cut a  piece of wood to a special
shape.  It's like a disc, but the edges are slanted so it gives the joint
the same curve as the rest of the toroid.  If a simple disc is used, it will
tend to make the joint straight instead of curved.  This special wooden
disc is then glued into the toroid to hold the ends together and touching.
Sometimes I place tiny nails into the wood through the metal.  The heads
of the nails fit between the ribs, so they don't stick out and don't show
very much.

John