Building the beams
The mould is built using form ply. It is readily available, is relatively inexpensive and has a smooth surface so the glass doesn't stick (but resin coated plywood will work as well). Pilot holes are drilled as markers for the pins that hold the folding system. The mould is waxed and polished a couple of times. Mould release (PVA) is wiped on with a cloth. The pilot holes are blocked with a small bit of filler (resin and Q cells works well).
The glass is cut out using a battery powered cutter. We found this cutter saves many hours and RSI. Because this job is tedious and time consuming I cut glass whenever there is spare time. This might be a job you could delegate to someone who wants to help.
The first layer is chopped strand mat. This gives the finished beam a smooth finish. There are many consecutive layers of triaxial, unidirectional and double bias glass layered, wetted out and compacted. After a couple of days the beam can be removed after drilling the pilot holes. Because polyester shrinks it is relatively easy to remove. A couple of hardwood wedges and a wooden mallet should do. Epoxy resin doesn't shrink as much as polyester so you may have to use water or water under pressure to remove the beam. (Water dissolves the PVA release agent).
The beams can be trimmed to size using a diamond studded cutting disc in your angle grinder, sounds expensive but they are not.
Building the centre board and rudder
The centreboard and the rudder are both built the same way. Two pieces of 12mm plywood are laminated
using a couple of layers of glass cloth and epoxy resin between.
The boards are shaped using a router and a small grinder with a sanding disc. Then the board is cut to shape. After the
correct shape is achieved the board is covered with glass cloth and epoxy resin. The board is filled and sanded ready for
paint. Centre board, rudder blade and locker doors were painted.
