MotorModders motor modding thread

ElectricGod

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I've been doing motor modding for a while.
I've never had a reason to create an account before.
I'll present all sorts of motor modding stuff.
Most of the things you will see here will be work I do for myself or others.
Quite a lot of the work done is for people all over the world.


Stuff I'll do:
Adding halls
Fixing weak areas of motors (bearings, shafts, soldering, whatever)
Rewinds
Tear downs of motors
Drastic motor rework (Example: Make a hub motor into an outrunner)
ETC!

No motor is sacred to me!
They all come apart and they all show their parts.
They all get stuff done to them to make them better.
Just becasue something is garbage from the factory doesn't mean it can't be made better.
I've been at this a bunch of years and done a lot of BLDC motor rework.
I know most motors can be improved a LOT!
I'll focus on outrunners and hubs for rewinds since they are pretty easy to do.
I'm not overly fond of inrunners and probably all you will see is me replace halls.
I'm not some motor guru, just somebody with practical experience.
There's plenty about motors I don't know or know only the basics.
Sometimes I care about motor theory and sometimes I don't.
What I do know is that every motor I've ever worked on was improved by my efforts.

If you have questions feel free to ask.
If you want me to measure something...ask.

My life is busy and I really don't have time for people that are dicks.
If ego and being a dick are your thing, just stow that crap.
If you are going to be critical of me or my work, just don't.
Again...I'm busy and I don't have time for your BS.
 
How big do phase wires need to be?? I mean, I’ve seen some pretty thin battery wires that handle 50A just fine without getting warm, but allegedly phase wires need to handle 20% more pulsed and therefore need to be huge. Why would they need to be any bigger than the winding they are feeding in to!!
 
This motor is getting rewound for someone in the UK. He burned it out trying to feed it 150 phase amps. Hmmm...no idea why that would let the magic smoke out! The guy has yet to pay me to do the rewind...so maybe it won't happen. He did send me his motor from Leicester UK and I'm in America.

She's wound for 80kv and wired delta from Alien Power. I'm going to rewind it for 80 kv and wired WYE. This will let me make less turns per tooth which makes more space for more copper on each tooth. I will be working to cram it full of copper. It's wound with 32 awg wire and the stator is only half filled...go figure! I'll be using 24 awg. It's pretty easy to get tight winds and not too horrible for copper to insulation ratio.

I've done a few rewinds...so here's a couple of predictions:
1. By weight of copper, I will double the amount on the stator and possibly 2.5X more.
2. Wired WYE and fewer turns will increase the copper cross section by at least 3X from the factory wind.
3. I don't have a working C80100 at 80kv to measure phase resistance. The best I can do is measure this ones phase resistances. I'm predicting that despite WYE, that phase resistance is still less than the factory delta wind.

No idea if/when the guy will pay me and I have other work for people that have already paid!
This might sit here a while...
 
electric_nz said:
How big do phase wires need to be?? I mean, I’ve seen some pretty thin battery wires that handle 50A just fine without getting warm, but allegedly phase wires need to handle 20% more pulsed and therefore need to be huge. Why would they need to be any bigger than the winding they are feeding in to!!

It sounds like you are thinking of the wires extending out of the motor vs the wires wound on the stator?

People that come to me want performance EV parts. They never ask me to tone down their stuff. They never ask me to make their stuff weaker. So let me make it simple. Less phase resistance is less waste heat. More copper cross section is also going to increase the current handling ability of the motor. Current is torque in a motor. More current is more torque. I am being deliberately overly simplistic, but you get the idea. Rewinding the C80100 for better than 3X copper cross section will get the phase resistance a LOT lower. It will also increase current handling a lot which means a lot more motor torque.

I've done some rework on hubs where the teflon wires going into the motor were 10 awg. Looking at the actual windings in the motor, they were more like 8 awg in copper cross section. The teflon wires were a LOT smaller than the windings and they were creating resistance. These hubs were getting over watted and the people that were using them wanted every drop of power they could get out of them. Phase wires that matched the windings was one of the things I changed. I had to make a new shaft for them so the wires could exit right at the side of the motor shell. I also opened up the sides so air flow could happen. Both hubs got triangular sections cut out of their side panels. I don't like all the goop people put inside of hub motors. They increase the turning resistance of the motor. They make a mess later if they leak out or the motor needs to be serviced. I'd rather have good air flow into the motor. Besides, being able to see inside the motor is kind of cool. It's sort of like scraping off the paint from inside your glass smart phone back cover so you can see the innards.
 
A local guy I know has an A2B bike. It's still working after all these years on all the original parts. Range is greatly reduced and of course it's a 500 watt hub motor so even glaciers accelerate faster than his bike. He asks me "What can you do to make it go fast?" Uhhhhhhhhhh.....everything?!!! So he in for the long haul and knows this will require a lot of work on his part. I told him to get a track hub for the back wheel and restring it without the hub motor. I told him to upgrade the rear shock and mechanical brakes to hydraulics. I told him to get rid of the shit factory tires and replace them with 16" moto tires and to go tubeless. He has a lot to work out! I've had an A2B hub apart before and they are nicely made except for the weak as a baby chick wind on them. 2 strands of 20 awg and 32 turns per tooth...UGG! We are going to rework it into an outrunner. This will be fun and he's in no rush. I've wanted to do this to a hub for a long time so we are going to give it a shot. I can mill parts so I'll be pulling the shaft and making a new one that locks to the magnet side or armature. The other side plate will get some kind of adapter added to it or more likely I'll make a new part that holds a shaft and skirt bearing and the stator and will be mountable. We'll turn his 500 watt hub into a pancake style outrunner and maybe get something like 8 or 9 kw out of it. I'm shooting for around 60kv to keep gearing it to the wheel in a single stage possible. It will be fun to rework the motor into an outrunner. While not overly practical since it will take a lot of rework, it's gonna be the best A2B motor there ever was!

After reworking the motor into an outrunner, mounting it like a mid-drive will be a piece of cake!
 
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