How does it handle temps(thermal conductivity value(k))? Or rather, what is the melting point? Do you have any FEM simulations or tests to support your claims? I demand technical data! 
this is a damn great idea! i would definetely be interested in a sleeve for the Carvon torquedrive!
This sounds greatā¦ if you have any desire to make it I would love to be a product tester 
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Melt point is around 400F - 204C. If you have equipment to measure TCV I can send you some samples so put a sock in your demands mister 
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so thatās a no for raptor hubs? 
Whatās TCV? Pu is normally a thermal insulator but your saying you have come up with a version with conductivity almost on par with aluminum and half the weight. Iāve looked and found papers where doped with carbon Pu has shown better strength, which is surprising, but how do u get almost as thermally conductive as alum? How do u know?
Iāll try it! Or test it. Whatās the tensile strength after doping?
Good morning, here was my test setup.
1.5" thick samples placed on a hotplate and the temp differential between the surface closest to the heat source compared to the surface furthest away from the heat source after 30 seconds and one minute then averaged. As an example, if the heat source side was 200 and the side furthest away was 100, I call that 100/200 = .50 expressed as a percentage is 50%
Data:
Aluminum block: 69%
Untreated Urethane: 29%
5% load Urethane: 39%
10% load Urethane: 57%
10% load / Aluminum is 57/69 = .83 expressed as a %, the 10% loaded material is 83% as efficient in transferring contact heat as Aluminum at 1/2 the mass.
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Going by your results unfilled pu is 42% as efficient at transferring heat as aluminum. That canāt be right. That would make the Pu more thermally conductive than most metals. https://www.google.com/amp/s/www.engineeringtoolbox.com/amp/thermal-conductivity-d_429.html
Alum is super conductive and regular Pu is a super insulator. Finding even a highly filled resin for thermal transfer, like stycast epoxy or thereās some conductive silicones but data sheets show they are maybe 1/30th as conductive as alum and they costs a fortune.
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I wonder how urethane cures in my oven if it is a super insulator. The only polyurethane I see listed there is : Polyurethane foam 0.03
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Weird hard to find solid Pu numbers.
Do you have a picture of your setup Brad? I think Hummie is right as there is something going on with the experimental setup
By what you said the main culprit would be radiation and convection heating up the top of the samples, so you arenāt measuring the conductivity alone, but the sum of the three mechanisms of heat transfer
The got the same result that I did with the control so perhaps my numbers are good:
Sorry, no pictures. A hot plate if fairly easy to imagine though.
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I think same unit of measure.
As with anything, proof is in real world applications so if you have one in mind put it out there. If my numbers are right or close, the additive may counteract other desirable characteristics of the base material rendering it useless for the application so all we can do is give it a go.
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Haha. I feel on the forum weāre in the age of search and not do. U make it happen and I want it. But Iāll take any resin or solid stuff u will send. For anything. Iām curious about how ur Pu performs. I think with the powered boards all putting leverage on the pivot cup n bushings they get eaten up. And I canāt stop mine from squeaking! Tried soap chips liquid soap. Oil. All kinds of oil.
I got some thermally conductive silicone to make phase wires and was bummed how weak it was and wasnāt doable safely. But with the adding of carbon fill itās encouraging that instead of weakening it strengthens. Seems anything will be possible.
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One way to make it way more effective is to use ferrofluid in the airgap of the motors
The same Justin from ebikes.ca do using their Statorade and Hubsinks, ferrofluid in the airgap and heatsinks on the outside of the motors
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Have you tried our internally lubricated WFB 96a pivots?
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Iāve tried nothing and only swapped out standard Paris stuff for some of a bunch of unknown harder yellow ones I got from skates on haight for free. You know the lady who works there? But one day with all my thinking about it Iāll have to do some blind testing. Maybe three turns of the wrench for all and the variables are gone
But how can I get rid of these squeaks now?