Engine RPM

[thierryc]

[color=#000000]Hello all

I have just purchased a bunch of Mabushi RS-550 SH engines. I am looking for their max rpm on 12V and 6 V
I have been on various websites to try to find the right rom but each website was giving me a different values, ranging from 10,000rpm to 78,000 rpm (yeah right).
Would anybody know what is is the correct RPM on 12V and 6V so that I can get the right gear ratio on the prop shaft ??
Thanks

ps]



Edited By ThierryC on 1052244475

[anonymous]

It all depends... these motors

[color=#000000]It all depends... these motors are ALWAYS custom made in huge quantities for specific applications... depending on where they came from, they could be wound several different ways.
Quick trick]

[thierryc]

Thanks a lot for the

[color=#000000]Thanks a lot for the reply !
Using our method, I found that the engines are running at 17000rpm on 12V and at 8500rpm on 6V
The propellers I am going to use have a max rpm of 7000rpm.

Should I run the engines direct drive on 6V or should I run them on 12V with a 1]

[anonymous]

It all depends!
Let's say you

It all depends!
Let's say you run 6v, direct drive. A teeny prop won't load the motor much, and it will spin at 8500 rpm, cavitating all the way. A huge prop will load it down, making it run slow AND pulling lots of amps. How slow? I have no idea. Experiment- make a rig with the motor, shaft and prop, and stick it in a bucket... if the motor gets too hot to hold, you are mismatched! Even better if you can rig a tachometer somehow (I build my own with a photo-interupter and read it on an oscilloscope).
If you run on 12v, you will need a gearbox... again, I can't predict how fast the motor will run then... but if runs at 75% (12,750 rpm), you'll want a 1.8 reduction.
Good luck!
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