HELP! New brushed motor slow (after break in)
03-24-2016, 06:45 PM
#1
HELP! New brushed motor slow (after break in)
OK guys,
I played it safe and just bought another brushed motor. I got the Traxxas Titan 550 12T. I put it on my truck as soon as I got home from the store just to see what kind of speed I could get. The truck was noticeably faster. Not a wheelie monster, but definitely an improvement over the 15T motor the truck originally came with.
So here's the problem, I put it in the truck just to see what kind of performance I could expect. It was fast. I then took it out and proceeded to break it in. I put only the motor in a bucket of water and began to run the motor. I ran it at a nice slow RPM and gradually increased the RPMs. I put it through two battery packs repeating this process. Eventually I got the motor up to full throttle. The wires began to get hot and so did the ESC. The wires from the ESC to the battery were so hot I could not hold them for any duration of time. After going full throttle a few times, the esc limited the amount of throttle I could give the motor. I assumed it was because things were getting hot. I quit running the motor at full throttle from there forth, but mostly because even when I gave it full throttle, the RPMs never increased.
So today, I charged my pack, put the motor back in and the speed just wasn't there. I thought breaking in your brushed motor was supposed to improve the performance and longevity. What's going wrong? I shut the thing off for a few min thinking the ESC just needed to reset, but the speed problem was not fixed. It seemed as if it could only get to about half throttle. Anybody have any idea what happened? Did I Screw my ESC? Did I screw my motor? Maybe both? is there any way to check the brushes on the motor, meaning can it be taken apart?
I played it safe and just bought another brushed motor. I got the Traxxas Titan 550 12T. I put it on my truck as soon as I got home from the store just to see what kind of speed I could get. The truck was noticeably faster. Not a wheelie monster, but definitely an improvement over the 15T motor the truck originally came with.
So here's the problem, I put it in the truck just to see what kind of performance I could expect. It was fast. I then took it out and proceeded to break it in. I put only the motor in a bucket of water and began to run the motor. I ran it at a nice slow RPM and gradually increased the RPMs. I put it through two battery packs repeating this process. Eventually I got the motor up to full throttle. The wires began to get hot and so did the ESC. The wires from the ESC to the battery were so hot I could not hold them for any duration of time. After going full throttle a few times, the esc limited the amount of throttle I could give the motor. I assumed it was because things were getting hot. I quit running the motor at full throttle from there forth, but mostly because even when I gave it full throttle, the RPMs never increased.
So today, I charged my pack, put the motor back in and the speed just wasn't there. I thought breaking in your brushed motor was supposed to improve the performance and longevity. What's going wrong? I shut the thing off for a few min thinking the ESC just needed to reset, but the speed problem was not fixed. It seemed as if it could only get to about half throttle. Anybody have any idea what happened? Did I Screw my ESC? Did I screw my motor? Maybe both? is there any way to check the brushes on the motor, meaning can it be taken apart?
03-25-2016, 09:31 AM
#2
Those Titans are not meant to be taken apart. You probably could bend the tabs back and pop the endbell off but once you do you won't be able to do anything. You can't buy new brushes or anything so there's not much point besides to dissect and inspect. The only thing you could possibly do is polish up or cut the commutator if you have a motor lathe. And have fun getting it back together if you do take it apart as you'll have to find a way to hold the brushes away from the commutator to reinstall the endbell.
Also so you didn't break in the motor correctly. The purpose of breaking in a brushed motor is to wear the brushes into the commutator. You want to do this at just enough speed to wear the brushes without getting hot and ruining the commutator surface. The generally accepted way to do this is to power the Titan with a 9v battery (motor direct to battery) while its submerged and run it until the battery is dead. A 9v is used because it provides enough voltage to get some rpm out of it and start wearing the brushes. But the 9v won't provide many amps so there won't be as much arcing and heat to screw up the commutator. Obviously you didn't provide as good of a break in environment hooking it up the vehicle esc and battery as it can supply way more amps and you ran at full throttle. The fact the esc itself and the wires were hot enough you couldn't touch them indicates lots of amps were flowing through the motor, the exact thing you don't want during break in.
Did you mess up the motor or esc? If there's still power going to the motor the esc is probably ok, it's usually all or nothing with esc's. If you still have your old motor you can try throwing that back in to see if you still get the same performance as before just to double check the esc. But I'm going with you messed up the break in of the motor and the commutator and/or brushes are not how they should be. Start over with a new motor and this time do the 9v battery break in I described above.
Also so you didn't break in the motor correctly. The purpose of breaking in a brushed motor is to wear the brushes into the commutator. You want to do this at just enough speed to wear the brushes without getting hot and ruining the commutator surface. The generally accepted way to do this is to power the Titan with a 9v battery (motor direct to battery) while its submerged and run it until the battery is dead. A 9v is used because it provides enough voltage to get some rpm out of it and start wearing the brushes. But the 9v won't provide many amps so there won't be as much arcing and heat to screw up the commutator. Obviously you didn't provide as good of a break in environment hooking it up the vehicle esc and battery as it can supply way more amps and you ran at full throttle. The fact the esc itself and the wires were hot enough you couldn't touch them indicates lots of amps were flowing through the motor, the exact thing you don't want during break in.
Did you mess up the motor or esc? If there's still power going to the motor the esc is probably ok, it's usually all or nothing with esc's. If you still have your old motor you can try throwing that back in to see if you still get the same performance as before just to double check the esc. But I'm going with you messed up the break in of the motor and the commutator and/or brushes are not how they should be. Start over with a new motor and this time do the 9v battery break in I described above.
Last edited by Maj_Overdrive; 03-25-2016 at 09:36 AM.
03-25-2016, 01:12 PM
#3
thanks for the reply.
I thought i was doing the break in correctly. All the stuff i watched on youtube didn't say anything about the rpms or amps. I heard break em in slow, if you want a slow motor. I thought so long as i had it in water the motor would not over heat, and i thought that was the only ting you needed to avoid. Obviously not.
I threw the old motor away because it was totally done for or else I would reinstall it to check the ESC. I'm with you though, it's working so its probably fine.
Another note, I propped the RC up to let the wheels free spin. I ran the motor and I could see a small flame in there. I call it a flame, but I'm not sure what it was. It was a faint blue green. And the faster i ran the motor, the more i could see of it. Any idea if this is normal? What is it?
I thought i was doing the break in correctly. All the stuff i watched on youtube didn't say anything about the rpms or amps. I heard break em in slow, if you want a slow motor. I thought so long as i had it in water the motor would not over heat, and i thought that was the only ting you needed to avoid. Obviously not.
I threw the old motor away because it was totally done for or else I would reinstall it to check the ESC. I'm with you though, it's working so its probably fine.
Another note, I propped the RC up to let the wheels free spin. I ran the motor and I could see a small flame in there. I call it a flame, but I'm not sure what it was. It was a faint blue green. And the faster i ran the motor, the more i could see of it. Any idea if this is normal? What is it?
03-25-2016, 04:06 PM
#4
thanks for the reply.
I thought i was doing the break in correctly. All the stuff i watched on youtube didn't say anything about the rpms or amps. I heard break em in slow, if you want a slow motor. I thought so long as i had it in water the motor would not over heat, and i thought that was the only ting you needed to avoid. Obviously not.
I threw the old motor away because it was totally done for or else I would reinstall it to check the ESC. I'm with you though, it's working so its probably fine.
Another note, I propped the RC up to let the wheels free spin. I ran the motor and I could see a small flame in there. I call it a flame, but I'm not sure what it was. It was a faint blue green. And the faster i ran the motor, the more i could see of it. Any idea if this is normal? What is it?
I thought i was doing the break in correctly. All the stuff i watched on youtube didn't say anything about the rpms or amps. I heard break em in slow, if you want a slow motor. I thought so long as i had it in water the motor would not over heat, and i thought that was the only ting you needed to avoid. Obviously not.
I threw the old motor away because it was totally done for or else I would reinstall it to check the ESC. I'm with you though, it's working so its probably fine.
Another note, I propped the RC up to let the wheels free spin. I ran the motor and I could see a small flame in there. I call it a flame, but I'm not sure what it was. It was a faint blue green. And the faster i ran the motor, the more i could see of it. Any idea if this is normal? What is it?
Seeing a spark in the motor is normal ,that's where the brushes are riding on the armature.
You should have bought a rebuildable motor if you was staying with a brush style!
You may need to put alittle oil on the bearing or bushings.
03-25-2016, 04:49 PM
#5
I don't know what videos you watched but I was always told to do brushed break in at 1/2 throttle or less by local racers. The 9v break in is specifically for the Titan 12t and was developed by racers who raced the Slash 2wd in Stock classes looking for any power advantage possible. It also results in the longest life of the Titan.
Think of brushed motor break in like bedding new brake pads on a full size car. You want just enough heat and friction to transfer some of the brush (brake pad) material to the commutator (brake rotor). Unlike brakes though the amps going through the motor play a role in how the brush beds into the commutator, not just heat and friction.
Btw Cbaker65 is right about everything he said except the armature. The armature is the part with the windings, brushes contact the commutator.
Think of brushed motor break in like bedding new brake pads on a full size car. You want just enough heat and friction to transfer some of the brush (brake pad) material to the commutator (brake rotor). Unlike brakes though the amps going through the motor play a role in how the brush beds into the commutator, not just heat and friction.
Btw Cbaker65 is right about everything he said except the armature. The armature is the part with the windings, brushes contact the commutator.
03-25-2016, 05:40 PM
#6
I don't know what videos you watched but I was always told to do brushed break in at 1/2 throttle or less by local racers. The 9v break in is specifically for the Titan 12t and was developed by racers who raced the Slash 2wd in Stock classes looking for any power advantage possible. It also results in the longest life of the Titan.
Think of brushed motor break in like bedding new brake pads on a full size car. You want just enough heat and friction to transfer some of the brush (brake pad) material to the commutator (brake rotor). Unlike brakes though the amps going through the motor play a role in how the brush beds into the commutator, not just heat and friction.
Btw Cbaker65 is right about everything he said except the armature. The armature is the part with the windings, brushes contact the commutator.
Think of brushed motor break in like bedding new brake pads on a full size car. You want just enough heat and friction to transfer some of the brush (brake pad) material to the commutator (brake rotor). Unlike brakes though the amps going through the motor play a role in how the brush beds into the commutator, not just heat and friction.
Btw Cbaker65 is right about everything he said except the armature. The armature is the part with the windings, brushes contact the commutator.
03-26-2016, 10:47 AM
#7
Thanks guys. The motor is squeaky now. And I notice when I let off the throttle, it doesn't really "coast" like it used to. Motor sounds scratchy. Will the oil on the bearings / bushings help both these things? What kind of oil? WD-40? I heard I should try and avoid buying things like cleaners and oils at hobby shops just to get more bang for my $.
03-26-2016, 12:47 PM
#8
Same here buddy! Same here!
For oil, just some regular old 3 in 1 oil from the hardware store is better than wd40. If the 3 in 1 oil helps and you want to get fancy some shops have bearing oil and places that service bikes and skateboards, rollerblades will have fancy bearing oil too.
Yeah with RC you pay a premium for less content because it's for RC. Nitro cleaner is just brake cleaner really. Lubricating oils and grease you can find better deals. The exception is silicone oils for shocks and vehicles with sealed differentials, that's something you don't find in the outside world.
For oil, just some regular old 3 in 1 oil from the hardware store is better than wd40. If the 3 in 1 oil helps and you want to get fancy some shops have bearing oil and places that service bikes and skateboards, rollerblades will have fancy bearing oil too.
Yeah with RC you pay a premium for less content because it's for RC. Nitro cleaner is just brake cleaner really. Lubricating oils and grease you can find better deals. The exception is silicone oils for shocks and vehicles with sealed differentials, that's something you don't find in the outside world.
