Lay up...

A two-part mould was created from each plaster ring. This view shows the top part of the mould.

The spokes are corrugations made from strips of foam. These have been placed between the layers of fibreglass to add extra strength. The mould covers the entire ring, plus around two inches of 'flat' onto the baseboard.

Two inches are also added to the other half of the mould, so that the two mould halves can be bolted together.