This is my toroid I made "wow what a pain in the butt". Here is how I made it. First cut two 0.5"
thick plywood circles 4.5" in diameter than sand the edges down to 8degrees. Next drill
a 0.25" hole in the center of each disk, and bolt the disks together. Then get some 3.375"
diameter aluminum flex duct about 2' 11" and wrap it around the disks so it fits between the groves.
Tape the end together securely with aluminum tape, and unbolt the disks. Get some spackle and cover
the entire thing with it evenly and make sure you cover the whole thing. Let it dry. Now here is
the tough part, sand the whole thing down evenly. Next paint it with spray paint, let it dry. Cut about
40 pieces of the aluminum tape to 1" wide and 11" long, its easy to do, if you make a jig to
cut the tape 1" wide. Next wrap each piece around the painted, spackeled flex ducting, after your
done with that coat the 2 plywood disks with aluminum tape and put them in the toroid and bolt
it together. Your now finished, be very careful it is very fragile, but I feel it is a
good performer. Have fun.

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