The hydrofoil project

[Ayydan]

Time for some "white picture"

Painted. Need to full the gloss a bit (apparently matte cuts water better) but it looks too good to take sandpaper to it

[Ayydan]

I guess the matte thing is from creating a boundary layer of turbulence or something?

It's got something to do with a boundary layer. I guess the surface tension is too high with a glossy finish

Well, the foil holds up just fine. The board on the other hand.... The whole top is under tension and it was only 4oz of fiberglass, so that split right in half. Kevlar held it together to get it out of the water.

Good news: I've already started on another board

[Jersey]

Well, the foil holds up just fine. The board on the other hand.... The whole top is under tension and it was only 4oz of fiberglass, so that split right in half. Kevlar held it together to get it out of the water.

Good news: I've already started on another board

Nooooooooo

No printing in this one, so it's diverging slightly off the topic of this thread, but it's still a foil.

This is v3 'woody'. Solid walnut core, two layers of carbon at the root and then two layers of 4oz e-glass over the whole thing. Hand layup because my vacuum bags all sprung leaks.

suuuuper thin aquila9.3 that I thinned slightly, big ass wingspan and high AR. Flat wing because wood, so it'll be a little bit too intrinsically stable, but hopefully the flat rear stab (also pictured) adds enough instability to make it maneuverable. The intent with this wing is super efficient surfing, and maybe some pumping or wingfoiling if I ever get into that.

I'm putting the full load on 3 m8 bolts, and I'm slightly concerned that I'll have issues breaking the countersunk holes where the bolts go through, but it was much easier than trying to flatten the top or build some sort of cradle, which would have just increased complexity.

If you look close, you can see the branding mark. Hoping it comes out in the top coat of epoxy.

I'm posting the following in preparation for having this site finally indexed by google.

The slingshot mast bolt spacing is 2 inches exactly. Despite the fact that the entire thing is metric, they decided to go with this. Also the counterbores are a frustrating 13mm (I think). 1/2" isn't big enough, so I had to commit a cardinal sin and cut aluminum with a 14mm forestner bit.

Well, it's alive. It flies great, I like the lift profile, and as expected with the higher aspect ratio and thinner profile, it stalls _hard_.

Foils need anhedral - it's really hard work whipping around something that's so intrinsically stable, and it's definitely going to cause me to chuck my slingshot foils trying to turn them, but it's really good foil practice.

This one was designed in CAD before being copied in wood, so I've already modified it slightly with anhedral, more wing area (more bigger = more better), and will be fixing up the disaster that is the countersunk mounts. It'll print on an Ender 3 in 4 parts in one go, and I'm still figuring out a good way to place the spar.

tl;dr weeee!

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[Ayydan]

looking awesome man! Glad to see video embedding is working haha