This is the method in the appendices of my plans for making excellent and accurate foils (centreboard, leeboard, keel or rudder blade) which all add way more performance for not so much effort and zero cost difference.

A Homebuilt Centreboard, Rudder or Leeboard can look like this

This photo is of the epoxy coated foils ready for sanding with sandpaper around a block ready for their final coat/s of epoxy, varnish or paint.

Preparation – Cutting glass and hanging the foil.

Cut one piece glass to do both sides by passing over the nose. If you used the templates in my plans you will have a beautifully smooth shape timber blank to glass. There can be no bumps around the nose area.

put screws or long nails in the ends so you can hang it up so that it pivots with the nose upwards automatically. Often I use just one about 50mm from the leading (front rounded) edge so it will hang with the leading edge up.

use a plywood squeegee – plywood about 150mm long with a straight edge. Sand the corners and edges slightly so they are a little rounded and won’t catch on the threads.

Get a cheap 50mm 2″ brush and cut the bristles so they are about 25mm or an inch long. This allows very good control of the amount of resin and also allows you to use pressure inn a controlled way.

Method for glassing Centreboards, Rudders, Leeboards and other sailboat foils

Don’t work in direct sun!!! :)

You can lay it on a flat surface to do the first side but you will have to hang it for the second side.

DONT put too much resin on it. Just enough to make the glass go transparent. You should be able to see the texture of the weave.

Work from the middle towards the ends. and down from the front edge. If you go the other way you will get air bubbles.

Don’t mess with hot resin Ditch it!

If the resin starts getting hot in the tin throw it away and mix up less next time. A preventative for it getting too hot or pour in a tray so there is enough surface area for the heat to get away. Or be quick to get the resin out on the glass and spread it out.

You should be able to see the weave of the glass, don’t try to make the texture smooth by adding more resin.

Filling up the weave with recoating – the wet on Tacky method saves sanding

Wait for the first coat to feel tacky/sticky and put on a second coat. You should still be able to see the weave. Dont try to fill the weave, just a nice normal coat over the whole surface. Start from middle front and work outwards. Squeegee or brush, or just use brush.

When that is tacky then a third coat.

Aim is about ninety percent of the weave should disappear with successive coats.

The Perils of trying to do too much with each coat.

If you try to do it all with one coat … it will be a big mess the glass will float on the resin so you lose the smooth shape and there will be drips and runs everywhere.

That is:

lots of extra work a loss of the original super accurate shape wooden foil you made from the template.

Some Essential Glassing Methods for making excellent Foils for sailboats

Here are some other glassing techniques including the neat double bias method for doing irregular shapes like the ends of foils.

Fibreglassing method 1; small areas eg glass tape or glass patches

Fibreglassing method 2; Double bias tape for curved surfaces

Fibreglassing method 3; Method for large areas eg glassing bottom of hull or foils