A torus (or doughnut) is a very "tactile" object and not too difficult to make
This one has a thickness of 40mm, a hole also of 40mm and a diameter of 120mm
When it is partly finished it must be fitted into a holder (or jam chuck) so that is made first
This holder is made from layers of blockboard with a hardboard securing ring
The blank is about 125mm in diameter and 50mm thick. A temporary spigot is cut
An accurate spigot is formed in each face