Making a folding propeller

EFOIL.builders Props & Ducts
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I would like to try to make a folding prop without having to use expensive CNC work and I thought about a solution but I don’t know if it could be strong enough.

  1. 3d modeling the most simple folding prop system as possible, something like this but of course with a different shape of propeller: RC Plane Folding Propeller 6 to 9 inch by CG-Manufaktur - Thingiverse

  2. 3d printing it, then using it to make 2 silicon molds using the silicons from https://www.smooth-on.com/

  3. Casting the final elements with a mix of epoxy and milled carbon fibre (like this one Materials, equipment and training for advanced composites with next-day shipping and expert technical advice. - Easy Composites)

BUT do you guys think that the final result could be strong enough? I’m ready to test it, but if it’s absolutely obvious that it won’t be solid enough, I won’t.

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The way I see it is how much is your time worth to you?
Would you prefer to spend the time on the manual work, or would you rather pay to have the parts cnc’d? You’ll probably find the cost would be similar.

In terms of the folding design, look more to marine props that are pushing than air props designed for pulling. The lift prop is a pretty solid design with a proven working mechanism for the purpose.

1 Like
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hi, i’ve been building propellers for flying from prepreg cfk and cfk, wet laminate for a couple of years now. everything as a hobby and with simple techniks learned by diy. the temper-box and vaccum system etc everything is built by myself. the forms are made of pure cfk mats and heat-resistant resin. All parts are manufactured in such a way that they withstand up to a 1000 kg tensile load with the lowest weight. It would not be a proplem for a foilboard to manufacture the propeller blades in prepreg. If someone wants to do so and the shapes can best be milled in aluminum cnc. I like to build the wings. Here is an example of my propeller. currently I have newer models, the videos including construction doku come the next few weeks in youtube. https://www.youtube.com/watch?v=Grxm8Us57Ws

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Thanks! I thought about molding as when I asked for a the price of a CNC made propeller for one piece in Switzerland the guys just told me to forget it. Maybe doing it with these chinese companies providing CNC work may be ok, have you already tried?

But do you think that the mix of epoxy + carbon fibre powder could be solid enough if I choose this solution? At least for the first tests?

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I got a quote from 3d Hubs which wasn’t outrageous. I just haven’t had time to do a folding design yet.

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I have a very good working propeller 3 plade running very eficient at about 2500rpm. Foiling with 900W. It as very straight blades. Do you think it would be possible remodel it as folding prop and then print with carbonPE, or peek? anyone who has experience of how strong this is?..

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That’s really awesome!

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do you have pictures of this prop?