Need a Huge 63-74 Outrunner Rewound
 

Just as the title says... I will be ordering this outrunner tommoro for my warhead- http://www.hobbycity.com/hobbycity/s...idProduct=3890

Problem is the kv is a little to low. I would like to get it rewound to have around 400-500kv or so but I cant find anyone willing to do it, "including sikeston".

Is their anybody that can help me out with this?

Is there a machine shop around you that could handle it? Also, why don't you want to use a higher voltage to run it as-is? Do you already have the rest of the power system ready?

I really dont want to buy another battery. I like my FlightPower 3200mah 30-60c 5s alot! I just need to get it rewound... Thats all.

I see. Well... You wouldn't need to buy a different battery, just buy another FP 5s 3200. You're looking to have it rewound to about twice the kV, so twice the voltage would run it equally well if not better. I don't know what it would cost to have it rewound compared to the cost of another battery. I suppose a big factor is if you have the ESC yet.

Ya I have the ESC prepped and ready to be ran with this brick. I would much rather run just my 5s because I really dont have a great amount of money right now to be dumping into my warhead project.

Have you considered doing it yourself? I imagine the stator is pretty big inside that motor so it may not be that hard to do.

Now, would it be half as many turns for twice the kV, and just use a larger wire? Or is it not that simple?

Ill be using 22awg wire found in nice 1/10 540 racing motors like sike did. It really doesnt matter what kv range Ill be getting after its rewound as long as its better than what it is right now. If thats the case then Ill try my hardest and maybe Ill have you guys guide me threw this step by step. I really want to pull some power out of my e-warhead conversion and this looks like the perfect motor. Just to low of kv... I also have to grind both ends of the shaft to 8mm to fit the couplers.

Winding isn't too hard, but speeding that outrunner up might cause problems. What target RPM are you trying to get it to hit, and what is the magnet/stator count?

For small wind changes, the kV is tied to winding in a semi linear fashion. It is really complicated to actually calculate them off the cuff though.

Taken from Reliance.com, but there are other forces to be accounted for.

This equation can be further developed to obtain the voltage for movement of a conductor at constant velocity through a uniform magnetic field:
E = NBLv sin P x 10^-8

where:

E = voltage
N = number of turns
B = flux density in lines per square inch
L = length of the conductor in inches
v = velocity in inches per second
P = the angle between the conductor and flux field



You do realize you just ordered a 2 pound motor right? :D

This is why I want someone else to rewind it for me. Im horrible at math and im scared I'll screw up. Oh and no I didnt order it yet. Most likely will though. The motor rpm I want is around 600kv or so... Its a 14 pole, 52/40 size stator.

If you want 500 to 600KV, just get a motor that is in that target range. A 16 ounce motor would be plenty, even a 10 ounce outrunner is a lot for a vehicle.

What voltage do you plan to use?

Plan to use 5s. I had a 16oz 50-55 600kv outrunner but it got to warm for my likings.

Your motor brand choice is most likely the cause of the heat. Buy an axi 4120 in the correct kv and stick with that. Plus your battery is only going to give so much, so a larger motor may over draw the battery. That 3200 will give a max of 96 amps, and with a lower capacity it will not do that for long. I would stick to a smaller motor, and a better built one too.

Try this motor out, I think this is what sike uses in his revo: http://www3.towerhobbies.com/cgi-bin...?&I=LXPPX8&P=7

No I mean the 50-55 600kv only got up to about 120 degrees after a good run in the warhead but didnt have enough power for me. I want more power and thats were the 63-74 comes in. I cant find anything with around 600kv that has the stator size of 50/30 or more.

In that case it may have been either the batteries or the esc. A larger motor will have more torque, but not necessarily more power. Plus spinning a larger stator will require more power as well. I would try an axi, it will be more powerful than you think.

Takedown, are you sure that the motor is the limiting factor?

Since the battery only pushes 96amps, maybe ur Lead finger caused the motor to heat up? :lol:

Hi Takedown,

I just got your PM then I noticed your thread. I think I'll just respond here.

You're right. I'm not really interested in rewinding motors for people. For me, I find it fairly difficult. It's not so hard to actually rewind an outrunner, provided that NO mistakes are made.

What I found to be one of the hardest things, is removing the stator from a motor that is already built. Some Manufacturers use Adhesives similiar to Loctite that require ALOT of heat before they even think about letting go. I baked one in the oven at 500 degrees before I could get the stator off. This melted all the wires together and removed most of the protective coating from the stator.

If you are interested in rewinding a few motors yourself, I do have detailed instructions and diagrams on either DLRK style that you want to go with. Both in Delta Termination and Wye Termination.

On what influences KV in a motor. The larger the Diameter of the stator and the longer the stator, both tend to produce a lower kv motor.

To compensate for this, fewer turns need to be used. This opens up room for more parrallel strands of winding wire to be used. Example: If you remove 10 strands at 20 turns then you can go back using the same Ga. wire for 10 turns using 20 strands.

The goal should be to get the stator poles as full as possible. This makes for a motor that is most efficient and results in cooler temps with less copper loss.

By rewinding, a motor can be changed to perform very different than it once did, BUT.........you also need to consider what you want it to be, then shoot for that.

In raising the kv, using fewer turns and more strands, the internal resistence of the winding is greatly reduced creating a larger load for the ESC to handle.

To achieve a 600kv rating with a 52/40 sized stator is going to be pretty hard. The end result will be beyond your battery's discharge capability and probably beyond your ESC's ability to deliver what it wants. That's a huge motor man.

A custom AXI 4130 using 6 strands of 22Ga. wire and 4 turns makes for a motor that is in the 500 - 550 kv range. This motor has the Wye termination.

The Wye termination makes 1.73 times the torque that a Delta wind does AND makes 1.73 times LESS KV. The amp draw is also 1.73 times LESS than a Delta Wind with the same amount of turns. The Wye also starts better and runs cooler in my opinion. With that being said, this is why I decided to create a 4 turn motor.

It is a hoss! The starting amperage is huge also. Toward the end of the charge, the ESC is getting on the LVC too soon because of the huge amperage (125 - 150amps!) it takes to start this bad boy directly driving the diffs. Consider all of this before you put alot of time into something that isn't going to work.

The 52/40 size stator it TOO big for what you're trying to do. (+ it will explode the diffs). I'm with Linc on this one. Choose something smaller. AXI does make GREAT quality. They use Neo magnets, which is very important when you put one outrunner up against another to compare.

Alot of companies don't use Neo Magnets. This cuts their performance and makes them run hotter.

In cooling this type of setup, think Aluminum for mounts and airflow. I like AXI also because they sell a bolt on fan for "extreme" applications.

You heard the man! Now buy an axi, and stop pissing in the wind!

I can safely say that rewinding a motor looks like a fun job, just not one that I would ever do. I have a feeling that if you step up to a better motor, you will see the increased power and effecientcy, and be very happy.

Hey guys I have a new idea... What if I run dual smaller 42/50 600kv outrunners? They only draw 43a each continious and it seems like a smart idea. One motor for the front diffs and one for the rear diffs. I saw a buggy conversion on youtube like this and it had some real power with really small outrunners running each diff. If I went about doing this I would run it on one ESC on 5s lipo? Im guessing this isnt a very smart idea?

Another option of mine is to go with a smaller motor such as this- http://www.hobbycity.com/hobbycity/s...idProduct=2101

Im guessing thats plenty of power on 5s lipo. And I know my hacker will be able to handle it. So is this the way to go?

you couldn't run this with one esc as the motors will get out of sync and the esc will toast.

I believe two motors / one esc has been done but with a transmission such as the emaxx so that the motors stay in the same orientation. Even then this is hard to do IMO as no two motors have identical kv's.

Hey did you miss this one? http://www.hobbycity.com/hobbycity/s...idProduct=4907

Nitro: I already tried that motor in my warhead and it didnt have enough power for me. I think the 50-65 350kv is the only way to go I guess...

Well i think I know what motor I have my mind set on now- http://www.hobbycity.com/hobbycity/s...idProduct=4914

It has a good kv rating and looks pretty promising.

God I cant choose. I would like this- http://www.hobbycity.com/hobbycity/s...idProduct=4572

But I would like to get a little more kv out of it. Back to sike...

That thing would chew up your truck on 10S!

Is there any reason you do not want to buy the axi 4120 I linked to?

Price? Desire to keep HobbyCity in business, Had a bad childhood experience with an axi?

Sounds like your batteries are too weak. You don't need a 2 pound motor.

takedown, all this conversation leads me to beleive that u need more cells, think about it...
1st off more voltage will cut the amp draw of the batteries
2nd it will allow you to run your snail's pace Outrunner
3rd, it will be more efficient becuase the esc isnt heating up trying to draw 100a from a battery that cant handle it.
4th you will gain even more efficiency by not hauling around a 2 pound motor

hey lincpimp, hes not saving UH-I am! Im getting a 55-55b, 5s lipos, and a charger from them for my Raze! :P

:party:

dang john you beat me to it!
lol

I think I'll go for the Towerpro 64-63 259kv is what I'll get. If and when I get it and its to slow then Ill concider running more voltage.

Haha, well I got some weird news to tell you guys. I went to my LHS today to pick up new yokes for my rustler and walked out with a really nice new JR XP6102 Heli/Airplane Transmitter with 4 pretty new quality receivers. Ill need to sell 3 of the 4 receivers before I buy an outrunner. Linc I am seriously concidering the Axi you showed me. I just have to think about it for awhile. Hope you guys understand. I couldnt pass on this deal!

Woo0t Axi!

Im liking the looks of the Axi 41/30 385kv outrunner. I really dont want to skimp on the motor now that you guys convinced me.

Axi makes a really nice motor, especially considering the price. I have been very happy with mine, and sike has put his thru the paces and likes them too.

Ya I can kinda tell.:lol:

you do realize a heli/airplane controller won't work with car esc's don't you?

according to him he is going to sell them to make some cash or get a heli, he knows

No no no... Im selling 3/4 receivers to afford the axi. Not using the new radio for my warhead. I will be using it for upcoming helis/airplanes.

Now comes the question on if I should sell the Transmitter along with the 4 receivers for $250 plus shipping or if I should keep the transmitter and one receiver and sell the other 3 new receivers for $35 each for when I get a heli/airplane "eventually"...