If you take into account the reduction in area when designing there is no problem, you have to have enough material so the iron won’t saturate too much, but taking a existing motor and doing that could be bad, and keep in mind that the exact location you put them you have the coils going over the teeth
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Ah ofcourse, the coils wrapping around. But yeah I suppose I’m imagining it being taken into account in the design process, and not being added afterwards
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The problem with running anything through the motor is… you’ll need to use a bigger motor. I don’t see how there’s any space for anything. Unless you have a tiny straw but even then I doubt it would cool anything?
If you go any bigger for motor size… you’re almost getting into pneumatic wheel sizes.
In that case, might as well go bigger motors and have a direct drive specifically for an 8" Tire. I think you’d have a ton more surface area for cooling.
So first thing is to test the following see if we need to change anything else.
- Bigger Rear Truck with more surface area
- Then test again by adding Statorade.
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Thank you.
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You should give a try to ferrofluid even on satellite motors, but they have to be sealed on both sides like the maytech ones, you may even have to seal them better with retaining fluid, for science
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So tonight while I had my enclosure opened to work on my receiver, I decided to rotate my wheels, clean my TBDD hangars/motors, and saturate the space between the hangar/motors with thermal paste.
I’ve noticed a couple benefits so far besides what seem like lower temps (don’t have my full power board built back up just yet and it was cooler out tonight)
First, the paste eliminates the motor chatter completely. That small space on the square part of the hangar, the motor rotates around that just enough to clack sometimes when braking, accelerating, or from bits of cogging at 0 speed. With the paste in there, that’s gone and they are always 100% smooth.
Secondly, and probably more importantly to this topic, the motor cans are noticeably cooler than the hangar/cooling fins now. Before, they were about the same temperature when heating up (cans might have actually felt hotter than the hangar itself), but now the fins are definitely doing more heat-sinking than the cans themselves. The motor temp drops a lot quicker now too.
I really can’t wait to try statorade in these motors now to see how combined thermal paste between motors/hangars + statorade works to keep these things cool. I also can’t wait to pull 160 battery amps through these again to really torture the crap out of them and see how these cooling solutions do under extreme load.
The only downside I can see is the mess. It’s messy.
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What thermal paste did you use and where all did you put it? Just on that little square piece where the motor locks on and spins around? Did you just do a layer around the whole square or what? @Skatardude10…? My TB DD’s are already out of comish cause magnets came loose in one of the motors I’m assuming due to how hot they get EVERY single time I’ve tried to use them no matter If i have high/low settings or am riding on flat/hills Im always losing power or it’s being drawnback cause they’re too hot. So annoying. I haven’t even pushed it to ride like I normally do yet either. Waiting to hear from Dex on what he wants me to do to get the bad motor swapped out.
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I used insignia, 5G tube from Best buy, $7.
I took the motors off and did the whole cylindrical portion the motors slide into. I flipped a lot all around right by the axles, and a bit less all the way down the round portions stopping at the square parts. When you slide the motors on, they won’t slide all the way into the square parts. You need to squeeze them all the way into the square parts and the paste will come oozing out the square parts when you push the motors on. Presumably this means paste is getting squished into every air gap in there.
I went ham with the paste with about half my 5G tube. Any excess will squeeze itself out when you push the motors on.
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have you considered 4WD with half the amp limit per motor? for the same acceleration each motor produces 1/4th the heating via I^2R=W
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Yeah for sure. I’ve considered it, I just can’t pull that kind of additional purchase with my other half 
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Are you willing to use smaller diameter wheels or rewind for lower kv? For the same acceleration you can get less heating but you’ll sacrifice some top speed…
Nah, if anything i’d rewind for higher top speed and cope with more heat.
The heat, without any thermal paste/statorade/extra fins is still manageable even with crazy battery amps. At 40A per motor, the heat is negligible, it’s only at 80A per motor that I need to be mindful, allowing for some cooling time between charging hard. My goal is to eliminate the need to wait for the motors to cool when pulling 80 battery amps per motor… I think it’s do-able.
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The motor heat comes from the motor amps… if you limit to 80a motor amps and 80a battery per motor instead of 160a motor 80a battery per motor, you’ll still have the same acceleration when close to your top speed but half the acceleration from a stop sign but 1/4 the heating up till very roughly half your top speed then the heating starts to equalize with both options at higher speeds. but basically you can sacrifice some low end acceleration without giving up the high end, and lessen the heating at the low end.
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Ah, I am not running 160A per motor… just 160A combined, so 80A per motor.
Perhaps write a thoughtfully worded letter to a motor builder asking for beefier direct drive windings and stators… ? twice the copper means half the heating for the same acceleration. eliminate the heating at the source. 
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how did you remove the TBDD from the hanger? mine appear to be quite tightly affixed to one another.
I’ve seen some Thermoelectric Coolers in the past few years flow through work. True, they would need to be powered by the battery system somehow. I’m not positive on where it could be mounted, but maybe an option can come up sometime.
cool thanks for the quick reply
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I got a bottle of statorade on the way, I’ll let you guys know how it goes. As it is, thermal paste between the hangar and motors are working really well to dissipate quite a bit of heat to the hangar, with not so much to the cans… but over time the heat still rises to top out at the 85°C cutoff eventually, just not nearly as fast. I’d like to eliminate hitting the limit no matter how many amps, and if 30-40% better cooling is possible that would be super nice!
By the numbers, the statorade should be effective up to about 20 mph, which is perfect for cruising between spurts of speed.
Now my question is, has anyone here taken apart their TB DDs to get to the magnets yet? any advice for the best way to go about it? I hear the big bearing is really tough to remove.
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