brushed vs. brushless: pros and cons.

[idaho]

Ok guys I'm new to this side of the hobby, I'm a nitro guy that converted, and I'm still learning about the electronic Rc world, what I would like to know is what are the pros and cons for both brushed and brushless motors. Also what do the turn ratings on some motors stand for? I understand that the kv ratings deal with the Rpm a motor will turn at when supplied with x amount of power and other that And the basic differences in how they are built that's the extent of my knowledge. Any help is appreciated guys.

[z50king]

Sensored Brushless is most efficient and fastest and can have speed controls that can do a lot of things to make the motor run how you want it. They last longer and require less maintenance.
Brushed is smooth and usually used for slow crawlers or trailing. They need rebuilding but can last a long time with good rebuilds
Sensorless Brushless is garbage

The KV ratings are only for no load. Don't expect the motor to turn that fast when installed.
Turn ratings just tell you exactly how many times the wire goes around the stator or armeture inside the motor. Both types of motors have turn ratings. Lower number of turns gives more horse power and less torque. Higher number of turns gives more torque and less horse power, unless you use a speed control that can advance the timing throughout the rpm range of the motor which would give more horse power. We usually rate them in watts, but it is easier to understand with hp and torque

[idaho]

Ok, that was pretty simple, thank you. So what speed controls would allow me to adjust the timing? Other then that you have solved my problems on power plant choices for my 3 scalers I plan to build this winter.

[crawler nut]

Advancing the timing isn't good for the motor. It will run hotter and shorten the life span of the motor. Just get a good brushless motor that will produce torque and speed and leave the timing alone. Tekin did a very good job on the Pro4 and Roc412. They both have tons of torque and are fast as hell. Not to mention they crawl great and are butter smooth.

[The Violator]

In every other aspect of RC brushed motors are dead and buried in all but the most basic RTR things. BUT, in crawling brushed reins king. In terms of horsepower, brushless wins hands down in most instances in all but the worst brushless motors and the highest end hand wound custom made brushed motors we have been lucky enough to come across.


So at first glance brushed motors should be gone. But in crawling that is just not the case. DRAG BRAKE. The ability of the car to keep itself in one spot without rolling. Brushed has the brushes and strong magnets to hold the motor from turning by adding physical friction. Brushless motors will lock up with the right esc, but as soon as you add some power, they break free and roll. Uncontrollably in most instances. So instead of driving slowly down the hill and turning , with a brushless motor you will go flying off the edge. Brushed offers more low end control than brushless motors also ( IMO, but that is from my experience running the best brushed motors available vs. the best crawling brushless systems like a tekin pro4 3300 and esc). The Pro4 is great in a basher go fast scaler, but leaves a lot on the table in the slow creep around area.

That said I run brushless systems in my faster scalers, and Brood handwound motors in my comp cars. When it comes to wind count in brushed motors you need to research the motor builder because not all motors are created equally. The type of motor can, arm, etc can change the power of a motor, so a 35 turn standard Tekin motor and a 20 turn handwound motor with a more advanced design could have the same total rpm per volt, but behave significantly different.

The most common esc I find for brushless systems in crawlers is the Castle Mamba Max pro. Not to big, sensored, and can be found a great prices. It is also backed by castles great warranty and exchange program.

For brushed motors Castle esc's are popular, the MMP is great, but the sidewinder is also great at a lower cost. The Mamba micro, and sidewinder micro also work well. The Holmes Hobby line of brushed esc's are supposed to be great, but I have never ran one so I can only speak as to the reputation on this board. He is a big supporter of the comp scene, and many guys run his ESC's with success.

[idaho]

Ok so the differences are like a four pole vs a two pole motor things like that right? And like a 540 vs 550 can? I'm trying to do as much reading as I can on here to pick this up since my local hobby store sucks for crawler and scaler support.

[Charlie-III]

Originally Posted by idaho

Ok so the differences are like a four pole vs a two pole motor things like that right? And like a 540 vs 550 can? I'm trying to do as much reading as I can on here to pick this up since my local hobby store sucks for crawler and scaler support.

Great info provided to you thus far.

If you chose a brushed motor, you can contact John @ Holmes Hobbies or EddieO @ Br00d motors and tell them:

your rig (type & weight)
type driving (fun, basher, comp)
battery voltage 2S LiPO, 3S LiPO, 6 cell NiMH, etc)
ESC
approximate price range

They can then recommend some motors.

[z50king]

Originally Posted by idaho

Ok, that was pretty simple, thank you. So what speed controls would allow me to adjust the timing?

Thanks. I was trying to keep it simple. The Tekin RS series are the most advanced speed controls available. They have the most variables that can be changed by the user through an interface with your computer. The RS will run brushed and brushless motors. Brushed motors have fixed timing.

The rest of the speed controls mentioned are good, too. Just a note, some crawler specific speed controls have 'rock lock' and other settings specific to sensored brushless motors for crawling applications.

Originally Posted by idaho

Ok so the differences are like a four pole vs a two pole motor things like that right? And like a 540 vs 550 can? I'm trying to do as much reading as I can on here to pick this up since my local hobby store sucks for crawler and scaler support.

I'm a teacher and it's too late to write about the physics right now. A two pole will have more hp and less torque. A four pole will have more torque and less hp. A four pole should be smoother.

540 is the standard for most of us and most of 1/10 rc. The 550 is a longer can. They are usually low turn motors with a lot of torque and somewhat higher rpm. It depends on the wind of the 550 can as to how it runs.

The people at the hobby shop should be able to tell you what each type of motor can do and you may be able to take that info and apply it to your crawling application

[idaho]

Wow, thanks guys I now know pretty much all of what I needed to figure out and I feel a lot better about choosing my motors, it's nice to have a forum like this with no local support to speak of. A big thanks to z50king and the violator for taking the time to really explain this to me.