As promised, here is my take on DIY foil parts manufacturing. I hope this long post will give some of you idea on how to make your own parts and maybe start some collaborations on foil development. Grad yourself a nice drink and enjoy!
I have first experimented with all 3D printed parts, vacuum laminated with carbon fiber. The entire foil system came out relatively good, yet the mast was not rigid enough for my taste, despite the 10+ layers used on each side. Getting the mast not to twist during vac lam was also a challenge, and I quickly abandoned making my own masts until I find a better technique (more at the end of this post).

So, I recently grabbed a mast and fuselage from Blue Planet and I am building my front wings, stabs and mast plate adapters around it. These parts are done using a combination of 3D printed molds, silicone molds and 3D printed skeletons.
For the mast plate adapter, I basically design the part in a CAD software using the dimensions of the Tuttle. Then I 3D printed it, made a silicone mold of it and then used carbon fiber chopped strands and precisely cut patches along with epoxy resin. Finally I routed the back side of the harden part and voila!


One of the main advantage of the Blue Planet design is that it uses a "keyed" connection to secure the wings in place (a la Armstrong), providing a super secure and strong coupling. However, that created a challenge on my end, as I could not just 3D print the "female" part of that key for the wing. That's where silicone molding helps again, as I can make a CF/epoxy version of that part, glue it with the rest of the 3D printed wing and vacuum laminate everything with CF. Below is an example my HS1850 copycat I recently made with this approach.



I am leaning now toward full carbon parts and used the tail to test some "new" concepts. Basically, I am making 3D printed molds of the tail and then add CF panels with epoxy and epoxy/filler mix in it. It works fine, however, not destroying the mold is pretty difficult, as the plastic can easily delaminate and break apart. Using the same technique as described above for the front wing female key part, I have made a tail wing adapter so I can change its the AOI with shims.

So were do we go from there? After a year of experimenting with 3D printed parts, I can safely say that it is not an option for the mast for sure. It works fine for the wings, especially if you want quick prototyping, but full carbon parts are obviously far better. This brings me to the new tool I am putting together in order to make my own molds (first in MDF and eventually in aluminum): the big CNC. I hope to get my first mast be the end of the year. Stay tuned!