Nomad's DIY foil build

[kjorn]

For the foil profile I made a few card templates then used an old hand rasp to shape the wing. Took ages but it worked fine. The core was made out of ply so the layers gave you nice contour lines to follow.

10: Take some wood off with the rasp
20: check the card template
30: Go To 10

[NorCalNomad]

Yup that's exactly what I've been doing. No videos of the shaping, but my front and rear wings are done and I have my mast %45 done. I'm away from the foil until the week after next for business trips but I put up some updates of the shaping.

[NorCalNomad]

...f***...my saw dropped on the thin walls of the fuselage of where the mast slides in and broke it in half... Guess I'll just have to put more glass and carbon right there...

[rynhardt]

...f***...my saw dropped on the thin walls of the fuselage of where the mast slides in and broke it in half... Guess I'll just have to put more glass and carbon right there...

Shit. That sucks man.
This kinda thing happens to me more than I'd like. I just don't publicly admit them.

[kjorn]

...f***...my saw dropped on the thin walls of the fuselage of where the mast slides in and broke it in half... Guess I'll just have to put more glass and carbon right there...

My strut started to split down the trailing edge. I don't think enough epoxy penetrated the carbon fibre in places, then water got in and the wood core expanded a little. So I drilled a bunch of .5mm holes, then forced the split open and poured expoxy in and made sure it came out the holes I drilled. Then I wrapped the lot in plastic wrap and then clamped it shut. It seems to be holding up fine (touch wood)

Part of the joy of a DIY build is over coming these issues and learning as you build. People look at my crappy foil and laugh, but I know in my heart that all those hours of work and trying to build it for a little money as possible by re-using or recyclicng other bits and bobs, making my own clamps and tools... that's where the fun is.

Just keep going! Don't lose heart, take a day to swear and kick the cat a few times, then figure out a solution and keep making!

Good luck.

[NorCalNomad]

Oh this was before I put on glass luckily!

[plummet]

What wing profile are you using for the wings?

[NorCalNomad]

Eppler 874 is one that came up in my research. A big plus since I'm hand foiling is that it is basically a "flat" foil (when given a 2 degree pitch) that doesn't really require any shaping on my concave parts of my wings.

[NorCalNomad]

My strut started to split down the trailing edge. I don't think enough epoxy penetrated the carbon fibre in places, then water got in and the wood core expanded a little. So I drilled a bunch of .5mm holes, then forced the split open and poured expoxy in and made sure it came out the holes I drilled. Then I wrapped the lot in plastic wrap and then clamped it shut. It seems to be holding up fine (touch wood)

I'm assuming you're using the plastic wrap to ghetto vacuum bag parts. How does that work for you?

[kitexpert]

The project looks good. But mast profile is a bit unusual. In hydrofoils I've seen mast is symmetrical, thickest part of the profile is at the center of the chord.

Rigidity in all directions is the mast's main requirement. It may be wiser to do it a bit thicker and wider (longer chord) and of course think laminate directions and count carefully. Small increase in drag of the thicker mast is not so harmful, especially so with first foil for learning. It is difficult to get laminated mast as rigid as aluminium one, because solid metal has same rigidity in every direction.

Carbon makes it possible to achieve stiffest mast, but it needs considerable skill and engineering and costs too. I have seen carbon/glass masts which are not as stiff as aluminium ones. Torsion stiffness is usually the weak point of laminated masts.

Good luck