Re-winding a hubmotor

[Farfle]

Mmk, started winding today, ended up doing 4 paralelled strands wound two turns in wye for a rpm/v of 11.2 right inbetween a 5304, and a 5303, it should do about 60 mph at 100v. It takes about 20 minutes per tooth right now, sooo, assuming I can get it down to 15 minutes, that's uhhh 16 hours straight winding. I might cry a little

 

[auraslip]

This guy wants to win the next race and I want him to too

 

[Farfle]

Winning would be a plus for sure, but I want at least 1st-5th place taken by electrics.

 

[Farfle]

2.5 down, 18.5 to go. on the first phase...

 

[parabellum]

Hi Farfle. Why are you winding 123123 or every third tooth? The phases usually go covering segments with specific toot count, where each following tooth is inverted polarity but same phase.

 

[Farfle]

Thats a good question... Should it be wound that way?

 

[parabellum]

Have you unwound at least 1 phase of original pie to get the sequence?

 

[parabellum]

Here is the picture of HS motor with 1 missing phase for reference.

 

[Farfle]

Nope... Aargh... If it helps, it has 56 magnets, 56 poles and 63 teeth.

 

[Farfle]

Ok, I found some pictures of the motor before I stripped it, not sure what can be discerned from it.

 

[parabellum]

Nope... Aargh... If it helps, it has 56 magnets, 56 poles and 63 teeth.

OK. It is nice count. It looks like 7 segments of 3 toots. Every firs and last tooth in every segment same polarity Ex. A+-+B+-+C+-+A+-+ and so on (or vice verse)

 

[parabellum]

Ok, I found some pictures of the motor before I stripped it, not sure what can be discerned from it.

Cool, my calcs are right looking the pictures. I was little concerned.

 

[Farfle]

Phew.. What do you mean by polarity, the direction that the tooth is wound? As in cw or ccw looking at the tooth from the outside of the motor?

 

[parabellum]

Phew.. What do you mean by polarity, the direction that the tooth is wound? As in cw or ccw looking at the tooth from the outside of the motor?

Yes, mechanically seen cw/ccw.

 

[Thud]

J,
your winding scheam should be:

AaABbBCcCAaA & reapeating all the way around the stator.
the capital will indicate a CW turn the lowercase is CCW turn.

here is a cheap drawing showing the physical layout:
View attachment farfles motor.pdf

here is a simple calculator to look it over
http://www.bavaria-direct.co.za/models/files/Winding_Scheme_Calculator.htm

 

[Andje]

Thanks for this Thud; I don't know about Farfle but I had yet to understand exactly how to rewind in the right pattern with certainty. For whatever reason you and para have finally presented the knowledge in a way my brain understands.
So you wind all those phases and then at the end you connect them all to give you the three phase wires and the termination bundle.
If you add enough magnet wire to run out the motor to your controller you could end up with uninterrupted phase wires with no solder areas to melt made of bundles of magnet wire, right? Is there an obvious reason not to do this? I have had previous motors fail at the phase wire solder point inside the motor.

 

[Thud]

I have allways wound each phase with a full length of wire. (tougher to do with multi strand winds)

Never have a splice anywhere inside a coil...I have seen guys wind each tooth & solder them all together...but that is time expensive & adds many failure points.

this motor is a realativly simple one to terminate but it can get confusing terminating between delta & wye on some winds.

to avoid confusion...I allways mark where I make my starts....so i only terminate the "ends" of the phase.
hope it helps.
T

 

[Andje]

Thud, you say you wind one phase all at once. Using the "Drive Calculator" program, I get these values;

9895mm is one wire in one phase, so that would cover the three teeth 7 times. So for a 3*7 I would start with 7 wires 9895mm long, then wrap AaABbBCcC.
Im thinking of setting it up for Delta/Wye, so I'd end with 6 wires in the motor, then I could terminate as I wanted depending on my final top rpm/speed ratio.
Does that all make sense?

 

[Thud]

I concur
here are a few tips to keep you on track:

to clarify: 1 wire for each phase (or group of 7 in your case) & only wind the phase teeth for which that wire is designated.
1st All the As
next all the Bs
then all the C's

I write all the phase letters & proper capitalization where required on each tooth of the stator with a sharpie....you'll be amazed at how easy it is to loose track when jumping 6 teeth to keep winding your 1st phase. Keep a note on how you clamp your stator for winding & make certain you don't revers it when re-positioning.

Hey Farfle,
what formula did you use to estimate your new KV expectations?

I also find the stator calculator is overly optomistic regarding my winding skills. I can normaly only get within 1 turn of what it says I can
example: my 80-100s with 2P 14g. it says I can make 8 turns...I can only get 7 & still wind all 3 phases.
(puny human!)

 

[parabellum]

If you add enough magnet wire to run out the motor to your controller you could end up with uninterrupted phase wires with no solder areas to melt made of bundles of magnet wire, right? Is there an obvious reason not to do this?

If you use Delta, it can be wound all with 1 wire till controller, only joint will be start and and of the wire. Tricky part in some cases is getting them trough the axle hole or groove.

 

[Farfle]

Thanks so much for the help guys . I didn't use a calculator, I just based it of the original winds. 7.44 with 6 turns, if you double the width it gives you a kv of 7.44 with three turns. I rewound it with two turns for a kv of 11.6. And yes, statorcalc is way optimistic. I thought a 3x3 wind was possible, nope, it didn't fly, was just able to do a 2x4 in wye instead of a 3 turn in delta.

 

[Andje]

Can I ask, what ratio did you get in terms of total wires you could jam in in little 4 inch long pieces straight during a test vs. how many wires are now in your coils?
Stator calc gives me 3*7 and I can fit 42 wires in the slot, although that is truly crammed. I figured with careful winding I would be able to get the same number through the slot. I guess I should test wind a tooth.

 

[Farfle]

We actually were able to fit almost 19 pieces of 16 awg thru the slot without nomex paper. 16 with nomex paper is a helluva accomplishment. We have to use multiple wooden implements to force the wire to go where we want it.

 

[Farfle]

Ok, take two, am I doing this right?

 

[parabellum]

Ok, take two, am I doing this right?

It will work as well, but I would invert it. Other way you get less cooper doing nothing, less resistance do to shorter wire. Invert means, ends coming out from outer side of the section.