I have another thought. Wondering what you think. I assume you know of the APS-70110, Water proof 70mm outrunner Alien motor that is in a Stainless Steel can. That motor seems very similar to the motor Jsonnett is building. MaxMaker and some others are using this new motor. It might be the same motor in a different can. Would you expect to see the same problem with that motor?
Hi PowerGlider,
Do you have a model of your prop? Iām looking at the 80100 motor(130kV or 80kv/7000W) or the motor you are using. The 80100 may be overkill. I donāt think I need that much power. Wondering what you prop pitch is? I donāt think you are foiling but its probably enough power to get lifted.
thanks
Mike
I can confirm, 80100 is overkill.
but after doing a full complex build for month and ending up under power, overkill is a nice optionā¦ at least it works, i just started a thread showing how i used it.
I have the 80 KV version. I use a Solas 0001-073-06P so pitch is 6 inch, and it seems appropriate. Top speed might be a bit high, but that might be just because iām starting, and who doesnāt like a bit extra speed ?? 
3 Likes
that sounds good Mat and I agreeā¦Iād rather have too much power. 
Do you know how much torque that motor has? The power glider motor has 6.9nM which
I think is enough. Ok, look forward to seeing your posts on your set up. Iām getting close to ordering partsā¦and then Iāll share.
No idea about the torqueā¦ all i know is that it worksā¦ and the motor doesnāt seems to struggle too much to rotate the prop. All i can say for sure is that it doesnāt stall.
I installed a power meter to get more data when riding, but thatās a big failure as i canāt read it when riding and it doesnāt record the dataā¦
My build is in the thread ā80100 direct coolingā
Pop a gopro on and aim it at the meter
3 Likes
Sorry, i do not have any model or STL files of the props i am using. All of them are commercially.
First model was 7 1/4 x 5", cut back to around 170mm in the old duct
2nd was the same but cut back to 137mm in new duct
3rd is 7 1/2 x 8" cut back to 137mm. I also plan to test 7 1/2 x 7" and also cut it.
All have pinion drive, the later ones i also cut the hub to adapt to the motor to make it shorter. The better quality was the Yamaha branded.
Have a look here:
You can also try the plastic Solas ones, like Mat, i did not use them but thought about.
ok thanks. I will get a few to test. What dia are you getting the most thrust out of? and which the most speed? Is the yamaha the best performing?
im using 2x 83100 watercooled outrunersā¦ and you say your single is overkill haha
they are rated for the same power as the 80100 so i think you have the right numberā¦ if youāre building a family foil
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Maybe interesting:
http://transistor-man.com/submersible_thruster.html
he uses the same motor, but submersed in oil.
According to his tests he gets about 120lbs of static thrust @12S 3,5kW
http://transistor-man.com/submersible_thruster_testing.html
The design is a bit bulky (imho), but I guess the glass tube saves much hassle of isolating or epoxying the motor.
Also he has a nice prop design, optimized for 2k RPM no ductā¦
The CAD files are attached for solid works.
Also there is a 3D-PDF to get an impression (if you donāt have access to solid works).
3 Likes
wow, thanks for sharing Giga. This is right where I amā¦
I have an encapsulant coming for motor but also looking at
oil filing a small tube which could also be pumped to cool the
esc. Either way should work but want to keep it simple.
Finally, I have made quite a bit of progress since my last post. My foil is working OK. Sometimes it even still works at the end of my test ride. I am able to foil on my knees for almost a minute before falling off.
It is now ready for testingā¦
The big question is whether there will be enough heat dissipation through housingā¦
8 Likes
Today I manged to get to a standing position on the foil. I went for at least a minute.Most of that minute was slower than on foil speed. I am running a dry pod 83100 out runner, actually I have 10 ml of mineral oil in it. I have had no problems with motor heat.
I believe I do have a problem with my ESC getting to warm. When I fall after running hard for a few minutes. My safety lanyard kills the power to the ESC. The ESC will not restart until a couple minutes pass.
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Nice setup! How have you secured the battery box to the board?
The battery box, has 4 nylon 1/4-20, 3/4" long bolts passing through it. I have automobile gasket sealer on the heads of those nylon bolts. Those nylon bolts screw in to steel 1/4"-20 coupling nuts on the out side of the box. The coupling nuts recess in to the urethane foam surfboard. Then I screwed steel all-thread into the coupling nuts with big washers and nuts. Its a little ugly but it has never given me any problems.
Here is my battery box. On my second day learning to ride it after about 30 mins I got into some weeds. I turned the board upside down to clean the weeds off the propeller. At that point one of my low voltage battery alarms started going off. So I slowly powered back to shore. When I got to shore the other battery alarm was going off. Turns out I had about a cup of water in the box, when I turned the board over the water got everywhere. Fortunately after sitting in the sun all day and shot with a leaf blower everything started working again.
Now I have added a way to add some air pressure inside the box before I leave. You can tell right away if you have a leak.
I am really curios how things work out with your motor selection. When I first heard about that motor I thought that looks a like the size of the motor Lift was using for their E-foil. I recall thinking that If you drove it with 14S ( thats what I heard Lift uses) it would put out 6500 watts ( thats what I heard Lift uses).
In a effort to get my ESC to run a little cooler I changed from a 6" pitch prop to a 5". When I went out to test it, the board was behaving strange. Vibration, did not want to lift off even at faster speed, sluggish. Within about 30 seconds the motor cut out, I was on my knees and was thrown over the nose of the board, jammed 2 of my fingers into the front of the board. Long story short, I had picked up a bunch of weeds on my prop and foil. That destroyed my 200 amp Flier ESC.
