Radio control projects used to be made of materials such as metal or wood, and involve lots of hand crafted parts. That’s still one way to go about things, but 3D printing has become a popular tool in recent years. [RCLifeOn] has been working on a 3D printed jet boat, which recently got a serious power upgrade.
The boat in question received a 5000W brushless motor – significant power for a vehicle weighing less than 2kg. Powered by a 12S lithium pack, and outfitted with a water jacket for cooling, it drives the boat through an off-the-shelf turbine after initial attempts to DIY the drivetrain were unsuccessful.
The biggest problem in the project came from coupling the motor to the turbine. A 3D printed coupler was unable to hold up to the strain, while attempts to make a metal part failed due to the lack of a lathe. Eventually the solution was found by daisy chaining two off-the-shelf parts together.
The boat proved itself ably on the water, with the large motor proving more than capable of shifting the boat at a strong clip. It’s an excellent shakedown for the parts that will eventually find themselves in a powered surfboard build. We’ve seen [RCLifeOn]’s work before, too, like these stylish 3D printed sneakers. Video after the break.
I’ll just leave the jetsurf video here:
https://www.youtube.com/watch?v=eTAa9BDGYNw
but i might prefer the foil board design:
https://www.youtube.com/watch?v=3ah6FQP5ozk
Ive seen the surfboard one and the “pull behind the boat” model which looks a LOT like this one. Im suspecting someone showcased their vfx skills and erase the boat part of this video. the lack of detail of how the water intake is set up, if they’re keeping the motor in the submerged part of the foil how do they protect it, and where the “chemistry that really hates water” battery lives makes me wonder
– I was questioning the lack of wake a bit also, especially with the front shots showing where he’d been being so smooth. Seems the thrust required to generate that much lift from a foil would be creating more wake than that, but maybe not, especially if design goal was to avoid wake for the ‘serenity’ of it… $12k, crazy…
The foils are very efficient and cause very little wake. Once they are moving it takes very little energy to keep them moving. The motors are usually mounted just above the foil, so about 1 to 3 feet below the surface depending on how high above the water the board is gliding. The batteries are built into board and the rider uses a motor speed control like for an RC car.
[Missing Cognition]
I saw this as the Evolo that was a student project back in 2009 so it’s not magic, 10 years later and you can buy a similar thing over the counter for about $13000.
https://efoil.builders/t/the-history-of-weight-shift-controlled-electric-hydrofoils/742
Very entertaining
a brushless motor doesnt require much protection beyond correct material selection. The chemistry may hate water but if youve ever held a battery you are aware that one of the primary design considerations is not having the “CHEMISTRY” exposed. There are a number of well documented and proven hydrofoil boards that have been build over the years as well as powered surf boards….oh and as to your incredible concern for the omission of “detail of how the water intake is setup” ever seen a propeller? https://www.youtube.com/watch?v=XAMaQ09Skb0
Your “its photoshopped” editorial is better kept to 4chan and reddit.
If you don’t have a lathe, try the ‘Afghan Lathe’ hack to get those holes central! I used a drill press, which [RCLifeOn] had too. https://www.thingiverse.com/thing:7868
Now these eFoils start to show up in cash and carry markets such like the European sports retailer Decathlon:
https://forum.e-surfer.com/t/decathlon-efoil-from-takuma-good-or-bad/1928
Price is below 6.000 EUR. Decathlon is know for low prices. Not sure if this is a fit?