Toroids

Reinventing the wheel - a neat way of making small toriods

Megatroids - construction of a 48" by 18" toroid - and how to extend it to 72" by 18"

The Triodal - 3 spheres in perfect unity

An Unusual top load

Following others on the list I made my first small toroid using a plywood disc and foam pipe lagging - about two inches diameter I cut a slit in this to the centre and wrapped it round the disc using wire to hold it in place, I then used aluminium tape to cover it all for an 18" by 2" toroid.

The little toroid in action.

My second toroid uses 4" diameter Aluminium ducting - this comes as a 1 meter long tube that can be extended to 3m. I cut two plywood discs 2 foot diameter and then covered one side with aluminium foil - fixed with wood glue. These board were then fixed one inch apart, using a couple of pieces of wood. I then stretched the ducting around this wheel. (I would fix the plywood discs 2 inches apart in the next one. Easier to fit)

I had passed a wire and one of those stretchy luggage rack ties through the ducting to hold it in shape (next time I'll use a piece of chain so that I can easily alter the tension.

It is fiddly to stretch and shape the ducting material - two people would be better.

I had drilled holes though the edges of both plywood discs, about 1/2" in and 6" apart I passed wire though the holes and round the ducting to secure. I also used wire to tie the ends of the ducting together and used Al foil tape to cover over the join, I soldered the wire joints for permanence.

For those in the UK (and else where) the 4" ducting is available from B and Q. RS components have different style of ducting. A toriod based on this can be seen on the Bride of Frankenstien page. The prices given are in UK pounds (multiply by 1.5 for rough US dollar prices).

Ducting Aluminium

214-4714 Ducting,4in flexible,aluminium,3m 9.06

257-9126 Ducting,flexible,aluminium,100mmx5m 14.42

214-4720 Ducting,6in flexible,aluminium,3m 15.76

257-9148 Ducting,flexible,aluminium,150mmx5m 23.69

214-4742 Ducting,8in flexible,aluminium,3m 24.30

257-9160 Ducting,flexible,aluminium,200mmx5m 36.05

214-4758 Ducting,12in flexible,aluminium,5m 55.11

Ducting Fibreglass - would need covering

193-5632 Ducting,flexible,4inx3m 8.70

257-9132 Ducting,flexible,fibreglass,100mmx10m 28.84

193-5648 Ducting,flexible,6inx3m 12.88

193-5654 Ducting,flexible,6inx6m 24.29

257-9154 Ducting,flexible,fibreglass,150mmx10m 39.14

193-5660 Ducting,flexible,8inx6m 36.14

257-9176 Ducting,flexible,fibreglass,200mmx10m 56.65