Community designed/produced folding propellor?

[manif]

(Disclaimer- I’m a total noob with little knowledge on the electrical, hydrodynamic and propulsion systems that are needed for an e-foil build. As such I may misunderstand some stuff so feel free to correct me if I get things wrong. Im here to learn.)

Firstly, let me begin by saying there are many contributors here who have embraced the DIY ethos of this community with gusto and provided an excellent foundation of knowledge. Many thanks.

Where I’m at
Im starting my first e-foil build this winter (build log when I have something to show) and have been doing some research to find out what it entails. After a fair bit of reading its become clear that the propeller is a really important-some might say ‘pivotal’ part of an effective e-foil system. (Cough…. Sorry, couldn’t resist.)

So that’s what this threads about.

What I want
Long story short- I’ve decided I would like to have a well designed, durable folding propeller for my beginner board and wondered if any of you would be interested in one too?

If yes, read on!

My proposal
What I’m proposing with this thread is to combine the forums skills/knowledge base and real-world e-foiling experience with a bit of metal casting to produce a strong folding prop available to the community for less than 200euros each (rough back of an envelope calculation).

My end
As I’ve already alluded to in my Noob Status Disclaimer, I don’t have any of the expertise needed to make a good prop by myself…… but to quote Liam Neeson “what I do have are a particular set of skills”.

Gross exaggeration-what I really mean is I have a foundry and Im not afraid to use it!

Seriously though, in my day job Im consistently casting metals with thicknesses less than 1-2mm so I don’t think a prop blade will pose too much of a problem but we’ll see.

How I see this happening
We would need to:

1. set the parameters we want for our prop, eg motor type, speed, efficiency, battery etc. (decided by the community)
2. Someone to design and CAD a prototype (Is this YOU?)
3. Someone to make the prototype in metal (ME!)
4. Someone to bench and real-world test the prototype (Someone with logging capabilities-not me!)
5. Reiterate until we are happy with the results (general consensus?)
6. Produce a limited run for those who want one (me again or find a manufacturer able to do the required quantities at the right price point and quality)
7. Start again with different parameters for the next one if people are interested.
8. Have I missed anything?

(Note: I personally fancy a modular design with a generic hub and easily interchangeable blades for optimising speed, efficiency etc but this can be discussed later if anyone is interested).

What are your thoughts?
Is there a place for this ‘community designed/produced folding prop’ here or should I just take one of the existing 3D models kindly made available by forum members and just cast one for myself?

Final word for now
Id just like to be clear about one thing before I go - I’m not doing this as a business venture to cash in on the community. I will be doing this outside of my day job to give something back for this great forum. My hope is to produce something good for the members here, designed by us for a reasonable cost (hence the <200euros target price).

Let me know what to think.

Best, Mani

[Twstahle]

I love this idea. I have been working on making one for myself recently. Mine have just been 3D printed prototypes though. I have no prior experience designing propellers though. This was mostly for fun. I designed a two blade prop that I was able to get up on foil with and surf a wave or two after letting off the throttle. I have a 3 blade design in process. One of my early two blade designs can be seen here towards the end of the thread.

Complete Geared Motors

I have quite a bit of experience in CAD so I do not mind chipping in. I use mostly Solidworks. I would love to have community made design.

[manif]

Thanks for coming on board Twstahle and offering your CAD skills for the greater good! Much appreciated.
I had a look at your prototypes in the link and what you’ve done with your 2 blade prop is the kind of thing I had in mind when I thought of designing my own version. Great start!

I really like the shock absorbers idea to cushion and protect the system, definitely a must have in the ‘community design’. I might see about finding an off the shelf component so people can easily replace worn out ones without the need for special filaments and a 3D printer.

I was also looking at sail boat prop designs for inspiration and see some of them incorporate a helical gear mechanism to synchronise the movement of the blades.

It looks like a silentsync timing belt configuration.

I have a feeling these are probably patented but Im sure we as a smart community can figure out a similar system that doesn’t infringe .

I see you adapted your design (after a request from SoEFoil) to fit the 65161 motor. I suspect this is the most commonly used propulsion system on the forum so should be the first iteration of the ‘community prop’?
Anybody else have other preferences?

I think it would probably be a good idea to put together a basic overview of the casting system and materials I’ll be using to produce the props and give the designers some parameters to work with to optimise the casting process, pare off unnecessary weight and minimise post production ‘clean up’ (nobody likes sanding and polishing!)

I’ll crack on with this next

[SoEFoil]

From this link and the following posts, you have two folding prop designs from @superlefax and @leachim :

3D-printed folding propeller

Thanks to a good samaritan, and the power of CC, the models are back up on Thingiverse. Would be interesting to experiment around it!

[manif]

thanks for the great link @SoEFoil

[SoEFoil]

Look at this from @debeam got from a metal 3D printer, blades can be very thin.

Prop design share

To be honest I have not tested it yet. I think it will not hold up. Its ABS covered with epoxy. I should try anyway. I have shared the file with another person from the community recently. Maybe we will see some results there. I have concentrated on another prop which I am really happy with actually. Base design is also from this forum. I just made a stainless folding version of it with some minor mods. At least with my 65163 100kv setup this prop propelling me a little faster then with my FR pr…

[SoEFoil]

Or one like this

[ArminHarich]

I would add my aerodynamic experience from >20 Years Kitedesign, Paragliding, …
I ordered an foildrive and would like to optimize the prop.

That is a very efficient solution as slow gets smoothly joined again.
The 2 Props with opposite direction is good, but too much here I think.
The blades should be better if they are more like an airplane prop. But maybe i am wrong as that is quite rare.

Cheers, Armin from Flysurfer.com.

[cim96dm7]

Looks just as good in reality. Those props have diam 200mm for 50kW power transfer. Starting to think that our 152mm props might be a tad bit to o large for our 5kW drive systems…

[HelpWoody]

I am really looking forward to a video of this going in the water. Great work