Mellowboards - hub motor

I met Mellow guys yesterday. Great fun and good vibes !

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Has anyone seen a better exploded view of these motors? I wonder what materials they are using in the motor. Aluminum or steel? pressed or just slide fitted together? the difference between a lightweight aluminum which necessitates a slide fitting and a strong steel and press fittings decides how long these will last. Maybe aluminum with a steel sleave. From the looks of it the hanger is aluminum and also the bearing seat for me big bearing. It's a big bearing and a big surface so maybe fine. The outer smaller bearing sits on a steel shaft but what's the bearing housing made of?

How does the enclosure stay put if it's not bolted to the board? Just the mounting point under the baseplate?
 
Hummina Shadeeba said:
Has anyone seen a better exploded view of these motors? I wonder what materials they are using in the motor. Aluminum or steel? pressed or just slide fitted together? the difference between a lightweight aluminum which necessitates a slide fitting and a strong steel and press fittings decides how long these will last. Maybe aluminum with a steel sleave. From the looks of it the hanger is aluminum and also the bearing seat for me big bearing. It's a big bearing and a big surface so maybe fine. The outer smaller bearing sits on a steel shaft but what's the bearing housing made of?

How does the enclosure stay put if it's not bolted to the board? Just the mounting point under the baseplate?
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Just the 4 bolts through the truck base plate. There was previously an additional attachment at the extremity of the battery compartment, but it was discarded in order to be compatible with more decks, since it could potentially damaged a flexy deck. There will be something in place to absorb shock and noise.

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http://www.mellowboards-shop.com/
$1300 euro.
$1600 euro with the board!
too rich for my blood. :(
 
Awesome looking stator. What size is it and more so what the hell is it made of? Looks like glass. And the center is really weird. what are those metal bead-looking things are for. The stator seals the wire in. Very different and strangely doesn't look anything like steel...which I can't imagine it being anything else as it needs to be steel. Maybe it's not really the stator they use but a mock-up.

Still can't tell for sure what the bearings are sitting on. I can see they are using a solid bell for the rotor and I hope it's steel. That would make both bearing housings steel. The overall design is the same as what I'm selling. It still looks like the hanger is aluminum. Maybe they add a steel sleeve to it then the big bearing.
How is the rubber held on? And how is the motor's torque transfered to it? It has no grooves

If it's too rich for you I'm selling pairs of similar motors for a lot less.
 
By using grooves, don't you "lose" space that your could have use to make your motor larger? (since increasing diameter is exponentially better than width) From their photos, it appears the PU is bonded to a plastic core. The grooves are radial on the exterior of the hub.

Hummie, do your PU wheels have a plastic core or is it pure PU? Stary's design is very strange: a tight-fitting (except with water or dust ingress!) sleeve over the smooth rotor can. A ring prevents it from lateral motion, but torque transfer is done by pure friction of the PU surface against metal.

They've said the drive enclosure is magnesium (alloy?) but I'm not sure if the hanger is too.

I like the extra PU added around the sides to disguise the wheels.

Hummie, I like the addition of screens to your model. How are Mellow and those Chinese factories able to seal their hub motors and avoid overheating?

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You can see the grooves as a bit of space lost that could've been motor but I like them since it's only 2mm and they enable the rubber enough purchase so no core is needed. It is a thick 1020 steel bell that redirects much more flux back into the motor. On a typical outrunner made to be light much of the flux escapes and you can tell by how easy it is to attach ferrous material such as a paperclip to the outside. Not the case with this thick steel and also, more importantly, it's really strong and I've had motors run over by a car and an suv without a problem ( the magnets are positioned behind each of the 14 groove as surprisingly the magnetic field doesn't come from there but comes out the sides )

So they are transferring the motor torque to the rubber through a harder core and using those side grooves. Cool design but I like mine better as the grooves on what I have allow enough purchase and don't need a core.

I'm curious how it will deal with heat as well being sealed. I've been designing a cap that can go on the outside for forced air cooling.

That pic of the stator must be a mock-up in plastic or something. How the teeth seal in the windings is nice and would add more valuable stator tooth for flux holding ability. But what's inside is unknown and all I can find other than that plastic stator are 3D imagines of a more typically shaped stator
 
That's sounds really slick the way you use the motor can to push PU and hold the magnets at the same time. How do you adhere the magnets to the rotor can?

I get the feeling that Mellow is aware of the competition breathing down their neck, and they don't want to show so much now so that the German special sauce will come more as a surprise later on. From the one or two updates I've seen, they are very heavy into modeling and testing, and are as concerned as you seem to be to get the most out of that flux.

The next time they come to let me demo, I wonder if I could "accidentally" get it run over by a car to see how durable it is. ;)

About that forced air cooling...intake in a hub is obligingly close to the ground, dirt, etc. Is that good? Couldn't ferrous dust build up after a while if you force it in?

Why is your stator/rotor only 25mm wide, whereas the can length is nearly twice that at 49mm?
 
The magnets are glued inside the rotor as normally done. I meant that behind each of the 14 magnets is where the groove is

Yea air intake will likey dredge up some stuff. I doubt I will use the air scoops often but want to see how well they do and if I can cool two motors down enough to go up mount Tamaulipas at full speed.

The stators in the motor are small so as to get the whole motor recessed in the wheel. Could've used a longer stator and had it stuck out the side but didn't want to.

With the all steel version I'm selling all the best components possible are still in there but will have an airgap less than .4mm since it's all pressed steel and the tolerances can be really well controlled.
I'm no competition for these guys. Diy vs compete stuff is largely a different market. One day maybe with some promotion I might sell something but at this point I don't have even a business card or a website up. It would seem I'm making these motors for me!
 
Although I wasn't referring to you, I actually think that you and Mellow actually are more similar than you think. You are not just assembling, you are creating: making motors from the ground up for a specific purpose...and a specific performance, despite the cost.

Also, I'm probably old-fashioned, but I love your cans (I hope you're a guy, because if I said that to a lady....) since I'm totally for anything that keeps an e-skate looking and feeling like a traditional one. For some reason, the tech seems so much more impressive when it's all hidden.
 
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