Greener Surfboard

I made a twin-fin “fish” with Greenlight’s 6'6" deluxe kit. They've got kits ranging from 6'0" shortboards to 9'8" longboards. Whatever style you make, it's a big help to keep a similar board on hand for reference.

Download a surfboard outline template from Greenlight, or make your own by tracing a favorite board.

Print out the Greenlight template and tape it together on the numbered marks, then cut out the completed curve. You can use it as is, or transfer it to heavier kraft paper or cardboard.

Glue the blank halves to the stringer, as flush as possible.

Trace your template on the bottom and saw it out. If you're making a swallowtail or other delicate tail shape, don't cut that out yet (it's fragile).

Now clean up the rails, squaring them with 36-grit sandpaper on your 12" sanding block.

CAUTION: Spare your lungs and wear a respirator or particle mask when sanding EPS foam or epoxy.

Plane down the stringer where it rises above the foam, then use your 24" sanding block to level the foam and stringer on the bottom and deck.

For a thinner board, keep sanding with your 24" block. The pros use a power planer, but you're likely to lose control and mow too much foam. I recommend going slow, using the sanding blocks.

For steeper waves, you can put more “rocker” curve in the bottom. For easier turns, I put some “vee” in the bottom, at the tail. This helps the board to roll from rail to rail when you're turning.

Following Greenlight’s diagrams, draw rail bands with a marker. Use the rasp to bevel the foam between bands: bottom bevel, deck bevel, then a second deck bevel that bisects the first.

You'll leave the rails' bottom edges sharp in the tail (more bite for turning), but round them off farther forward (more forgiving).