Rewinding the R-Spec

This gives me hope for my R-SPEC 245 i have from a while ago, as well as another R-SPEC 190 i have with bad windings.

So when you’re done winding and have the winding leads left hanging out there, how do you re-attach the main leads that will plug into the ESC? just solder them together and heat shrink over it?

Pretty much. I even put some small heatshrink over the strands from where they exit the coils all the way to where i soldered them to the main leads. Just to eliminate the problem that the lead to the rewind in the first place.

I’d give you a picture of how it looks, but unfortunatly i used a crappy screw to lock the stator to the bearing tube which broke when i screwed it in, so it’s currently permanently locked in place until i can drill it out. :stuck_out_tongue:

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according to that diagram, 2,4,6,8,10,12. are just wound and left independent? theyre not crossing any other windings? ive never wound a motor before so its a basic question im sure.

The winding scheme hummie linked is LRK, where you only wind every other tooth and the others are left empty. I used a dLRK wind where all 12 teeth are wound.

This is the schematic i used:

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The winding “magnet wire” is insulated though so u should burn the ends or even scrape them or use some kind of liquid remover to clean it off and then solder. It probably largely comes off soldering but it’s the typical practice.

Thank you, that clears things up for me a lot. I’m going to have to try this one day soon. I have a slowly growing collection of faulty motors now.

Didn’t want to create new thread so problem is loose winding.

Just got my new r-specs and both of them have few loose coil. Should I put some epox on the outer side of stator where loose windings are or maybe return these? I’m from Finland so returnig is little expensive.

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That shouldn’t really be a problem, but if you want to be on the safe side, get some heat resistant epoxy and put a little over the loose strand. Couldn’t hurt.

But something I’d recommend is to put some heatshrink over the phasewires where they coil around inside the can to avoid the same problem me and a few others have had with the insulation rubbing off and shorting out the motor. Might be quite tricky to do though without pulling out the stator a bit, and that’s a whole project in itself.

Yea I think I have to do that. I’ve got some 100 celsius resistant 2 comp epox.

It’s wieird that one motor is perfect but the other… couple of loose winding, motor wires stick out differrnt ways, one wire will be shorting soon due to scrubing and keyway is bad (had to file).

Hellooo guys. Just found this old thread, was basically just about to make a new one. Got an Rspec 6355, riding with it since last year but now it’s borked because of pebbles getting in the motor and crushing the windings… !!

I thought about this before but i have not really seen any threads about rocks or pebbles in the motor so i assumed it wasn’t really any issue. Or maybe it’s usually not but i was being sort of extreme riding around here as soon as the ice on the roads cleared after the swedish winter… We use alot of sand and gravel to keep people from slipping in the winter so… now i know that up to about an inch of gravel, you can still ride, two inches you can still plunge through if you brace for impact! xD

It’s actually really funny and exhilarating ride, skidding along.

But now i probably need to rewind my motor, i have sent a guarantee ticket but i’m not really expecting them to cover this… i mean it’s really not their fault, if it where my company i might cover it if it was super rare, one in a thousand, just to get good reviews. But i’m not counting on it.

So what wire is recommended? I’m looking to reduce the kV a bit, aiming for 170-180 as the single drive is a little too much for my vesc in this hilly area, overheats just before the top of some hills!

Based of this thread, is the 190 kv Rspec originally 14 turns? would i need 15 or 16 to be close to 170 kv? Guessing 1.2 wire might be good?

I have not had any temp issues in the rspec before the shorts so i’m guessing i can get away with some rookie mistakes in the winding… such as less copper in it. But also i have now printed a protective cover so, it will probably run hotter with that mounted!

If u do even a half decent winding with a single copper wire you’ll likely have less resistance to inductance than before and a cooler motor. figuring what size wire will fit with those turns there’s a calculator u can use if u add a couple stator dimensions.

https://www.rcgroups.com/forums/showthread.php?2228201-Turn-Calculator-7-2&highlight=turn+calculator

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Hmmm alright thanks Hummie. That is encouraging, it is quite daunting to rip up the motor like this. I’ll place an order for some 1.2-1.3 diameter wire nad hope that will be a good fit for 15/16 turns. Will be interesting to run some 50 amps through that, i won’t believe it’ll work until i see it but the motor did take that on before without problems so, i’ll be putting back a similar amount of copper sooo… But in any other application you’d never use that thin wire, more lika 8mm2! haha.

According to the calc i will get 177 kV for 15 turns or 166 for 16. Both should probably be ok. Or maybe even lower and i’ll add some more cells in series, we’ll se how the winding goes.

About the winding, would the dLRK Iceni linked be the stock one? The LRK looks way simple but i mean, if i get it correctly then i will have to put 30 windings on every other tooth!?

That would though be 2x times the dLRK wind so that sort of makes sense. Will it still have the same number of steps only using half the teeth/magnets? It just feels wrong but, yeah hummie i just read through the hubmotor thread (that devin… heh! :D) , you seem to know your stuff.

This is 30 turns. I forget the gauge now. But doing every other tooth in my mind is much easier and likely would get more copper on because since we’re not amazing pros getting jammed up is inevitable. You wana get jammed up! .

If you terminate it wye it’ll drop the kv almost half. Maybe that’s how @Iceni got to so low 250kv with such fat wire 1.45.

I probably said it in here somewherebut maybe not, If u can get the stock motor onto a vesc to get the resistance and inductance numbers from the tests and compare that would be really nice to see.
This 15$ inductance meter is pretty awesome to use winding.

@petter With 1.45mm wire I think i managed to get 12.5 turns on, which turned out to approx 240kv in delta. If I would change to wye it drops to 140-ish. All theoretical though, used a turn calculator to get the values. But the speed tests seems to indicate it’s fairly accurate.

Edit: 1.45mm is with the enamel, the copper is 1.4mm.

So to get around 170 you could go two ways, use even fatter wire and less turns in wye or a little thinner for more turns in delta.

I found that dlrk was easier to manage, with lrk you need to double the turns on the teeth you use which can get messy. And the inner ocd in me couldn’t stand leaving teeth open :stuck_out_tongue:

Haha yeah I feel with your OCD there! In fact, i might have to do this with my eyes closed so i don’t fret too much about it!

I don’t quite like the wye, i tried re-terminating two previous motors and while they still worked they didnt quite feel as solid after. But i might be imagining that, breaking them open and messing about not quite knowing what i was doing, hehe. But i think i’ll go for the delta wind in LRK.

One thought i got is, LRK should build more height than dLRK! Winding the same tooth twice as much should be OK in the slot, but we’ll see about the top/bottom.

@Hummie, Is that the inductance meter you’re using? I’ve seen that before and thought it seemed nice, does caps also right? Then i might get one, now that i’ve actually got a use case for it :smiley:

The only Rspec i have right now is pretty much dickered, but i do have a vesc and i can get the values from there. I’ll also post the new post-wind values. Hopefully the values in the vesc now are from a better point in the motors life, should be at least a month old and, i have not paid super attention to them but i’ve redone the test in BLDC tool a few times, trying to optimize and i don’t remember them differing much.

Edit: Haha! I was just looking for a good magnet wire and then got a pic that was actually accurate and where you could see the scale! 1.2 mm wire is fucking fat man! even though in small for the current… @Iceni, did you have any problems with the enamel breaking off bending such thick wire?

No breakage from bending it, the only time it got damaged was when I scratched it with a hard edge, though I suppose it’s gonna be different depending on the brand you get.

I got mine from electrokit.com. Where are you located btw?

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Here I am giving basic advice and you’re steps beyond me.
I don’t think the extra wire on the top and bottom with lrk would hit anything and you’ve got a lot of room in a typical outrunner Yea the meter does capacitance too.

Haha! I just ordered from electrokit aswell! But the 1.2 mm wire. Also i got two of them since they were 100 grams each and you stated 100 grams copper + 20 more after winding. And I’ll probably mess up/redo some part so some extra will be nice. I’m in sweden(örnsköldsvik), guessing you are to?

@Hummie, haha well not really! I really appreciate both of your inputs, i do a lot of electronics and tinkering but motor/transformer winding still feels like some sort of black magic. The Rspec actually has more room than the other NTM motors i looked at.

I ordered a LC meter on ebay so i’ll measure with that when i get it. Or actually i got two, one generic one for transistors and stuff but the inductor range on that one was something like 1mH - 20 H, ridiculously high so i got a ‘high precision’ LC one also that supposedly does 1nH - 20 H. Almost the same as yours i think but the buttons and input are in another order(the oddities of cut-throat manufacturing in china)

Will be posting the values from vesc and some pictures during the week while waiting for my orders!

Holy hell, got the wire today! :open_mouth:

Also here is a pic of the stator, some of the damage showing

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Nice, now you got the fun part ahead of you, stripping the old wire from the stator :stuck_out_tongue: