Modify your stock motor, mod motor, any motor!
#1

I am starting this thread to get educated about everything about motor. (i.e. soldering the capacitors, dyno, cutting comm...)
the first thing I would like to know is cutting comm. Is the copper part where it looks like a small hat the comm? How is cutting it make the motor run faster? what kinda comm cutter do you recommand? is integy's Egale any good? or Hudy's?
Second thing Dyno, what does dyno means anyway?
Soldering capacitor: How do i do that???? what does capacitor do in a motor? Preventing it from overloading on current???
Brushs: how often do you guys replace the brushes???
the first thing I would like to know is cutting comm. Is the copper part where it looks like a small hat the comm? How is cutting it make the motor run faster? what kinda comm cutter do you recommand? is integy's Egale any good? or Hudy's?
Second thing Dyno, what does dyno means anyway?
Soldering capacitor: How do i do that???? what does capacitor do in a motor? Preventing it from overloading on current???
Brushs: how often do you guys replace the brushes???
#2

The small copper part is the comm. Cutting doesn't make a motor faster, it restores the performance that is lost as the motor wears. To make the best power, the comm must be absolutely round and clean bright copper. After some use, the copper wears. The wear isn't exactly uniform, the copper wears more in some spots than others. Once the comm gets out of round, the brushes are bouncing instead of riding smoothly, and not delivering the full current that they should. Cutting the comm on a lathe will restore the clean highly conductive surface and make the comm perfectly round again.
Dynos are simply instruments that measure the power output of a motor. Various models use different methods to measure the power. They basically measure torque at various RPM's and calculate horsepower and efficiency based on that info.
You'll need three capacitors, solder one from the positive tab to the can or endbell screw tab, another from the negative tab to the can or endbell screw tab, and the third from the positive tab to the negative tab.
I replace the brushes whenever they show signs of excessive heat (they'll turn a dark bluish color) or when they get too short. Every now and then I'll have brushes that look fine, but don't run well. If my motor is down on power and I can't see any obvious reason, I'll replace the brushes.
Trips
Dynos are simply instruments that measure the power output of a motor. Various models use different methods to measure the power. They basically measure torque at various RPM's and calculate horsepower and efficiency based on that info.
You'll need three capacitors, solder one from the positive tab to the can or endbell screw tab, another from the negative tab to the can or endbell screw tab, and the third from the positive tab to the negative tab.
I replace the brushes whenever they show signs of excessive heat (they'll turn a dark bluish color) or when they get too short. Every now and then I'll have brushes that look fine, but don't run well. If my motor is down on power and I can't see any obvious reason, I'll replace the brushes.
Trips
#3

Well said by trips! Although, if you have certain motors such as a Trinity P2K or GM3, you don't need to solder caps on.
#4

Trips,
Thanks for all the info. I keep hearing/seeing on the posts people saying "I cut the comm on my motor and it can keep up with the mod motors" makes me think it make the motor go faster.
So when someone says Dynoing a motor. It just means measuring the motor???
Oh... What does capacitor do anyway?
Thanks for all the info. I keep hearing/seeing on the posts people saying "I cut the comm on my motor and it can keep up with the mod motors" makes me think it make the motor go faster.
So when someone says Dynoing a motor. It just means measuring the motor???
Oh... What does capacitor do anyway?
#5

Measuring, changing something, measuring again, changing something, measuring again...
The capacitors on the motor are there to reduce electrical arcing (sparking) between the brushes and the commutator. Wenever an electrical contact is made or broken, a little spark is created. The commutator and bushes on our motors make and break contact constantly. The arcing causes faster wear of the comm and brushes, creates heat, and also creates electrical noise which can cause radio interference. The capacitors pretty much take care of those problems.
Trips
The capacitors on the motor are there to reduce electrical arcing (sparking) between the brushes and the commutator. Wenever an electrical contact is made or broken, a little spark is created. The commutator and bushes on our motors make and break contact constantly. The arcing causes faster wear of the comm and brushes, creates heat, and also creates electrical noise which can cause radio interference. The capacitors pretty much take care of those problems.
Trips
#6

Trips,
Thanks for clearing that up.
One last question though. Won't the comm being cut too thin after a while? Do you replace the comm or just replace the whole motor?
Thanks for clearing that up.
One last question though. Won't the comm being cut too thin after a while? Do you replace the comm or just replace the whole motor?
#7

Yes, eventually the comm wears down to where it is too small. When the motor is new, the comm is usually somewhere between .288 and .294 inches in diameter. Once the comm gets down to around .270 I won't cut it again.
At that point, I'll either buy a new motor, or just replace the armature. I'll usually just get the new motor, to have fresh magnets.
Trips
At that point, I'll either buy a new motor, or just replace the armature. I'll usually just get the new motor, to have fresh magnets.
Trips
#8

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#10

Yeah, what gives? Am I to believe the guy with 1,200 posts still wants to know if the comm is the part that looks like a little hat??
