Re: Flat Coils

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

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
> 
> Original poster: "John Tomacic by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <tesla_ownz_u-at-hotmail-dot-com>
>...
> If so, then there is an advantage to using flat spirals as secondaries,
> especially in magnifiers where it would be easy to feed the secondary from
> the centre, and have a toroid around the outside circumference of the
> secondary.

The idea looks interesting.
 
> Also, I have an idea for winding the flat spiral, however, I still need to
> try it out to see if it works: Place 2 round plexiglass discs close
> together, separated in the center by a round spacer with spacer thickness
> equal to wire diameter and spacer diameter equal to desired inner diameter
> of coil.  Wire would then be wound around the center spacer by spinning the
> whole "sandwich", and the plexi disks would keep the wire flat as the spiral
> is built up.  One of the plexi disks could have 1/2 inch wide radial slots
> in it to apply glue to hold the wire in place after the disc is removed (or
> both disks could stay in place after finished). The spacer in the middle
> could be a pvc pipe of desired diamenter and the plexi disks would have a
> hole of the same dia as the pipe so that the discs could slide over the pipe
> to the desired separation.

Plexy disks would almost surely be not flat enough for precise work,
unless
you use thick plates. Maybe thin plexy disks that will stay there,
supported
(during the winding) by plates of a more rigid material out of them. 
Maybe even wood plates. The spacer can be the first turn of the wire
itself.
The wire can be made to pass through a pool of molten wax, or maybe hot 
glue (excellent insulator), before going to the spool.

Antonio Carlos M. de Queiroz