Composite Manual

This manual is for laminating the girder underneath the cockpit sole of the Shaw 550. The girder runs on the centerline of the boat from the transom to the centre case. The girder is made of 8mm thick foam with a density of 80 and needs fiberglass on both sides and this manual will explain the stack and the steps on how to laminate the girder.

What you would need to laminate the girder:

·         Space to work in

·         A clean surface to laminate and vacuum on

·         Containers to mix the resin in

·         Some latex gloves

·         respirator

·         Mixing sticks

·         Brushes

·         Squeegees

·         Z105 epoxy and hardener

·         Vacuum bag

·         Vacuum tape

·         Vacuum pump

·         Mesh

·         Perforated plastic

·         Peel-ply

·         EDB 240 fiberglass

Steps:

1.       Make the girder to fit and it is always a good thing to leave it longer. You can always take more off but you can’t put it back. Make sure the surface of the foam is clean and dust free without any nibs on it. You wouldn’t want anything under your laminate that could cause delaminating or damage the fibers.

2.       Find a space to work in and a clean smooth surface that won’t affect your vacuum

3.       Both surfaces needs to be fiberglassed so everything can be cut twice. The fiberglass, peel-ply, perforated plastic and mesh needs to be cut to size and can be bigger than the girder itself and be cut off later when the resin has cured.

4.       The stack will be as the following: mesh ,perforated plastic, peel-ply, fiberglass, girder,  fiberglass, peel-ply, perforated plastic, mesh and then the vacuum bag over the layers on top. In order for the stack to be laid out the girder needs to be glassed first with resin.

5.       Wear your respirator and latex gloves when mixing up some resin with 4:1 ratio of resin to hardener and mix with a mixing stick for about 2minutes until the resin and hardener is fully mixed up.

6.       Apply resin to the girder by brushing it on or just pour some out of the container and spread it out with a squeegee  to enable the resin to saturate all the pores of the foam. Now the fiberglass can be laid on the girder and then soaked in resin or it could be presoaked  out with resin and then laid over the girder. Make sure all the fibers are wet and there is no bubbles under the glass by using your brush or squeegee . (do both sides)

7.       Peel-ply can  be laid over the glass and worked out smoothly with a squeegee to make sure the glass is work out flat to take the shape of the peel-ply. (do both sides)

8.       Now the girder which is glassed and with peel ply on both sides  can be laid on the stack which is the mesh and perforated plastic. Then on top of that the other piece of perforated plastic can be laid on and the mesh.

9.       Vacuum tape can be stuck down around the girder and make sure it is nowhere near the wet resin because it will not stick

10.   The vacuum bag can be laid over the stack  and start sealing it to the vacuum tape. Also make ‘darts’ in the bag to allow the bag to expand if it needs to but for the girder it is not really necessary because it is flat. Make sure you have plenty of bag. It is always good toe have to much than too little.

11.   Once the vacuum pipe is sealed in and the bag is sealed up to the vacuum tape, the vacuum pump can be turned on. Once the air is being sucked out of the bag it is possible to find leaks so you should listen carefully by putting your ear close to the bag to listen for leaks. Find them and close them to get a good vacuum.

12.   Once there is a tight vacuum and silence with no air escaping into the bag your job will be complete and leave your composite laminate over night for the resin to cure

13.   When the laminate is cured the bag and plastic can be removed with all the excess resin squashed out onto it and the peel-ply can be removed to show the smooth laminated component