How to fix the rail of a surfboard

The rails of a surfboard are very sensitive to shock, that´s why I will explain you how to repair it by yourself.

In this case, the surfboards has suffered hundreds of miles on a bike racks rental in Bali, fiberglass is very cracked and soft, and need to be fixed!

Being able to fix your surfboard by yourself is not only a question of saving money, but it´s the peace of mind you will have, as you know that you can fix your board for the next day, so you will not miss a single wave.

1. The materials you need to repair your surfboard

We will repair the rail with polyester resin and glass sphere, because this board is made from polyurethane foam. If it was made with EPS foam, we should use epoxy resin.

For this tutorial we used Solarez polyester mixed with glass sphere. We could also have used Solarez Microlite which is a mixture of polyester resin and glass sphere, or H61 UV polyester resin with glass sphere. All those resins catalyzed by the action of solar UV, which mean that the resin hardens in a few minutes if you put it outside. That´s why you must work in a place whithout any natural light. If you can´t do that, the other option is to use Silmar polyester resin with PMEK hardener. You can make your repair anywhere, while the temperature is between 15 and 25 degrees.

We will need a layer of thin plastic to use it as a template for the rail, you can use an old hospital radiography. We also need sandpaper, thickness 120 and 240 for sanding,  and fine sandpaper 360 and 500 for a perfect finish.

2. Preparation of the surfboard

Your surfboard must be dry, if the foam is wet, you should clean the board with fresh water and let it dry a few days. With a knife and sandpaper, remove the pieces of damaged fiberglass and sand the whole area, so  the resin will have e better grip.

Stick the plastic layer on the lower edge of your surfboard, so you will be able to wrap it around the rail, and use it as a mold.

3. Preparation of the Resin

If using polyester resin catalyzed with UV, make the mixture of resin + microshere, in a place with no UV radiation! The most convenient is to use Solarez microlite, since the mixture is already done.

If using Silmar Polyester resin, you will have to add PMEK catalyst, between 1% and 3% depending on whether the temperature is 15 or 25 degrees celsius.

4. Apply the mixture on the surfboard.

Just apply the mixture in the right place, on the part of the rail you want to fix, and wrap the plastic film around the edge. When the resin is hard, you can remove the plastic film.

5. Sand the surfboard.

With this technique, yo will have very little sanding job, start with a medium 120 sanding paper. You can use a rotary electric sander or manual sanding. When the shape of the rail is smooth, sand with 240, 360, 500 sanding paper, and 500 with water to achieve the same aspect than the rest of you board.