doing it on the beach (repairs that is
) is no different than doing it in the garage except that you get a better tan. Before the season started we used to apply two layers of f-glass to the keels. We laid out 3 inch wide strips the entire length of the keel and applied resin. Just after the first layer cured we applied the second layer.
Buy a fiberglass repair kit with cloth from your local auto repair place. Buy more cloth - available separately. The basic kit has enough resin to do two hulls if they're not too bad. You need SHARP scissors to cut the glass with a minimum of loose strands
Buy a set of "sureform' files and some 100 grit sandpaper, some 2 inch wide masking tape, a couple of throw away bristle paint brushes (4 if you are doing two layer on each hull and a Sunday paper
Flip the boat over - (assuming mast is down :0)
Use the masking tape and news paper to protect the hull from drips and "define" the area that you want to repair.
Cut 3 to 4 inch wide strips of cloth to cover the repair area.
Follow the instructions on the resin to mix- it is better to put too little hardener in than too much- it changes VERY quickly. Less hardener gives you more working time - too much less hardener makes the repair soft. Be a baby bear and make it "just right".
QUICKLY brush a thin layer of resin over the damaged area using the bristle brush.
QUICKLY place the cloth onto the resin and work into place with the spreader that came with the kit. Gently, but firmly - too much pressure shreds the cloth. Go one direction and do NOT go over where you have just been. Stand back. Crack a cold one. Do the other hull.
When this layer is cool and hard to the touch you can apply a second layer.
File and shape with Sureform files and sandpaper.
Crack another cold one - go sailing...