[Prev][Next][Index][Thread]
Re: Sonotube HV properties (fwd)
---------- Forwarded message ----------
Date: Sat, 1 Mar 1997 10:37:12 -0500
From: Thomas McGahee <tom_mcgahee-at-sigmais-dot-com>
To: Tesla List <mod1-at-poodle.pupman-dot-com>
Subject: Re: Sonotube HV properties (fwd)
----------
> From: Tesla List <mod1-at-poodle.pupman-dot-com>
> To: tesla-at-poodle.pupman-dot-com
> Subject: Re: Sonotube HV properties (fwd)
> Date: Saturday, March 01, 1997 12:15 AM
>
>
>
> ---------- Forwarded message ----------
> Date: Fri, 28 Feb 1997 21:40:22 -1200
> From: Ken Smith <ksmith-at-ihug.co.nz>
> To: Tesla List <mod1-at-pupman-dot-com>
> Subject: Re: Sonotube HV properties (fwd)
>
> At 21:12 27/02/97 -0700, you wrote:
>
> >Ed, Greg, and all,
> >I have noticed that a lot of little park playgrounds have these slides
that
> >are made from plastic tubing that is large enough for the children to
slide
> >inside of them. The middle section is a straight section that is bolted
to
> >the curved sections. This straight section would make an ideal coil
form,
> >wouldn't it? I wonder who actually manufactures the plastic sections,
and
> >what they would charge for one? Anyone out there with a tape measure who
> >can tell us what the dimensions (length, diameter) on the straight tube
> >are? I know they are made of plastic with a high insulation value. I
would
> >guess that they are fairly expensive, but it looks like they would be
> >excellent coil forms. Has anyone out there used any of these?
> >
> I have followed this secondary debate with some interest (if only
academic
> <g> - mine is only 4 inches across (and I am talking secondaries here
<BG>))
>
> If you want to wind a big secondary, could you not go open in the same
way
> as the primary. Does there have to be something between the wire and the
center?
>
> My thought was to use 1 inch poly tube as verticals spaced say around a 3
> foot circle with a suitable number of formers up the height of same and
at
> the top for rigidity. Although this would only be an approximation of a
> circle (depending upon the number of pipes) - is seems to me that this
> wouldn't matter. How you would rig this on a jig for winding is another
> matter - but in principle would it work ?
>
> Over.
>
> Ken
> Ken Smith
> Weymouth
> Auckland
> http://homepages.ihug.co.nz/~ksmith
> ksmith-at-ihug.co.nz
Ken,
Tesla wound his larger coils on open forms, and I have seen a number of
Large Tesla coils that use that same method. A great advantage to such
open frame coil forms is that they are much lower in weight. The coil
does not have to be perfectly round, but every effort should be made
to avoid sharp edges. For example, a square coil form would be bad, but
something like an octogon would be much better.
Another method is to make an open frame form and then wrap a thin sheet
of flexible plastic around it, and wind the wire over this plastic sheet.
Some care has to be taken with the seam. That way the thing would be
almost perfectly round, lightweight, and relatively inexpensive.
My reason for mentioning the playground plastic tubes was to point
out the fact that there ARE some big plastic tubes out there for those
who absolutely demand such structural coil forms. I am sure that
they are expensive and very heavy. But maybe for a museum quality
coil they would fit the bill.
Fr. Tom McGahee