Thermal Images After Ride

Definitely. I would like to see the areas that are most prone to metal fatigue, so that I could make design changes to address the possible issues. Heating up and cooling down so often may affect the temper of the aluminum as well. Heat sinking the mounts and trucks may be something viable in the future. I’m strongly thinking that a redesign of the truck hanger itself is something that could change the game. ESK8 specific, so that motor mounts are easier to intstall and with less room for error as well as integrated cooling fins or mounting holes for a removable piece. Maybe even a hanger design that would fit standard truck bases. IDK, but I sure want to explore that area.

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Cost starts to become a big factor with machining costs but I think a cast option could work for the masses. There is a minor amount of fluting in our new motor mounts and it definitely drove up the time/cost over a basic mount design involving flat plates. Take a look at the pricing on precision trucks and you will see the big difference in cost over cast products.

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I totally agree with you. Cast would definitely be the most cost effective. I don’t think that it would have to be a fully CNC’d part to still be quite consistent and functional. If the bearing faces were milled flat, like Buck does on their trucks, and a machined mounting surface was cut for the motor mounts at a precise distance relative to the bearing faces, that would go a long way towards making them easier to install and a perfect fit for DIY and less skilled labor would be needed for production. IMO I guess the real question is: Is it worth it in the long run? Especially with $$$ setup and tooling costs. I’m curious…:thinking:

What about a hub motor design? I haven’t seen the schematics of them but I could imagine using thermal paste between the hub motor stator and the truck. You could also add some heat sinks on the trucks to pull heat away.

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That sure would help with what seems to be a common problem with hub motors. Let the heat transfer down the axle and off of some heat sinks. Totally doable!! :thumbsup:

I had never thought of this before! What is the main source of the heat? Is it the friction of the wheels moving on the ground, or the rotation the bearings? I’d guess it is mainly the motor mount transferring heat from the motor to the hangar.

@Jeff is there any chance you’d be willing to apply some thermal paste in between your motors and the mounts? It would be interesting to measure the heat transfer before and after.

@Ulfberht I love the idea of a truck design that is meant to help dissipate heat.

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I’m going to be doing an experiment pretty soon of heat transference with and without thermal paste applied to the motor screws, mount, etc.

Hope to find some good data. I will be making a thread for it.

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I think a water cooled motor mount would be more effective. Better to pull the heat as close to the source as possible.

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No doubt!! That would be just perfect! We are talking about considerably more cost and more parts to potentially fail, but I think it would be worth it! Especially for people that live in punishingly hot environments and like to run their board hard. It would be amazing if the battery and mounts could somehow be watercooled off of the same coolant lines. This sounds like a really fun concept to experiment with. Though it may be more expensive, I think people would be seriously interested in buying something like this. :sunglasses::thumbsup:

I’ll try and get a close up of the top truck (no motors) and the bottom truck (motors) to compare the heat. From that we should be able to determine what is contributing to the heat (most likely motors). Last I checked the heat from the motor mount and the truck is almost identical. I doubt adding thermal paste will make a significant difference in that case. Still worth exploring though.

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I have wrapped an 18650 pack with a cooling line and had good results on the bench but I think we are still in the air cooled days of this sport. Who knows what wonders await us when we start racing these machines on a closed course.

If you look around you will find some rc components available to plumb and cool motor mounts.

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Looks to me like the heat is definitely being generated from the motors. Truck is acting like a giant heat sink. Motor mount appears to actually be cooler than the truck (probably because it is thinner and can dissipate heat more quickly after the ride).

Here is a log of the ride. Total rider weight is ~235lbs.

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Great images! I got the FLIR One to do similar, but haven’t had a chance…

I’m wondering if the motors are actually heating through the mount to the truck, or more likely the bearings and friction in the wheel hub/gear and bearings are heating the truck - especially given 29mph! I would swap in some new bearings w/ fresh speed oil and compare to see if less heat or same?

Looks like I should send you a drivetrain for testing once they get back from fab. It will be interesting to see if the cooling fins make a difference.

Thanks!

Ambient temp today was about 28-30C. Based on the image from the front truck, there is some heating through the bearings/wheels but not much.

I doubt the wheel hub gear is transferring much heat since those bolts are insulated in plastic. I do regularly oil my bearings with Tri-flow. They are 3 years old and still spin forever.

I am always happy to torture test a drivetrain :slight_smile:

My battery/VESC setup allows me to pull 70 amps per motor with no stuttering.

What temps are u guys getting to?

A cooler motor is always better for better electrical efficiency, thewinding resistace does go up 40 percent between 20c and 120c, but that’s way hot

I’ve never heard of batteries needing cooling and have heard just the opposite and that people will warm them to make them perform better.

I’ve used thermal paste between hub motors and hanger. Black painted hangers. The hanger will abosrb a lot of heat but it wasn’t that productive as it seemed to stay in the hanger.

The e-go has a fan built into the rotor and that seems a great easy solution if u have the bolt holes on the back of the motor to add something. I’d think these were already available somewhere. I had a couple 3D printed

If u really want to conquer a mountain maybe bring a can of compressed air u can blast in.

The real solution is a bigger motor of course. For best efficiency a balance between iron losses and copper and with these small motors we have much more copper losses

For cooling, these little guys look pretty promising: http://www.micropumps.co.uk/

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