For the skirt I needed a large silicon mould since I wanted to manufacture it in one piece.


Basic structure was again made from wood.

Polystyrene sheets are difficult to bond together under load and so I sanded these polystyrene sheets on the inside and fixed these with household adhesive (Pattex). Then the next day I bonded it permanently from the inside using thickened resin.

The struts were manufactured from resin.

I tried to manufacture this mould with as little silicon as possible. At the beginning I laid on a thin silicon layer with a brush.

For further layers I moved the part into a vertical position again and let it rotate, in order to prevent the silicon from running off.

This shows the finished supporting mould with inserted silicon mould. The attempt to work with as little as possible silicon on a larger mould did not prove that successful. The master model was perfectly cast but handling this thin walled, unstable mould is much more difficult than with thicker walled silicon moulds. My tip: Do not try to save silicon at the wrong end of the process.


The result is a very light GRP skirt.