• Welcome to RCTalk! 🚀

    Join the #1 RC community where hobbyists connect, share, and get expert advice on RC cars, trucks, boats, drones, and more!

    • Friendly & passionate RC enthusiasts
    • RC tips & troubleshooting
    • Buy, sell & trade RC gear
    • Share builds & upgrades

Brushed motors are fun

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
So I don't remember much about electronics class. But I know the wire we used to make the buzzers was super thin stuff. So what is the benefit of going with the smaller wire on your motor? Less weight? Would that not dik with the torque, the magnetic field, etc?
Basically if you have the same number of turns, smaller diameter wire has more resistance. The cycle will be faster but torque will be reduced since the overall volume of wire is as well.
 
Last edited:
Basically if you have the same number of turns, smaller diameter wire has less resistance so the cycle will be faster over the same distance but torque will be reduced since the overall volume of wire is as well.

Smaller wire is less resistance? You get that backwards?
 
I did type that backwards....am enjoying some of those flu like symptoms the news keeps talking about...probably shouldn't answer too many technical questions today...
Ok. So I kinda got ya. But why wouldn't it be just as good to remove some of the bigger wire to get to 17.5t? What difference do you see in wire size changes?

Sorry. I've never toyed with this kinda deeper dive motor tech stuff. I just cleaned, re-lubed, shimmed, etc when I was toying with brushed motors in my 20's, and I really enjoyed it. We could tweak a few things and see big improvements. So this is very interesting.
 
It's about tuning the motor to get what you want out of it. Reducing the amount of wire decreases the magnet and increases speed so there is a loss of torque, and a gain in top speed. Playing with wire thickness instead of just adding and subtracting turns allows for more fine tuning. My goal with the 540 is trying to find a sweet spot with less wheel spin off the line and in the corner with a usable mid range torque still intact. This motor actually feels pretty good, I might have been better to even add a turn for a hair more bottom end. I might try and get that back with a move on the pinion.
 
I have a decent base to be able to play with these motors. I have no formal electrical training however. A lot is guess work based on previous motors, and some knowledge of how the current motor performs vs what I want it to do. With slot cars I really pushed the smaller wire and less windings etc. Eventually you gain heat and smoke instead of top end. Personally I believe actually doing it is 1 of the best ways to learn, and is a part of the hobby that adds a lot to the experience. There is a lot of satisfaction in building a kit, and more still the first time you wind a motor successfully and get to watch it run around the track. Like I said, I am not working with any specialized background for this stuff...if I can do it, you can do it ...in this case.
 
I have a decent base to be able to play with these motors. I have no formal electrical training however. A lot is guess work based on previous motors, and some knowledge of how the current motor performs vs what I want it to do. With slot cars I really pushed the smaller wire and less windings etc. Eventually you gain heat and smoke instead of top end. Personally I believe actually doing it is 1 of the best ways to learn, and is a part of the hobby that adds a lot to the experience. There is a lot of satisfaction in building a kit, and more still the first time you wind a motor successfully and get to watch it run around the track. Like I said, I am not working with any specialized background for this stuff...if I can do it, you can do it ...in this case.
I have a few 540's in there I'll likely never use. Maybe when I get bored I'll tear into one. I really enjoyed working on the little 24th slot car motors.
 
I have a decent base to be able to play with these motors. I have no formal electrical training however. A lot is guess work based on previous motors, and some knowledge of how the current motor performs vs what I want it to do. With slot cars I really pushed the smaller wire and less windings etc. Eventually you gain heat and smoke instead of top end. Personally I believe actually doing it is 1 of the best ways to learn, and is a part of the hobby that adds a lot to the experience. There is a lot of satisfaction in building a kit, and more still the first time you wind a motor successfully and get to watch it run around the track. Like I said, I am not working with any specialized background for this stuff...if I can do it, you can do it ...in this case.
Good stuff. I never got into rewinding motors. I'm enjoying your posts. ;) ✅
Do you have a motor lathe lying around somewhere that you are gonna whip out next?
 
I used to have a wood lathe quite a while back. Used it to make a lot of really nice tobacco pipes....making sure to cement my place outside the modern world,lol.
20251226_074858.webp
 
Wow, this takes me back. I'd never rewind a motor, but cool that you took on that project. Did you remember to break in the brushes and lube to bearing/bushings? Why do the current brushed not require the capacitor and 2 resistors? IDK, that was a thing in my day. I think it was for glitching? Not sure.

Speaking of educational class. In my physics class, highschool. Our assignment, think the lab bit. Was to build a motor. I told my lab partner "I got this" and ours were the first to get done and running. 10pts extra credit. Heck yeah. Other than that? I kinda sucked at physics. HA
 
Wow, this takes me back. I'd never rewind a motor, but cool that you took on that project. Did you remember to break in the brushes and lube to bearing/bushings? Why do the current brushed not require the capacitor and 2 resistors? IDK, that was a thing in my day. I think it was for glitching? Not sure.

Speaking of educational class. In my physics class, highschool. Our assignment, think the lab bit. Was to build a motor. I told my lab partner "I got this" and ours were the first to get done and running. 10pts extra credit. Heck yeah. Other than that? I kinda sucked at physics. HA
Even on an rtr motor lube and breakin is usually first on my list.
I had the same questions about the caps on the back of the motor. Been digging into that a little recently. It looks like the caps built into a modern esc may serve the same function just in a new location. My sr27 is too small to accommodate these ideas at 1/27 scale, so it has the std caps soldered on the back of the motor.
 
I got the current motor apart on my tt02. If anyone with more knowledge can answer this 1 ...
The motor has been running really hot. I assumed it was related to gear ratio, and was going to correct that. It's an after market rebuildable 540, so I took it apart to look at everything. Two of the sets of laminations have deep gouges, the 3rd does not. They are not uniform in size or shape. I would imagine this to be a manufacturing defect. Could it also have an effect on my temp?
20251229_104822.webp
20251229_104842.webp
20251229_104834.webp
 
Back
Top