Re: Toroid Support

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Parpp807-at-aol-dot-com>

In a message dated 8/19/02 10:03:53 AM Central Daylight Time, Par pp 807 
writes:

> In a message dated 8/19/02 9:33:09 AM Central Daylight Time, tesla-at-pupman.
> com writes:

Resend                                                          
>  
>  > a heavy duty piece of 8-inch flexduc
>  
>  Hi Ted,
>  
>  I don't know if you are referring to the flex duct sold by McMaster-Carr. 
> This is the 
>  ducting that is thick-walled and one continuous piece--no joints to tear 
> apart.
>  I have used it with some luck. A 2.5 foot length stretches to 30 feet. The 
> idea is to stretch it out far beyond the desired circumference, wrestle it 
> into a large "near circle" and join the 
>  pre-finished ends with a suitable insert. After joining the ends, I then 
> push and work the ducting back into the smaller diameter that approaches 
the 
> finished size.
>
> I would not use strips of aluminum bracing unless you keep them below the 
>surface. Even the small panheads I use to join the ends of the toroid can 
become
>a breakout point.  

> Pie pans or pizza pans are good, but they are too small for the larger 
> toroids.
>  So I bot some sheet aluminum and cut circles of a diameter at least two 
> inches larger than the inner diameter of the toroid. Make a rigid wheel as 
> tho the toroid is a large tire.
>  I used Delrin tubing and tapped the hole for 1/4 - 20 bolts. The tubing 
> holds the wheel together. Place the tubes around a circle that brings the 
> tubes in contact with the inner
>  wall of the toroid.
>  Make 1/2 of the wheel and place the toroid duct over the Delrin tubing 
which 
> is now inside the inner diameter of the toroid. Bolt on the top sheet of Al 
> and tighten the whole contraption together. If you do it right-- that was 
> hard for me and took some trial by error--
>  you will get a tight wheel with the properly sized toroid tire.
>  
>  A picture would help.  :-))
>  
>  Happy day,
>  Ralph Zekelman