Board / Surfboard blanks


@Mat Hi Mat, Isaw your videos and build on bunch of topics. Best diy boards I have seen so far for efoils here,Great job! I am wondering if you are using any kind of available templates? I am about to start my first board making and a good template will help a lot.
Also if you share the source for buying big EPS blocks I would be really appreciated.


I didn’t used a pre-made template, instead i created a rough board in fusion, and modified it to get a suitable volume.
Length was constrained by the size of the block and what fits in my car.
Width was kind of free, but the more width the more stable you are before starting and at low speed.
Height was constrained by the size of the batteries plus the extra thickness needed for the box, the battery tray, the cover and a few cm of safety… safety which disappeared somehow during the build :slight_smile:

After that i used a projector to put the profiles on paper. you can also do it by hand by measuring point every few cm from the center line…

For the polystyrene, i found a shop that exclusively sells dummy cakes made of polystyrene, yes, i didn’t even thought that could exist. Called them up and the guy was nice enough to cut me the size i wanted… main issue was to transport them…
They only had 1lb density though… I’d feel more confident with 2lb, but it turned out ok thanks to the thickness of the board…


Hi there Mat what size have you made your board? Thanks Michael.


it’s roughly 1800x600x120 mm
might have become slightly smaller when shaping… :slight_smile:


Hey Matt, Ive just installed my foil. its 3d printed with 3-4layers of fiber and 2 layers of carbon but still feels a little bendy . did you have any bend in your mast or is it extremly ridget?


My mast now is a liquid force alu mast… no bend at all…
But before that i made some with wood wrapped in carbon fiber and you could support it horizontally with both ends on pieces of wood, step in the middle and it was not flexing more than a few mm in the middle. It was for kite-foiling though where the mast gets more stressed than for e-foil.

I think the “mixing carbon and glass” discussion is already somewhere on the forum but the bottom line was: do not mix them: carbon is way stiffer than glass, so as the parts starts deforming the carbon take most of the load, and if it’s not strong enough to take it, then it breaks and all the load now goes through the glass…
Only good reason to mix them is for aesthetic purpose…


I guess you all saw Kyle Lenny pumping hard with his legs to catch the next wave.

Say we would want to also use the board that way. Isn’t that really bad for the board, risking to break it in 2 ? Would it need strenghtening compare to your presents methodology / hardware ?



I’m not sure pumping is so bad for the board… there’s some energy going through, but it’s all smooth.
gut feel, but I think the stress is more important when going upwind hard with a kite or when hitting the bottom …


Hi Matt, I watched your time laps video of building hydrofoil. Very impressive skills. I am very new to glassing and making boards from scratch. Would you mind sharing your method? Like number of layers, layers material, what epoxy you used?
Also wondering How long it should wait for each layers in vacuum to cure? Is it possible to go without vacuum?
Thank you


I was kind of new too glassing to when I started…
all the layers are written in the movie where I used them,
[12oz Double Bias Carbon Fiber Fabric]
[Style 262, 4.8 oz. X 30in. Carbon Fiber Fabric]
[GAO45 4.4 oz. X 24in. Carbon,]

and the resin I use is always the resin research.
for that project, it was: [2070 Infusion Epoxy w/Fast hardener]

during the vacuum it’s always by feeling, better to wait too much than not enough :slight_smile: and kept the rest of the resin in the bucket each time to see if it was cured inside the bag…

without vacuum is ok for the board, not sure for the foil, or you’ll end up with a tick mast I think… an alternative is to compress the layers between some plexiglass plates…

but making a vacuum pump is pretty cheap… either from a salvaged refrigerator compressor or an car AC filling pump …

but before starting, think twice about using a aluminum mast… it won’t end of more expensive, will be stronger and will give you more space for the wires… :slight_smile: