If anyone could help here I would be grateful. What exactly do you look for in an electric motor besides brushed andbrushless?I have a couple of them, my father gave them to me, they are brushed and they have various verbage printed on the side of them. I'm an electroinics technican for the Coast Guard and am used to seeing specifications written in Volts, Ampheres, Watts, Ohms, Hertz, Farads, etc. However I am not seeing anyof those measurment designations on the side of the motor. How can I figure out what size motor I need, as well as what ECSand battery, for the various kits that I may purchase (as kit building is what I would really like to get into)? Is there a mathmatical formula (I like math) for figuring out what size motor/ECS/battery you need, based on whatthe motor specificatons are,to effectivly power a plane of X weight and Y wing span etc.? Thank you all in advance.

Brett</p>

I'm sorry I can't be more helpful other than providing this link:

http://www.rcuniverse.com/forum/m_7100376/tm.htm

It's a good read, with some links to even more information. It does pertain more to brushless motors, since they are by far the most popular/common electric motors in the hobby today.

You could try the electric flight forum. I think there would be some guys that could answer your questions.

Good luck!

Brett, is there anything at all on the motor can? What size is it (diameter, any current ratings at all, and so on). Were the motors ever used for RC flight?

A Coast Guard ET, eh? Well, I was a CG ET from 1975 until I made Warrant in 1986. I was a Chief, selected for both Senior Chief as well as CWO2. So, I opted for CWO2, which turns out to have been a good choice for me. I retired in 1997 as CWO4. Great career. Are you an instructor at Two Rock?

CGr.

flemflam, in absolutely the most basic terms, what you will find is that there is no standard that motor manufacturers go by to list their motors. The easiest types (for me) are the ones that list the motors by size and kv rating.
For instance, you might see a motor listed as a 35-30-1400. That would break down as follows: 35= motor diameter, 30= motor length, 1400= kv rating, or RPM/volt. That motor would be 35mm diameter, 30mm length, and will try to turn 1400 RPM for every volt supplied to it.
Some manufacturers break their motors down by their equivalent Nitro engine as far as output, so you will see (as in E-flite) a Power 10, Power 25, Power 32, etc. In order to find out their exact output, you need to search the motor specs on their website.
Then, you have the ones that list their motors in terms that seem to have nothing to do with power or size, such as Hacker or Tower Pro.

The main things you need to know, are the dimensions, wattage, kv, amperage rating, and operating range.
Dimensions are obvious, you need to know if it will fit your plane, right?
Wattage needs to be known so you know if the output of the motor is right for your plane. As a general rule of thumb, around 100 watts/lb is usually good enough for trainers, and scale type flight. 150 watts/lb is usually good for scale/sport type flight, 200 watts/lb and up for 3D type flight.
Kv rating is sort of your torque rating. The lower the Kv rating, the larger diameter or higher pitch prop you can run. A high Kv rating will mean higher RPM's, so a smaller diameter or lower pitch prop would be neccessary to avoid overdrawing the motor and ESC.
Amperage rating is important, you can figure the wattage output by knowing amperage draw and supply voltage. Amperage X voltage = watts. You also need to know the amperage draw of your setup to make sure it's within the operating range of your motor/ESC. Ultimately, the prop will determine your draw, but there are other factors involved also, such as kv rating and supplied voltage. A Wattmeter is a MUST!
Operating range is pretty obvious, you don't want to go beyond the motor or ESC's capacities, damage will most certainly occur.

Hope this helps.

I ought to put together a "booklet" on electric powered RC. There is so much information available here and at other sites. And, almost to much to remember it all. And, as mentioned above in post #3, there is also the RCU Electric Forums that can offer quite a bit of information. Good places to check out from time to time.

CGr.

Flemflam - the best advice I can give you is forget the fact that a BRUSHED motor was ever created.-BW