FIRST alum from '07 here. I sort of fell out of the scene after high school, but I’m glad to see that it’s grown so much (what is this cRIO and Jaguar shenanigans?!). I have a few things I’d like to hawk to the community - not being too sure which category this kind of post belongs in, so I put it in “chit-chat” for now.
A few of us builders of rideable things up at MIT recently commissioned a custom order of very large R/C model motors. The minimum order was more than we could ever reasonably use, so I figured I would return here and see who else is into building wacky moving contraptions.
Basic specs: “C80” type brushless outrunner, 80mm OD, 110mm length, torque constant Kt ~ 0.053 (or 180RPM/V). 0.021-0.024 ohms line to line resistance. 12mm shaft on both ends. Weighs about 6 pounds.
These things are scarily powerful - typically up to 5-6000W peak mechanical output and more than 90% efficiency. Many electric bikes and go-karts have been made with this type of motor. People have rewound them and pushed 10kW through them for short periods of time. In ground usage, they will not do this kind of power forever because there is no cooling implied. They are “rated” for 7kW in aircraft use where you’re pretty much guaranteed a stiff breeze. Now keep in mind this is a typical R/C industry spec, but this motor has plenty of traction usage behind it.
We have like 5 more of these and would like to see $200 each - PM or email charlesg@ (that 3 lettered university I mentioned) .edu.