Ok friends, I am back. So let us review. It is E=IR, then power in watts is the product of V and I or V x A or simple VA. So, if you want more power, increase the V or the A or both. In the RC Car world, when you wanted to run the car faster, increase the cells. That would have been increasing the voltage. You have done the same thing by increasing the amps, especially if you were forbidden to add cells. To do this, you will remove some turns to lower the R. You will realize that we only have control over the V and the R really. The AMP draw will be the result.


The now popular KV measure is is really the RPM for every volt and K is just refering to kilo, which is 1000. They say V if to increase speed, A is to increase torque. Well put it this way. Take two similar motors with pinions turning a common spur. Or, join the shafts at two ends. Will you increase the speed. No, you will double the torque. Of course if they are the same motors and you were running them parallel(same cells or different cells), the current draw was doubled. See? double the current and you double the torque and not the speed. If you saw a speed increase, it was because load was halved on the first motor running singly. The RPM of motors is also the result of design like the number of poles and the spacing of the magnets.

When do you increase both V and A? Well, if you merely put more cells, the V went up and since the wires are the same, you have the same R. Current is Voltage/R. So, Amp draw will go up too.

LESSON: When you want more power, get a bigger motor because you can only stretch a small motor so far. You really can't make the Beetle a Benz by putting a Benz grill in front. When you want more power, you can increase the voltage but you have to increase the number of turns to keep the amp draw the same and keep the motor cool. . If you do not want to add turns, the Amp draw will go up and you have to fatten the wire. So, you see, it is putting more wires in there by either fattening it or lengthening it. Either way, you have to put it more bulk into the motor. Precisely, your motor will just have to be bigger to house the extra wires. A bigger diameter motor also add to torque. But since we can convert speed to torque and torque to speed, we can use a small diameter motor but longer and faster. Gear up a high speed motor and you can get torque out of speed. This is how it is done in helicopters. The motors used run up to 3800/V. Look at the gearing. It uses a large spur(wheel) turned by a pinion in the motor. That is why heli motors may not be suited for airplanes. The Blue Wonder brushles comes in 1100,1300, and 1500KV. Many will think the 1500 to be better. Not really, the 1100 turns the same prop size better.

Is stranded wires better than a single wire. Yes, they claim. That is why many motors use stranded wires instead of a single wire. Yet, in a forum, someone swore that the difference is minimal and rewinds motors using single wires. It has something to do with wires in strands has lower resistance than a single wire. The stranded wires tend to break more easily though. TIP:When you wind a motor or even for new ones, use "rugged" thread for maong pants to tie the 3 wires to the stationary case of the motor so you will pull on the thread and not the wires. By the way, before you rewind, dope the cores with resin. 5 mins epoxy will do. This will help to preven abrasion to the enamel coated copper wire and thus shorts to the casing.


P.S. I welcome any corrections from readers if you will just send it to my private email, rcdevices@yahoo.com.ph. For most, pls send your queries. You may request topics too.
Next topics will be ESCs, wiring configuration for multi motor airplanes(parallel or series). Thanks. Oops, errata!K IS NOT FOR KILO NOR FOR 1000. IT STANDS FOR CONSTANT. PLS DISREGARD ABOVE.