Hi guys,
Has anyone used a foilmount for their efoil project?
I am using this kite race board
At the moment I am trying to find a local shaper to glass in the other option which is a box
Fred is using same board as you. Maybe he has some info on how to easy mount the mast.
Hi Guys,
Yeah i added 2 US boxes with slinghot base.
I recommend you to add one or two carbon layers, if not you will pull out after first ride (that happened to me ;=)).
I will post some photos.
I’m considering using a FoilMount as well and would also love to hear if anyone has first-hand experience with them. Here’s another video…
Strain on mast mount on efoil is higher than regular foil. It might delaminate the board, some guys on the forum have tried without success.
A cheap way is to use 4x threaded rods through the board with reinforcements on both sides.
Interesting stuff, thanks for the info and for sharing the pics. They look pretty strong and a friend of mine has successfully used one on his sup for surfing and for towing behind a boat.
I would be interested in any first hand experiences anyone on this forum has had, either good or bad
If the board is in good shape , i will try it … For my board i use 4 rods and 2 plates in order to have the correct angle for the mast
Every else for the box plate , cooling system … I use high quality adhesive ( nitto) and it worked very well so far
I know guys in NZ that have lost foils off the bottom of SUPs using these. Luckily they were recovered OK. The problem they had was if there is any minute amount of rocker or concave in the board at the mounting point, they would fail. They might be OK for small kitefoils and boards, but I wouldn’t trust one with the weight of an Efoil.
If one was going to work, it would work on the board you have. Its very flat. I personally would bolt through that board and get the forces spread across both the bottom and top laminates.
Seems to me the strain on the mast and mount on an efoil might actually be lower than that found on a kiteboard, surfboard, or board being towed. The aforementioned three have forward resistance through the water pushing the mast and foil back. But an efoil also has an opposing force via the motor thrust. Wouldn’t that actually reduce or offset the backward force? Or am I missing something?
I agree that this leads to a slightly different loading of the connection, but i feel like it’s not what will decides if it breaks or not:
Overall i think the highest loading that stays applied for a while on the connection happens when kitefoiling, when you edge hard upwind in windy condition (that’s the only moment when i broke a foilboard, you can feel it in you legs that the stress is going up 
(that kind of loading will load a lot the back bolts, and tend to weaken the board at the front of the mounting plate)
However, the connection is also very stressed when you crash, and there are 2 types:
- crash because the wings breach the surface and you go down: the foil pointing down will pull toward the bottom of the water, and the board starting to touch the water will tend to lift its nose.
- crash because the foil hits the bottom.
Here the second case feels the worst as a lot of energy has to be dissipated in a very short time in case of hard stop.
As our e-foils are way heavier than other boards, it means even more energy to dissipate…
Sorry i’m not bringing actual solution, just more reasons to build as strong as possible.
All good points. And we definitely have more than just the foil to lose if the mount breaks and everything goes to a watery grave. That said, I imagine the foil/motor, etc would actually stay attached if the mount broke because of the connecting wires.
Hi fred. Where can one get those rails or “US boxes” as you call them? Cheers.
Foilmount: a bad idea if the outer skin of your board is not made of a thick sandwich skin - delamination in sight …
https://www.seabreeze.com.au/forums/Stand-Up-Paddle/Foiling/Foil-installation–Be-careful-
http://www.efoil.builders/t/custom-boards-mast-mounts/472/15
For a dedicated efoil board, rails are a bit overkill since you are strapless and the cable hole is fixed but if you still want them (90mm spacing) here is a useful link:
US boxes reinforcement: https://www.standupzone.com/forum/index.php/topic,32837.0.html
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