winding a motor

[montess]

Oh ok.

[montess]

Thanks for that post, I did two 540 motors w/ the medium wire in the radio shack pack and got 75 turns, could have went more but I left it at that. Then I did two more with the smallest wire and went 125 turns, could prob. go 200 turns the 125 was about the same as the 75.

[JohnRobHolmes]

Originally Posted by montess

Thanks for that post, I did two 540 motors w/ the medium wire in the radio shack pack and got 75 turns, could have went more but I left it at that. Then I did two more with the smallest wire and went 125 turns, could prob. go 200 turns the 125 was about the same as the 75.

what do you mean by the 125 was the same as the 75? does it spin the same speed? what about the amp draw? you should try to fill up the armature with wire as much as possible for efficiency. if you wind it too high your amp draw will be so low that you will need more volts than the armature can handle in order to get usable power.

remember this- a 540 can motor can only produce so much power. it doesnt matter how many winds or how big the wire is (assuming you fill up the armature with wire). the only difference that winds really makes is how many volts and at what amperage the motor produces X amount of power. you can make a 55 turn act like a 12 turn- just add enough voltage to get the rpm as high. the amp draw will be much lower though (longer runtime)

[JohnRobHolmes]

Originally Posted by montess

We all have problems with stalling with our clodbusters, due to, what Ive read that the copper wire in the winds gets hot there for makeing it stall, so if I were to wind the motor that will be on the back axle a couple more times that should help the stalling by increasing the torque a little bit and running cooler? But would that cause any other problems? I am going to start winding two stock clod motors tomarrow.

if you did this the rear motor would be slower and have LESS power. unless you dropped a higher voltage across it. like i said ealier, more winds = less amp draw. less amp draw = less power if you keep your voltage the same. crawlers are geared down so much that they hardly need any power to crawl.

[SR5Dave]

Originally Posted by johnrobholmes

if you did this the rear motor would be slower and have LESS power. unless you dropped a higher voltage across it. like i said ealier, more winds = less amp draw. less amp draw = less power if you keep your voltage the same. crawlers are geared down so much that they hardly need any power to crawl.

Less RPM but not less torque. My 55T lathe motor have as much torque as my 12T Puller motors.

[RockDragon]

http://www.rcpics.net/img/48068

Well after I read this post, I picked up an old modified motor that was in my junk box. I used it on one of my touring cars before. It is 11 turns Triple winding (the one on the right).
@ 7.2 volts, it turns out 41,000 rpm and takes about 10 amps (free spinning without load).
Then I replaced the armature with the one I winded, 60 turns single winding )the one on the left). I used the 27 SWG enamelled copper wire (0.4mm dia.) winded around the other old armature that I removed away the old triple 15 turn wind.

These are the results of the single 60 turn winding (free spinning without load).
@ 7.2 volts 7290 rpm 0.71 amp
@ 4.8 volts 4830 rpm 0.67 amp

And you know what .... I lowed the voltage down to see how low it will keep spinning. It stopped spinning at 0.6 volt.
@ 1.2 volts 1080 rpm 0.56 amp

(All testing motors timing are set at 0 degree.)

I will have to put it on my TLT and see how much power it can deliver out.

[JohnRobHolmes]

Originally Posted by SR5Dave

Less RPM but not less torque. My 55T lathe motor have as much torque as my 12T Puller motors.

is this gearing the same with the same output rpm? they should have the same torque, but it will be at different operating voltages and amperages. the higher wind motor might have more initial torque from the tighter winding and better electormagnetic field structure.

i by no means claim to be an expert, but the way that i understand it you cant just produce torque or power from different winds- only from different motor construction (efficiency, magnets, can size/length).

[DWiddowmaker]

Could I wind a 40 turn, and still have good torque like the lathes but have a little more RPMs? And if so what gauge wire should I get to wind a 40 turn in a 540 can?

Thx,
Corey

[JohnRobHolmes]

DWiddowmaker, i dont know what gauge to use of the top of my head. i just get my enamel coated wire from radio shack. im not sure how many turns you could get with the biggest wire.

a 35 to 40 turn would be a good compromise between speed and power.

now i have myself all confused on motor theory, and what REALLY gets changed with different wiring (other than rpm/volt). i need to do more studying.

[RockDragon]

I found a few web pages that talk almost evrything about the MOTOR.
I hope these informations could help us understand a lot more of how we can modify our motors to suit our needs.

http://www.reliance.com/mtr/mtrthr.htm

http://www.sonic.net/~sjl/motor.html

http://canadianelectricflight-com.ca...%20theory'

As for the spec of the wires, I found good info from this site.

http://uk.farnell.com/jsp/endecaSear...erDisplay=true

Hope these will help.

[JohnRobHolmes]

great links dragon!

the canadianelectric one had the formula i was looking for. torque = Kt x amp draw. the Kt (torque constant per volt applied) goes up with more winds, but the amp draw goes down per volt applied. so without actually testing a motor with different winds with everything else the same (can, armature, brushes, bearings, magnets, etc..) i can't actually say whether a motor will produce more torque overall when you wind it up. every motor will be different because of the magnets and efficiency charateristics. each individual motor setup will have a "perfect" wind number that maximizes power and efficency.

what i CAN say is that lathe motors have much stronger magnets than most motors, and therefore will produce more torque (keeping rpm constant with applied voltage adjusted to suit the motor's rpm per volt -a.k.a. Kv).

also, for another example, lets vary the input voltage and rewind a figurative motor with an rpm limit of 30,000.
---the lower wind motor will produce more initial torque, spin faster, but it will also draw a lot of amps. its max rpm will occur at a lower voltage and higher amperage, and the greater initial torque is created from the higher stalling amp draw.
---the higher wind motor will produce less initial torque, and draw less amps throughout its entire rpm range but at a higher voltage. what this accomplishes is a greater efficiency at higher rpms (from the lower amp draw, less heat = better effeciency) and the higher wind motor will produce more torque in the higher rpm range than the low wind motor.

there is voltage, amperage,Kv, Kt, and efficiency all mixing in to this. all we need to know is that higher wind motors work best for our application! of course you could just gear down a fast motor- but then you would still sacrifice runtime.

i dont know if this even helps anybody- i just started rambling.

[BigSmokinGun]

Originally Posted by johnrobholmes

great links dragon!

all we need to know is that higher wind motors work best for our application!

Thats all we need to know...WIND AWAY MEN!!!

[CrawlinForLife]

For you clod guys, you can do a 40 turn in the front, and a 45 in the back and overdrive the front. That would help the front pull harder. Hmm I might have to wind some myself. I have some 550 titans that could be reworked.

[Rockpiledriver]

This is a great thread!

I've been running Mag mayhems and gear reductions on my clods. I'm very happy with the way they work, I do not experience ANY stall. They perform almost identical to a shafty without the torque flex. But, the reduction boxes are big, bulky, and restrict link placement so I want to try more winds and no reduction.

Does anyone who has wound their own motors for a clod have any results compaired to say stock cans, or lathe motors?

[JohnRobHolmes]

a clod with lathes and 9t pinions is perfect on 6 cells for my taste. if you wanted to use more cells then you could wind the motors more, like 75 winds.

keep in mind that stronger magnets in your motor will give you MUCH more torque than just high winding counts. lathe motors have very strong magnets.

[SlammedMini469]

so what if u got some lathe motors and rewound them to, say, 75-80 turns?

[SR5Dave]

You can also buy strong magnets for fairly cheap. Talk to your LHS about ordering some magnets from some Cobalt motors or something.

[SlammedMini469]

Originally Posted by SR5Dave

You can also buy strong magnets for fairly cheap. Talk to your LHS about ordering some magnets from some Cobalt motors or something.

http://www2.towerhobbies.com/cgi-bin...lt&FVPROFIL=++

trinity cobalt? astro flight cobalt? :?

[SR5Dave]

Astroflight There may be some stronger ones out there, but that's the best that I know of.

[SlammedMini469]

do the astroflight magnets fit into any can? :?