About the process:
I used a 100mm thick XPS (Extruded Polystyrene) insulation panel that I shaped following the templates I have made on Illustrator. I made tiny holes all over the surface to strengthen the bond between the XPS and epoxy. (I hope it will prevent delamination). I also did a sealing coat with epoxy Qcell and silica also thinking it would help with the XPS delamination problem.
The lamination schedule is 4oz on each side + a carbon tape and a 4oz reinforcement patch on the tail.
Then I wrapped everything up in a 2mm cork layer. I did it in 2 times, one side after the other with a vacuum pump. I used epoxy to stick it.
I’ve carved the side bites myself into a set of Aliexpress FCS fins.
I wanted to try cork for its shockproof and grip properties. After some testings, surfing with cork on the bottom doesn’t compromise the hydrodynamic of the board. It felt really easy to duck dive with the corrugated rails. The grip provided by the cork is really comfortable for paddling and also under the feet.
Ideally, I would like to use flax instead of fiberglass and bio-sourced epoxy resin instead of standard epoxy but, unfortunately, these are pricey.
Edit: a few months later it snapped. Don’t do like me, just put more layers. Don’t count on the carbon tape. It’s useless. And also, think about 3mm cork instead of 2mm on the deck for more impact resistance.
cxlso – Cork Surfboard V1 – 2020