Thanks for the suggestion. The wing_bot suggests the mh38, but the difference for the H105 in drag for the same lift is relatively low.
With the benefit that h105 seems to be less sensitive to profile imperfection, right?
I do not think so.
The camber profile is really hard to get right.
Advantage is how it is a thicker profile, so easier to build a rigid foil with.
For a beginner pump foil, I would choose a profile with a slower max efficiency speed than 28km/h (H105). Would be good to be able to reach that max efficiency speed, 28km/h is (too) fast for pumpfoiling, at leas for a beginner. Around 20km/h seems more realistic.
I have the gong trail xxl and i love it for dockstarting, with no electronic assist. No idea if it is suitable for an efoil. I havent seen any efoils with a wing that large
Also, the amount of force these foils take when pumping is a lot. From the outside it looks smooth, but when you pump on the foil you can tell that the metal underneath is being strained.
Gong actually recommends a titanium fuselage instead of aluminum for wings over 100cm wingspan. The metal takes a beating
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No just efoil mode 
i’m not building an efoil… but just a pump foil!
btw someone can help me to point me out a place where i can get the nuts and bolts for mast board side and fusolage side and the bolt to fix wing and stabilizer?? i dont even know how they are called. i guess they neeed to be stainless steel that’s for sure but what diameter and lenght? and the shape of the head…
does anybody know a place to get this type of thing?
Hi, I have build 2 wings, they both fly and I can dockstart them, BUT they are waaaay worse than a bought one. First wing would kind of lose lift during turns and just slip to the side. Second wing the angle was sleightly off and the wing would only go right turns. It was super hard to ride since only right turns were possible. After fixing that it was better, but still very unreliable. Pumping this wing is not fun, you can never trust it.
If you didn’t learn to pump yet, get a a second hand wing and learn dockstart first. It’s Lready hard to learn, with a diy wing it’s gonna take at least twice as long.
Think of all the angles that can go wrong, a1 degree fault can compromise the performance very hard.
Despite that I would recommend molds apposing to printing a wing and laminating it. It lets you get the dimensions right.
I made several backwings, those are a good starter! They are quickly made, they usually work fine . Maybe buy a secondhand pump set up and start making backwings
The nuts to secure backing to fuselage are called querbolzen mutter (in German, lovely word).some brands also use them to make fuselage to mast
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I have CAD on a whole setup and a few different wings. Ive built everything board, mast, fuse and wings. If i were to do it again or get a new setup i would get a gong v2 baseplate+mast. and just build a fuse and wings. If you 3d print cores and reinforce with fiberglass you can save quite a lot of money, especially if you plan on building multiple of them. Printables CAD
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Instead of buying them, you can design and make a few bolts and nuts. This will serve as a good starting point before assembling the wing.