Running inrunner in water?


#1

this is the stupid question of the day , the answers is probably : no , but

i used my efoil about 4h this week and when i took apart my pod, it was feel of water (because i had no o-ring, no cables glads…) i am using a 40mm motor in a 50mm tube with a 47mm gearbox, there is not much space to put good o-rings…

since it has been running in water almost since the beginning and that i did not have any problems at all and i will take it apart often (even if i put o-rings), and new sls parts will cost me 2 motors

do you think that i can just leave it like that, flush it after every ride and buy one motor/year as a servicing part?


#2

I dont think it is stupid at all. Basically, we could incorporate o rings on the shaft inside the motor/gearbox if at least some space is available, waterproof exits of cables from the motor and thats it. problems would be corrosion on motor/gearbox cases, not sure which materials are they. its much simpler to put everything in tube and just waterproof tube exits and much more flexible designing mast mounts and simmilar. which imo needs flushing from salt anyway. Almost same thing are members doing with outrunners with direct cooling, i thnik they only change bearings and waterproof windings.


#3

Originally on our first couple prototypes we had water in our units also and inrunners ran fine. I’m in Fresh water so that will help things last but I don’t think its idea, and salt water will do some damage fairly quickly.

But with that said I cannot believe how well “Corrosion X” works. I sprayed a motor inside and out, and a thrust bearing and they run perfect and zero corrosion weeks later, VS no "corrosion x) on the previous thrust bearings and they rusted solid in 10 days!!! so get it if you don’t already use it, I also spray all my electronics as its a protective water proofing solution as well, as lube, and penetrating oil.


#4

I was also thinking the other day, what id we just packed our motor tubes full of electrical gel, this way its full of non conductive gel, and it would really dissipate the heat from the motor well. Just a thought?


#5

@VeFoil What version of Corrosion X do you use? I see there is a few different ones.


#6

i have already waterproof the cables and connectors, i was suprised i didn’t have any troubles with that,
waterproofing the motor shaft , bearing is impossible, and i an more concerne with the water that stay between the windings, very hard to clean:

this one is good?


Propulsion System - Motors, Gears, etc
#7

I use red can Gregory.


#8

I can tell you that using o-rings in an application like this would be quite hard.

I have made many washing machines for some industries and the solution I had used was simply a spring with some pressure with a support from inside and custom-made poly-amid with a hole with the dimension of the shaft.

After you’ve done this. If you obey the tolerances for the sealing you made with polyamid. It’s gonna go just fine.

Before this one, I had tried very expensive seals in many different sizes. It’s all about the pressure you apply on the shaft, if you have too much it is not going to turn efficiently. Even if you get the best o-ring in the market, It is not going to be adjustable.