There is a ton to learn about propellers for your DIY electric hydrofoil board. There are endless parameters that can be tweaked to make a prop work with just about any propulsion system.
I have spent a considerable amount of time working on propeller specifications to test to have the best possible custom diy electric hydrofoil propeller.
figuring out the number your pitch, diameter, rake, cupping (if any), directional rotation, and the number of blades each has a drastically different characteristic change for the boat and your DIY Electric Hydrofoil.
For example, a smaller diameter prop should be used if the prop is lower in the water. A high rake prop will work better in aerated waters. Also, higher raked props will push the nose of the boat/electric hydrofoil board higher out of the water. In fact, when watching PacificMeisters video with his high raked prop you can see how his diy electric hydrofoil board is angled upwards to the sky when riding, VS a lower rake which would provide a flatter surf like ride.
The number of blades that should be used will vary on your setup, size and feel you are trying to achieve. I will be testing 3 blade and 4 blade props I had made for my electric hydrofoil board and I will be showing you my propellers in the build videos starting this week. Bottom line, more blades means drag is increased. However, the ability to grab more water to load the prop means the propeller will “feel” smoother.
DIY Electric Hydrofoil Propellers
There are a few ways to go about getting your DIY electric hydrofoil propeller. You could simply download some of these free 3D propellers and try them out. Keep in mind, 3D printed propellers will require lots of sanding, smoothing, and sharpening the edges, and they will likely be very thick, which will dramatically reduce the efficiency as well. Also, there is a good chance it will break from flexing, sun, and other elements.
I have gone the route to get custom props designed for high speed, all the elements, and is specifically for being used in a duct (ducted propeller). Here you can see my larger 3 blade and the smaller 4 bladed for my diy electric hydrofoil board.