Step 17: Sphere
Take your time and cut slowly, the woven carbide disks worked best.
The first time I fired mine up it worked but had allot of sparks jumping from the bottom of the sphere, to solve or help this problem I fitted a copper ring for the sphere to sit on. This will fold the charge back up to it. If you dont have a pipe bender tape one end of the pipe shut, fill it with water and freeze it that way you wont kink it wile hand bending it.
After I got the copper ring bent in a circle I cut it and clamped it, so it could be soldered with the torch
I also cut several more 1/2 inch tall rings off the coupler and put them on the column, this keeps the voltage from creeping down.
Also make the sphere sit as high on the column as you can without losing contact with the comb inside, my sphere is around 4" down the column.