Hot handwound...

[Duuuuuuuude]

I've been playing around with a handwound 35t motor I made, and I'm really liking it. Not as much runtime as my bl's, but much smoother.

Problem is, it doesn't take much for it to warm up. Regular crawling will get it terribly warm, and if I run it WOT for more than 20-30 seconds (cleaning the dirt off of the tires by bombing around in the yard) it too hot to touch. You can feel the heat radiating off of it.

I'm pretty sure this motor is toast, but before I build another I'd like some input...

I used the biggest wire RS had in thier 3 pack of wire, and powering it with a 3s lipo.

[Robbob]

Gearing? my guess is its simply over geared or somethings binding somewhere.

and that big wire is only like 27g, good for RPM motors to fart around with but not so good for high wind motors you want torque out of.

[Reflection]

So you wound it yourself?

I've wound a ton of my own motors...back in the day anyway. We didn't have allot of options back then,so allot of guys wound their own. One thing I noticed,is winding one yourself,if it's not balanced,it'll heat up faster. The lower wind arms like yours will heat up faster cause they spin allot more RPM's. Taller gears and high voltage will just add to the problem. That plays hell on the brushes and comm. Higher wound arms like a 65-75 turn aren't as bad for heat cause they spin so slow.

There is an art to winding a good arm. Take your time and try to get the winds as even as possible and keep them snug. The truer your arm is,the better it'll run.

[Duuuuuuuude]

Originally Posted by Robbob

Gearing? my guess is its simply over geared or somethings binding somewhere.

and that big wire is only like 27g, good for RPM motors to fart around with but not so good for high wind motors you want torque out of.

Running stock Axial gearing...14/87.

Originally Posted by raptorman57

So you wound it yourself?

I've wound a ton of my own motors...back in the day anyway. We didn't have allot of options back then,so allot of guys wound their own. One thing I noticed,is winding one yourself,if it's not balanced,it'll heat up faster. The lower wind arms like yours will heat up faster cause they spin allot more RPM's. Taller gears and high voltage will just add to the problem. That plays hell on the brushes and comm. Higher wound arms like a 65-75 turn aren't as bad for heat cause they spin so slow.

There is an art to winding a good arm. Take your time and try to get the winds as even as possible and keep them snug. The truer your arm is,the better it'll run.

Yeah, I got bored one day and decided to try it out. Started with a 55t, they did the 35t. The 55 was too slow, but the 35t worked really well. I say "worked" because I smoked it today...lol. Tried to slowly work my way out of a bind and poof, I let all the smoke out. Oh well.

I guess I need to find a bit heavier wire and try again.

Thanks for the input guys.

[JoeMotor]

A real good source for all things handwound. http://www.rcgroups.com/electric-mot...struction-361/

[Duuuuuuuude]

Thanks for the link...I was looking for that.

[JoeMotor]

It's mostly aircraft related, but there is still some great general info.

[Duuuuuuuude]

Yup, not the one I thought it was...still...info is info!

[Henry325]

If you are running 3S, you might want to put more turns on like 55T. You'll get lots of wheel speed using 35T but maybe the gear ratio is never going to be high enough. So, try using thinner wire and go 55T.

[Robbob]

Originally Posted by Duuuuuuuude

I say "worked" because I smoked it today...lol. Tried to slowly work my way out of a bind and poof, I let all the smoke out. Oh well.

I guess I need to find a bit heavier wire and try again.

http://www.bulkwire.com/product.asp?ProdID=7589

22G is what Ive used for my 35T's

cant say its the best or worse but havent smoked one yet

[Duuuuuuuude]

Originally Posted by Robbob

http://www.bulkwire.com/product.asp?ProdID=7589

22G is what Ive used for my 35T's

cant say its the best or worse but havent smoked one yet

Thanks for the tip.

Does anyone know a good cheap source for rebuildable motors? Or maybe I should invest in a comm lathe and start collecting old motors for by builds...

[JohnRobHolmes]

cheap source, ebay!!


You may have had a short to the arm on it, or possibly some binding somewhere. Timing could have played a roll too.

[Duuuuuuuude]

Originally Posted by JohnRobHolmes

cheap source, ebay!!


You may have had a short to the arm on it, or possibly some binding somewhere. Timing could have played a roll too.

I was looking through ebay and found a big lot of oooold racing motors. The price was right, but because of thier age I kinda question the health of the magnets...

Timing was set @ zero. I did notice when I pulled the motor apart last night that a few of the winds on one arm were melted. Could of been a short, could of been just from heat...not really sure. What is for sure is the comm and brushes are toast. One brush broke apart when I pulled it out, and the comm is burnt and has a distinct groove where the brushes ran.