I'm going to upgrade my mini Super Sportster to brushless and have just a couple of questions. First, can brushless motors run off of NiCad batteries? I'd like to test my setup with my existing batteries, so if I get a brushless speed controller and motor, is that enough or do I need a LiPo right off the bat as well.

Regarding LiPo, how do I compute the capacity of the speed controller I need. Do I just multiply the max discharge rate (e.g. 20C) of the battery times its maH rating? (e.g. 1800mAH x 25C ---> 45Amp controller). Is it OK to err on the side of caution and get one size bigger ESC if I'm not sure?

And one more question... do Rimfire outrunner motors come with just the flat motor mount with four holes, or do they also include the adjustable mount as well. Best i can describe it is a bracket that mounts to the firewall, then you attach the motor to the bracket allowing lateral and vertical adjustments. I didn't see any mention of the latter in the online manual for the motor.

Thanks.

I think you would be better off asking this in the Electric aircraft forums. This is a little too advanced for the newbie forum IMHO.

Brushless can run off of NiCad no problem. DC voltage is DC voltage no matter what the source.
Capacity for sizing a speed controller is more a function of what the motor will draw not what the battery can deliver, however not knowing that and as long as your plane can handle the weight you can't oversize an ESC, your calculations are a good place to start.
Someone else will have to chime in an the RimFire question.

Yes, although LiPo's maintain a higher voltage throughout the run time so your results will not reflect what you would see with a LiPo setup.

If you want to increase performance, go the other way... switch to LiPo or NiMH NOW ( if the ESC can handle the extra voltage ), then see if you also need to upgrade to brushless.

You'll get better performance moving to LiPo.

Well that will give you what the battery is supposed to put out at max, but what if you put in a larger battery later, or a bigger prop which will draw more amps?

And what does your actual combination draw now?



What you are doing is a good starting rule of thumb though, and if you add a margin for safety you will always be safe.

So, yes you COULD safely go with a 45A controller.

But also remember that the Mini Super Sportster draws no where near 45A. A 25A ESC is MORE than sufficient. Even a 15A ESC may be enough.

What you need to figure out is how much your motor and prop can and will draw a maximum then work backward from there.



Yes

No, either this is provided with the plane or seperately purchased.