@DIYfoiler where are you based? I have some inflatable boards, but you would still need to build the box (haven’t had time to build them yet, but do have some designs).
In terms of building a box, Sifly have the most simple design with their hatch on their Rider board. A large Lip at the rear and then a single lightweight latch in the front:
I am from Vienna, Austria. Where are you?
I’m in the UK, so easy enough to post to you.
I’m very likely going to go with a Easyfoil TWO board and build my own box for it. The design step I’m most unsure about is the mast plate connection to the board. My idea was a thick aluminium plate on the bottom with threads, that would only get glassed over on the edges to expose the aluminium directly to the water.
The reason for it was ESC cooling. The ESC gets mounted inside a waterproof aluminium case that it going to sit on the other side of the thick plate and should transfer the heat into the water when it gets in contact. In theory that sounds good, but it feels like overkill.
My ESC will be the Flipsky 75100 Pro V2.0, but I’m open to suggestions. The motor will be a Flipsky 6384.
What do you guys think?
I would go with 75200 immediately, more reserve and better reliability for almost the same price
I think 6384 is a bit on the small side, the inflatable boards needs a little more power to get out of the water… I run a 65161 on mine
thanks. the bigger ESC is probably worth it. i selected the motor due to some legal restrictions. can always upgrade in the future… 
any feedback on the aluminium plate? The bigger ESC might not get as hot as the other one i guess
I really like having the plate… easy to mount the mast, simple and effective cooling.
Not sure how much weight it will add… 500-700g maybe compared to carbon plate?
i guess for a first build it would make sense to go with a design like this… The Gong mast plate uses M6 screws for the board connection, right? I was think about getting a 10mm plate in which i drill 8-9mm deep threaded holes. I think that should be sufficient for all the forces of the mast, right?
I still have many left and can send you a few within EU
What thickness did you use and did it cover the entire base section?
I bought the box ready-made from easyfoil… I think its a 5 or 6mm plate, the whole bottom area
In my calculations a 700mmx400mmx5mm plate weighs 3.78kg. the same in carbon is only 700g. So it’s actually a 3kg weight difference.
I thought carbon fiber is ~1.5 g/cm³ while Alu is 2.7 g/cm²
So Alu is 1.8x heavier, in your example (I think the plate is smaller) the Alu plate should be 3.8kg while carbon should be 2.1kg, not 700g??
Here a old video how my box looks: https://www.youtube.com/watch?v=cn1bBH9-ofo
The carbon is a carbon foam sandwich so is not a solid plate.
Makes sense
I have no experience with composites, if that sandwich is enough to spread all mast forces into the surroundning board I guess thats a substantial weight saving indeed.
i’m not planning to do a full cover plate. only embed a 210x140x10mm plate into the bottom. that give me around 2cm on each side to glass over on the bottom side, to its sandwiched in…
Basically run a carbon plate to secure the mast inserts. Then run 2-3 carbon stringers full length. Kinda similar to carbon pump boards other than you don’t need the deck as solid. I’ve been hunting for simpler constructions and may have a good option but need to strength check it first.
