Re: Flat Coils

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

Original poster: "rheidlebaugh by way of Terry Fritz <twftesla-at-qwest-dot-net>" <rheidlebaugh-at-zialink-dot-com>

John I use teflon or 1/2 in LDPE to hold the sides.I use a fiberglass or
bakelite back plate. I then run my wire through a cup of resin and bond the
wire together as I make my coil. I can use no back plate, but that is not as
strong. When the resin hardens every thing stays in place. Plexiglass is a
bad choice for your winding coil form.DONT pull the wire to tight. It will
bunch up even with the best molding form. Make your molding form thick.
    Robert  H

> From: "Tesla list" <tesla-at-pupman-dot-com>
> Date: Thu, 14 Feb 2002 21:15:50 -0700
> To: tesla-at-pupman-dot-com
> Subject: Re: Flat Coils
> Resent-From: tesla-at-pupman-dot-com
> Resent-Date: Thu, 14 Feb 2002 21:24:44 -0700
> 
> Original poster: "John Tomacic by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <tesla_ownz_u-at-hotmail-dot-com>
> 
> All these postings about flat secondary coils made me take a quick look at
> the inductance of a flat coil and compare it to a helical coil I already
> have.  Surprisingly, the inductance of the flat spiral coil is 60% higher
> for the same length of wire. In this case the length of wire is 1478 feet.
> Since the wire resistance is the same for both coils, is it safe to conclude
> that the Q of the spiral would be 60% higher seeing that Q is proportional
> to XL/R?
> 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.
> 
> 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.
> 
> John
> 
> 
> 
>> From: "Tesla list" <tesla-at-pupman-dot-com>
>> To: tesla-at-pupman-dot-com
>> Subject: Flat Coils
>> Date: Thu, 14 Feb 2002 19:15:32 -0700
>> 
>> Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>"
>> <davep-at-quik-dot-com>
>> 
>> 
>>>> BTW -  One can ground the center and use the outer windings as the
>> high
>>>> voltage ends...
>> 
>>> Or vice versa, as in many of the Tesla patents.  He clearly was
>>> intrigued by them, but don't remember seeing any pictures of apparatus
>>> he built using them.  Has anyone?
>> 
>> pix in the Colorado Springs notes and 'Experiments with
>> Alternate currents of High Potential...' (or whatever
>> the exact title,  Not clear which were Secondaries,
>> which probe/test coils, perhaps.
>> 
>> One interpretation of the Colorado Springs notes argues
>> that the 'primary' in some/many pix is a single turn
>> (thus flat) down near the floor....
>> 
>> best
>> dwp
>> 
>>