The composites shop I was chatting with showed me a number of MDF molds they use for many shots with 250degF+ cure temps. I do believe they bake the finished molds at elevated temps before using - mostly to dry out any absorbed humidity.
They use Roseburg Medex 3/4" MDF and glue together with ProSet+Cabosil mixed to a mayonnaise consistency and rolled on both sides. Then Vac-Bag. And I believe they run it through the oven once right before cutting in the router. One major challenge is the router dust is pretty flammable watch out for feeds speeds and dust collection.
Keep in mind, I’m not the expert on this, passing on what I learned when I looked into all this. I couldn’t find a router shop that was willing to cut the MDF, so for my project I made a male buck and laid up gelcoat+fiberglass mold halves with high temperature resin. I really wanted to use MDF though.
It’s funny that you guys discuss mdf molds right now. I’m just building my first one at the moment. I infused it before the final pass and it looks great for now! I’ll keep you updated. It’s amazing to see people working on the same ideas!
May I ask where you get your prepreg scraps from? I only built my foils with a wet layup which worked well and I never really thought about buying prepreg since it’s quite a pain to store and also expensive. But if you have access to scraps it’s becomes interesting!
Nice! Did you do that with a hand router? I assume that white thing is a depth & shape guide for the router? If so thats a really clever way of getting a 3D shape without CNC. Have you considered adding flash channels to stop resin getting into your closure bolts & locating pins.
Is that a stab? The mounting geometry or whatever is going on in the center is quite unusual?
I work in a startup that makes carbon bike frames so I’m lucky to have access to a whole bunch of equipment. Funnily enough we don’t have any wet layup stuff so my only option is prepreg. If you’re interested in trying look at (https://nexx-technologies.com/) they have a prepreg system that does not need to be frozen, massively lowers the barrier to entry, still pricey though.
Thanks, thats very helpful. I think I’m going to give MDF a try with a carbon mast, I’ll report back! Luckily I have access to a massive router with full extraction etc.
Jea a plug and composite mold would be the “propper” way to do it. I’ve done plenty of metal and composite tooling in the professional environment but its quite an interesting challenge trying to do things with limited budget and, to be honest, minimal effort.
It’s actually cnc cut. The 3d print is a sanding guide to protect the le and te. It works great and I would really recommend it. The foil is a stab I designed for a friend who uses it in his efoil. That’s the weird mounting geometry. In return I learn to make mdf molds and have access to a router in the future for unlimited prototyping! Thanks for the idea with the flash channels. I just closed the mold and started worrying about separating the halves.
Hi all, This is my first foil and dockstart combo.Everything is hand shaped from plywood with some hard wood stringers and then hand lay with fiberglass and carbon.I ve never tried foil before ,actually just had oportunity to see one RRD from my friend for the reference.It weighs about 10kg.I know i can make it a lot lighter now. Havent tested it yet. I still want to install scoter steering wheel (aka foilscott) i already put screews in the board for that. I figure its gona be easier to learn that way.Its an unusual path but i like the challenge:)
and have access to a router in the future for unlimited prototyping! Thanks for the idea with the flash channels. I just closed the mold and started worrying about separating the halves.
