Brushless motor winding class

[donhuff]

That’s interesting. I forgot you mentioned a bit about this. I look for a certain KV at times that would turn a certain prop on a certain size hull to avoid going too big on prop on smaller hulls that may cause walking.

Yes Ray, and that's a good reason to select a certain kv, ie. because you have a range of prop sizes in mind for a certain hull.

[ray schrauwen]

If 2900kv has better power, go ahead.

[ray schrauwen]

I was going to say 2 turns but only b3cause the drawing has wires coming out of both ends sort of. It may have been drawn like that for clarity.

[ray schrauwen]

Now I’m thinking 2.5 y

[donhuff]

I was close! I can understand winding the motor easier with the round cross sectional drawing.

I agree with you Ray that picture makes the wind LOOK easier, it is, BUT that is not how we do our motors. That is a CONCENTRATED type of wind. That means that the wire goes around ONE TOOTH ONLY to make a coil!! Look at that pic again to see what I mean. In our motors, we do a DISTRIBUTED type of wind. In it we go in one slot, skip two slots, and go out on the third slot. REMEMBER??? And then the other two phases fill in those skipped slots, so all of our coils overlap each other and it tends to look very confusing.


concentrated vs distributed.jpg

[ray schrauwen]

Ok, I understand.

[ray schrauwen]

I don’t get too much quiet time to myself here so when I go back to my apartment I’ll really go over this and start some carnage.

[donhuff]

Damnit Ray you're right. 2.5 it is.

In my first looks at that picture, I didn't notice that the wire was going out each end of the coil. My fault. And after looking again I still was not positive. So i went out to the shop and got a piece of wire, and wrapped it around my POLE..............ah, finger. Looks like 2.5 to me now.

[T.S.Davis]

Don, it's back peddling to a desired prop. Little too micro managment on my part.

[donhuff]

Don, on the 4 turn DDD example do we end up with three dead teeth again?

Also... that particular arrangement will produce a Kv of X. What ever it is I don't really know. Lets say I use the tach and it comes out at 1500kv or so but I really wanted 1600 for example. Could I just take one turn out of the center coil so that it's 4,3,4? Just trying to make sure I'm getting it.

OK I got you.

Terry, There is no way that I can predict what the kv of a, strange to me, motor will be. It all depends on the combination of parts, poles, and sizes, of all the components on the inside of that motor. I can make a wild ass guess, but it would be based on the knowledge that I have gotten by working on similar motors. If I can do a couple of test winds using one strand of cat5, I can sort of see what it doing and get a baseline to figure from. Then it's a percentage of the length of the wire in the bundle, that a PER TURN change makes in that length. But it's still just a good guess. There are programs that you can use to guess with, but they get to complicated for me.And a 100 rpm change in kv is hard to come by with the low turn counts that our motors are usually wound at.

I see what you're saying with leaving the one turn off of a 6 pole 18 slot motor, changing the kv just 100, and it might work. Do a test wind and find out! They are not hard to do nor to get back out. And it would be good experience.

And I'll say this about it. IF you are dealing with one of our chinese motors, and you are rewinding it, and choose to wind it 434 like you suggest. You will still end up with more total power that the motor had before winding, because NONE of their slots are full. And while typing this I thought of something else, there are no ends to the possibilities if you think "outside the box" and don't listen to the "experts"

"I edited this paragraph and deleted what was here before, because it was all wrong', sorry if any of you read it and wondered what I meant."



But now lets work at it from a different direction.


Suppose that you have this prop you want to run, because it did very well with your stock 2000 dyna. BUT it gets hot in a few laps, and maybe burned up when you tried to go 6 laps with it.

IF you increase the power output and heat handling and dissipation abilities of your motor and SETUP, I'll bet that you will be amazed at how fast that same motor will go with the same kv and prop.

[properchopper]

OK - I have no right to be in this thread - I try to follow what's going on but I have to stop every few seconds and beat myself on the head with a frozen trout to regain my mental composure BUT all this wire winding talk reminded me of my days in the sound reinforcement biz (early 1970's) when I took a tour of the JBL speaker plant and saw the weird gadgets they used to flatwind the speaker voice coil wire - the idea being that they could wind more flat wire into the coil than if round (which then went into the ring magnet gap) to make more efficient loudspeakers. You are all probably way ahead of me on this but I'm in quaranteen/lockdown and ...whatever

Wire 20200517_120523 (1).jpg

[donhuff]

Frozen Trout


Good one Tony, we use catfish in Georgia!

I have read about the flat wire. There are some motors that have used it too. But they are a lot bigger than our stuff.

[ray schrauwen]

Aaah, flat wire by JBL. I remember that too. Fairly easy with a voice coil but who knows with this.

I can’t remember if it was the Cerwin Vega or JBL show when I was a kid at the Toronto Audio show that had a 3 foot diameter subwoofer. They played Ted Nugent’s Land of a Thousand Dances and I was never the same. It gave me the audio bug like crazy! Then I got a Grasshopper, then I made a 23” BlueBlaster and then got addicted.

[TRUCKPULL]

[ATTACH=CONFIG]169219[/ATTACH]


Lets have a little test, to see if ya'll have been understand what I've been preaching about.

In the picture above, I want you to describe the motor to me. It's laid out differently that the way I have been drawing them, but it's still showing you the same thing, only in a more congested but all together and round layout. More like a real motor would look if you were to slice it in half across the shaft.


I want to know. Click on the pic to make it big enough to see well.

1 number of turns
2 number of poles
3 number of slots/teeth
4 and the hard one, wye or delta. This might be a little hard for you because of the way it's drawn, but remember it all about where the ends of the wire END.

Don
Terry said it first 5 Turn.
Is their not 5 wires in each slot??

Larry

[ray schrauwen]

Aaargh!#*%@. I went back and started reading from beginning. I?m having a hard time visualizing the starting of winding the bundles even with pictures in post 1 &2.

I?m really a tactile or hands on learner. I better go butcher a motor, lol. I have to have it in my hands to figure it out.

Sorry I slacked on the reading at the beginning Don, I?m a lazy 👩*!**🎓 student dontcha know? Lol...

More reading. I?ll get it eventually.