RC India

hi.
recently i rewinded my E-MAX CF 2812 motor..the wire i used is a bit thicker then what was originally used..as a result of which i could make only 7 turns per pole (it is a 12 pole motor)..the motor is running absolutely fine..the problem is that,the speed of motor has tremendously increased.Even at half throtle it's rpm is very high..i didnt exteded it to full throtle otherwise dont know what would had happened..

Will it change the thrust of the motor? if yes please let me know how to choose a propeller for it.

i am attaching the picture which helped me..

Yes, reducing the number of turns increases the rpm. You can use a watt meter and check out the current drawn with a smaller prop and move to a bigger prop based on the original rating of motor assuming you are using a similar gauge wire.

sir thanks for replying
the problem is that i dont have a wattmeter..also what about thrust?

If you increase the Gauge of the rewinding wire you are bound to reduce the number turns of poles.

When you reduce the number of turns per pole and increase the Gauge the motor will now have a higher KV or RPM per volts.

Earlier with 12 turns per pole your motor would have some thing like 1000-1200 KV with now 7 turns per pole it will be say like 2000 KV.

You can use the same motor with a smaller prop than earlier. Earlier you would have used a 8x4 or 9x4 prop now you can use the same motor with say 6x3, 5x5 or say 4.5x4.5. You can now use the motor on a faster plane. Now thrust will be less but speed will be more.

Like what Ashok has said it is very essential that you test it with watt meter on the smaller prop being used so that it does not cross the original claimed wattage handling capacity  

You have some options.
1. Rewind the motor.
2. Operate at reduced voltage (Ratio will be as turn ratio, previous/current).
3. Reduce the pitch and/or Dia of prop to change loading pattern depending new KV.
4. Reprogram ESC if option available.
5. Use self control while flying (Too risky as any time, motor/esc may burn.

:giggle: how do you do that? ???

Keeping the throttle to half/the limit as per visual feedback. Though this is little bit tough and if throttle may be taken to DANGER zone, it may burn.

Augustin, While on simulator, I have seen differents model react differently. Only visual feedback helps me and for level flight, some model are at even 25% and some are at 50-60% throttle.
But unknowingly, I can maintain level flight, and my hand does not go to full throttle in case of first one. So, I think it may be tough but not impossible. However, your hand on various model and vast knowledge is much valuable to us.

Then how I should adjust the model properties so that their performance become same. As a 30+ guy, my reflex have detoriated I think and are practicing in simulator (Minimum 2-4 hours /week) to increase reflex. Then, I should not be too worry about reflex. For higher reflex and precision, I generally use Analog JoyPAD rather that Tx-based Simulator as the finer control is much tough in JoyPAD.

Huh, what a relief....

outlook overhaul required ;D

Well, set the throttle end point to 50%....

thanks everyone for your precious comments..........
.also can his motor be used in pusher planes as now its kv is increased?

regards
hitesh

Already heating up setup is not a desirable setup for a pusher. Though all Motor and prop setup can be used as pusher, take care that the power system is not already heating very warm or hot, further ensure sufficient air draft is flowing through the motor can.

Kalyan I am 40+, I feel I bitten by the bejamin button bug, if I indianise it , 'Pa' bug. :giggle:

may be he can use the same motor in ezfly , as the motor gets enough air to cool down in this model type