Ebike guys had the same problem as us
Worth reading, with data on a bunch of approaches
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M Diy approach would be taking some generic heatsink , getting it red hot and wrapping it around a pipe. So two halves at a time. shave some fins off for mounting/gripping.
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I definitely have been. I have gearing for 45mph and my little maytech 6374s get hot as hell (80c) and then start acting funny (no mo towk) thatās why I bring it up. I needs to keep up with the local Onyx employees
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Good point. My initial test manufacturing method would require the two halves solution.
A single sleeve is much nicer for balancing.
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Thatās interesting. I think Iāll start my polishing up the interfaces on the mount//stator and making sure I get nice thermal flow.
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Aluminum quickly goes from solid to puddle. I donāt think it would be easy to heat it up enough to soften it for bending without it melting.
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THAT would be an interesting test to do!
Flat, absolutely parallel surfaces are the most important but after that the smoothness counts a lot. A very, very thin film of thermal paste can help if the surfaces are touching well.
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How true is it that itās the can vs stator that gets hot? @Battery_Mooch @RyEnd. Is this from experience or just what youāve heard?
The stator is where all the heat is generated. With mostly nothing but air (a poor conductor) gap between the rotor and stator, most of the heat is transferred through the shaft/motor-face/motor-plate.
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right right. I understand that part. Im just asking āwhats your sourceā Im not saying your wrong. Im just trying to really verify this info.
So, if you think about it, where would the heat from the rotor come from? Itās just spinning through the air on a bearing. Current is only flowing through the windings in the stator in order to generate the magnetic field to spin the rotor, some of that energy is lost as heat, produced from the windings themselves.
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So youre reasoning it? Ok totally fair. I tend to agree intuitively. I always like to know where my info is coming from is all! please dont take it personally.
It makes sense what youre saying. and Im no power engineer. But in Microwave (not for food, think 5g) engineering losses can occur in the dielectric (air in this case). Not to account for eddy current, hysterises losses, stray loss and what not. stray losses are literally parts of the EM not going to force, but directly heating the surrounding metal (think microwave, this time food kind)
Ill read a few sources and get back to you. Sorry to doubt you, please dont take it personally.
http://www.icrepq.com/PONENCIAS/4.320.ANDRADA.pdf
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Iām just simplifying. The vast majority of heat is generated in this way.
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6061 T0 with a thin motor interface less than 2mm would be easy enough to bend
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This exists for bike hubs already and turbulent airflow has been found to be more effective at heat dissipation than laminar. Iāve got a set of HubSinks Iām installing in my bike today, one of the big issues and one that can be solved in a sealed hub is the air gap by filling with a ferrofluid, in esk8 thatās not really possible, we donāt have motors completely sealed.
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stator gets HOTā¦ all my DDs Iāve added artic sliver thermal paste on the axle/stator interfaceā¦
I havenāt scienced itā¦ because of the awful thermal filtering on FW5.01, but they feel coolerā¦
like me
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Not mine, but saw recently (NZ)
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Their science is reasonable but that 18Ā°C difference is in the stator? Or the surface? Makes a big difference. 
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this is literally exactly what I was thinking.
but Ive had an idea. IM pretty conviced Stator is main heat source. @RyEnd <3 @kook
Now I want to try something like this:, but flatter (3mm) and with holes such that it fits between motor and mount
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That looks KooLā¦ but Iād rather have 6mm more motor diameter than 6mm of finsā¦
thatās just my way
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