I didn’t bother to reinvent the wheel with props because there are so many tried and true designs already. What I did was used this very simple calculator Vicprop - Prop Calculator for planing hulls to figure out what diameter and pitch I needed for my fat ass to scoot along at 25mph given the kW I have available and the rpm of the system. Then I found and downloaded a mercury racing propeller design (which was far to big) and simply scaled it down with CAD to the correct OD, made some modifications like the square prop shaft and a few other things. That’s it. Printed it in PC-Max and bam!
This is awesome performance!Thanks for share!
But at 3500rmp on the prop,148mm dia and 200mm pitch with 26mph onboard this is no slip propeler ,is this even possible? .
Didn’t understand you with the duct… do you have duct with airfoil and without any angle?
guys maybe time to think in a complete different way? Put the propblade inside and the engine outside? Gives you incredible power and no sealing problems anymore…
@tunnelvision, I am very impressed that you got up to 26mph with that prop and with a duct. You said your CAD is available, you post a link to your prop and duct here? Thank you.
Is anyone building jet drive (impeller) if so what have you come up with thus far?
I have found that impellers 50-80mm like 16,000 RPM and 16,000 is also the sweet spot for many motors for electrical efficiency. Im looking for some impeller designs and nozzle with diffuser to 3D print and test.
Hi!
I used solas prop in the begining… I had 300kv motor with 4:1gearbox 12s lipo and around 3300rmp unloaded. Speed was around 12-13mph-foiling.For me at 75kg was enough but my 100kg friend couldn’t get on the foil… I got around 35A…
I build 80mm jet with fully molded carbon fibre impeller at the beginning ,but efficiency was too bad, I think it is very important (for classic jet) that the nozzle of the jet pushes water close to the air so the air can be soaked in to the steam(kinda mixture air-water). it seams weird but when water travel thru the air gets more kinetic energy- it can accelerate.Under the water there is no air after water leaving the nozzle so the acceleration is smaller…
I make classics jet-surf from it https://instagram.com/p/BUrB5G0jHfv/
For foil I think proper propeller would be the best…
…when foiling. I changed it becouse with the duct was like 20%less power, even couldn’t get on the foil . Then @Hiorth send me his design and it worked pretty well!! thank you Nikolai!
Then I designed my own 3bladed kort, with blade area close to the Nikolais prop. So now I can play with different pitch and blade shape…
It would be really nice if you could run it direct-drive,but can be to much load for the motor…
Sorry for the delay. Was busy with work and dealing with my boss.
I’m getting an error saying only pictures can be uploaded. As such you will find all the files needed from the motor back in the dropbox link provided. PLEASE NOTE all the files are designed to be printed on a Prusa i3MK2S in Polymaker PC-Max. I’m not sure what will happen if you print them in any other material or printer! Please pay attention to tolerances of your own printer**
,is this even possible? 
.
,but efficiency was too bad, I think it is very important (for classic jet) that the nozzle of the jet pushes water close to the air so the air can be soaked in to the steam(kinda mixture air-water). it seams weird but when water travel thru the air gets more kinetic energy- it can accelerate.Under the water there is no air after water leaving the nozzle so the acceleration is smaller…
. Then 
