Nice. What Jetdrive and motor are you using in this video?
It is a modified MHZ jet with 64mm. The motor is a Lehner TorQstar 7040.
It was one of the first runs with the new and improved setup in Corse. Was a really long way to get the whole setup stable.
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I more and more want to give the MHZ 64mm Jet a try.
But what Motor and KV for an e-foil? I want to use the Vesc 75/300.
How to atach a trustbaring and the shaft,
Könntest du mir helfen? 
For jet propulsion a high KV motor and for propellers a low KV motor.
Since I am still in the test and optimization phase myself, I cannot yet make any engine KV recommendations.
For a jet drive a thrust ball bearing is not really necessary. The pressure is created at the nozzle of the jet, at the moment the water leaves the nozzle.
However, to be on the safe side, I have installed a double angular contact ball bearing. This can take axial load well.
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The acutal motor is a 7040/6 so around 280-290 rpm/volt.
I am using LiPo cells in a 14S/1P configuration.
The can handle 300 A continiously (per cells).
15S was bad for the ESC…
If you need more, we can talk it Whatsapp
Some time has passed in which I have continued working on my project. In the meantime I have found the right O-rings and groove combination.
For the final assembly I am still missing two washers and nuts, unfortunately the DIY stores are closed due to corona.
Some parts I have printed again to simplify the maintenance. (easier assembly and disassembly)
I have built a water filter to prevent dirt from getting into the cooling jacket of the engine. In the video I have tested the filter with a syringe, it is tight. (With a 3d-printed sealing ring from TPE)
Some pictures:
the water filter has space under the cover:
I know the cables and hoses are very bad because of the drag:
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Nice job,
I’ll watch the progress with a lot of interest, and even more because we’re certainly close together (I’m on Geneva and you ?)
Good job
Today was good weather after a week of rain. Finally I could test my drive on the lake for the first time.
My conclusion is that it is worthwhile for me to invest further (e.g. waterproof electronic box, waterproof remote, mounting on the windsurf board, optimizing the impeller and nozzle)
With the standup board and drive in my hand I reached a speed of 8km/h, current consumption was about 60A with 6S Lipo. Throttle was at about 75%. More I could not give, since I could not hold the drive with one hand otherwise.
I also had the problem that I always created a vortex in the intake area which sucked in air and lost thrust.
My next test will be with my Windusrf board, which probably has better gliding characteristics than the StandUp board.
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Can someone help me make an extrusion? I am using fusion 360 and would like to extrude the sketch (image 1) along the second sketch (red arrow).
What do you want exactly ? I work in rhino and will try to make the extrusion. I just need the profiles…
Try loft feature.
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Thank you @Fruitygreen. Your Video helped me and i found the right function to do the extrusion.
@Tigerkiki: thanks for your offer. I could draw it myself by now.
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Very welcomed. Not my video but just passing the knowledge.
Built a 3D printed tool to prevent the O-rings to get “bites” from the holes.
Screws are M4, the tips are reduced to 3mm and fit into the holes in the tube. screw them into the holes in the tube before installing the end part with the seals. Add some silicone grease for lubrication.
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UPDATE:
Finished the mounting system on the windsurfboard and tested yesterday.
Reached more speed with the windsurfboard than with the SUP-Board.
Pulled 97A at 22V
How can i embed the videos?
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For this Speed is the current too much, many too much!
For this speed you need max 20 A.
Greetings Frank
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Update:
I printed a threaded nozzle outlet. So I can quickly try different diameters.
With the 35mm nozzle I have a good result. 102A (only 5A more compared to the 50mm nozzle) but more speed.
I have pulled the SUP from me and my girlfriend at the same time and reached about 10km/h. My girlfriend monitored the current during the test.
Probably tomorrow I can try the drive with the 35mm nozzle on my windsurfing board and make a video.
I am excited about the test tomorrow, but I think in winter I will build a small 500W auxiliary drive for the SUP and an efoil as well.
2 Likes
Go for the eFoil, it’s so much fun. The only problem in ch is the law.
I’m a jetboarder, and having a lot of more fun than the fly’ers here. They are having a lot of problems with the water plants.they look so pissed when I’m carving away from the beach 
Today I could test the 35mm nozzle on my windsurfing board.
The result was disappointing. Not faster than with the 50mm nozzle.
Video: https://youtu.be/jEmKtzIbxag
I let the surfboard go without a person for a short time, it goes just as slow as with one person. So it makes no difference. I would have expected the surfboard to go much faster without a person. What means that the speed of the water coming out of the nozzle is already much too slow?
Video: https://youtu.be/2aC6jalPQZ4
I have found that when I lift the nozzle out of the water the thrust is much stronger. It almost pulls me along. I would not have thought that the difference between the nozzle under water and above the water surface would be so big. But I can redesign it so that half of the nozzle looks out of the water.
Video: https://youtu.be/CZCtpkvJtGU