Excellant! I would also like a set. Just curious. What top speed can I expect running 10s? I calculated 25 mph but Im not sure it is correct
Just click the PayPal link, Iām going to work out shipping for every once in ready to ship. 200lb will be fine, Iām 97kg there bigger a lot stronger bearings. Yes 25mph is correct.
Just paid 
Canāt wait!
Another video coming if the urathan factory will let me film.
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Howās shipping going @jacobbloy? Will we receive a confirmation email once youāve sent them? Also are there several colors we can choose from?
Did you get my update email? The color is hard, as material cost is high for the urethane, it costs about $15 per wheel to make and I have to mix up at least 10 wheels in each color and Iv got to make 30 wheels the die costs about $80 per color. But I will soon after every thing is shipped Iāll have more time and money to make some more and offer them at cost.
The pigment is a little dark as Iām trying to match the orangatang kegel, next sample batch Iām going to lighten it just a little.
Awesome! Also I just noticed I got the email. I was thinking black but any color works for me. Great work @jacobbloy. The overall quality is very impressive. I canāt wait to test them out!
So after a lot of time testing different urathan formula and adjusting the mould to are displacement.
The wheels are finished,
Also getting the motor winding right is the most important part and because Iām using a better quality stator we had to do a few different tests, but we have exactly 80kv.
All parts are finished just to be sent to me and assembled. See below a photo of the nice black caps and chromed motor can it really looks great.
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Awesome. The wheels look sweet!
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What size bearings are u using? Are they press or slide fit? Do they have a ācā rating for thermal expansion or has that not been a problem?
How long is the stator?
55mm long. Based on a modified 6355 BLDC motor but redesigned for low kv. The improved magnet quality, precision milling, and winding separates this from other parts.
Iām looking forward to benchmarking this. I doubt a dual (combined 30amp) is powerful enough for mountain boarding, but I might be pleasantly surprised. These motors should support up to 10s and (in theory) 40amps current. These have only ever been tested up to 12s with 30Amp combined.
Canāt be a 55mm stator the whole wheel is 56mm
What is the magnet quality?
What does benchmarking mean? Riding I guess.
Like I said, this is based off the 6355. It has a diameter of 63mm and a stator length if 55mm. Additionally the thane sets a final diameter just over 80mm.
N48 (non SH in this group) so around 1.5 Teslas ideally.
Benchmarking as in taking measurements for comparison. Iām an engineering student and Iām currently working a a solid stator (made of compressed ferrous material). Ideally itāll be more effective than electrical steel.
Should have waited until the morning to respond - Thanks Jacobbloy.
O ok I thought these fit in a kegel wheel. The kegel is 56mm wide.
Making a stator. Cool. I was into the idea of making a powder core once. From what I read you can get a better result as you arenāt limited by the shaping of laminations and can therefore use the endturns
My university has developed methods for powder iron compress statarās and have a patent on them, but they arnt aloud to work with me on them as they have contracts and non disclosure agreements with clients.
Got it a Google (Adelaide university) itās interesting.
The stator is 5130 so 51mm diameter and 30mm long the same as is in the rspec motor.
My total motor measurements are 56mm wide from cap to cap, the diameter is actually about 68mm because of my thicker magnets and the wheel groves. My wheels are 56mm wide 83-85mm diameter (because of urethane shrinkage)
At the moment there is a lot of work going on with hub motor and itās great. There is myself Carvon Hummina NVG And companies like mellow and inboard but I like the community supported motors better like carvon and hummina and NVG because it incurages improvements.
Itās a tough challenge and I wonder how long any of these hub motors will last. I feel like they are all underbuilt. having an aluminum shaft to start is not ideal. Since there are such extreme forces the bearing must have no movement in the housing and on the shaft. Ideally the bearings then should be press fitted. In my searching manufacturers wonāt give interference fit numbers (press or shrink fit) for the thin bearings that are typically used in these smaller motors. While they do recommend an interference fit due to the extreme loads they canāt give a number (such as one thousandths of an inch interference or overlap) and say experiments must be done as the expansion of the shaft could possibly snap the race on such thin bearings. So a tight slide fit with retaining fluid is safer and seems to hold well anyway.
the thermal expansion especially of the aluminum shaft which expands double steels expansion rate and you donāt have to get near the bearing max temp of 250f before both bearing seats expand and put a lot of pressure on the bearing races. They will start to squeeze creating greater friction within the bearing shortening its life and at worst even binding it. Bearings need to have both a radial and axial clearance inside the bearing for the thermally expanding motor and the ensuing squeeze. A āc3ā or even āc4ā bearing is intended for just such a high heat situation and has the bit more radial and axial play in the bearing thatās needed to allow the balls room when the squeeze happens. The airgap needs to be a fraction bigger with these but I forget the numbers and itās minute. The electrical aspect of the motor is easy really and you just tell the manufacturer what magnets and winding and kv you want. Itās all available and getting the torque needed isnāt a problem. But if the motor starts to rubā¦the plating on the magnets is something like a thousand of an inch and it goes quicklyā¦then the fragile interior of the magnets deterioratesā¦and then if your lucky they donāt turn to tiny chunks of head over heals stuff. Sealed bearing are also more appropriate than shielded for the rough environment
i get all of my parts machined to 0.01+/- or 0.001 for high parts that need high tolerance like the motor can where the magnets are glued, as i get an air gap of 0.5mm constant and this is why i use arc magnets not flat because there is less inconsistency in the airbag.
magnets are made in a mould and have a tolerance of 0.1mm so my high tolerance on this part helps with this. the problem is you canāt just ask your motor factory to make what you want they all will ask for samples, i have source my own magnet factory because the magnets that most of these factories use are cheap and i pay for the premium $0.20 compared to the $1 i pay per magnet.
my bearings are not cheap and are made for so much more rpm and torque then these motors are producing. u have the magnets press fit to the shaft but not to the caps but they still ant easy to get out.
the shaft is alloy, but please remember that there is also a steel shaft inside of the alloy shaft, the same shaft that is used for all longboard with racers going down hill at 80-100km/h and the slid braking where down hill force is grater then my motors that you can have a stronger shaft them what they use because it is reinforced by the alloy shaft.
i have been making hub motors for over 2 years and made a lot of these mistakes that you have made clear, but have learned from them.
but your welcome to participate and please share your own opinions and any ways we can improve i will get my exact bearing product code but it is a HCH 17x30x7mm bearing, i would rather use a 17x40x7mm bearing.
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What is premium about your magnets? I find you can get good magnets with .1mm tolerances standard on the web in all kinds of temperature abilities, strength, and platings
Bearings are rated for rpm and for static and dynamic load. The torque from your motor is not related to what the bearing will experience
the danger to the aluminum shaft is it will be deformed if the loads go through a bearing that isnāt permanently fixed on an aluminum seat regardless of whatās under it.
Checking out Staryās recent update. We should definitely look into the planetary gear setup.
Jacob - Have you tested your motors on 20% grade hills.
As of now, I donāt think they can keep up w/ the belt driven as far as hill climbing goesā¦ It would be a great to get rid of the belt drive in the near future completely even for hill climbers.
I still need to setup Carvonās (Jerryās) setup and test it up in the hills around here but Iām afraid of having it fail and me walking it up LOL.