Hacking a DC motor to make a generator. RPM vs. Voltage weirdness, gear ratio confusion, and general circuit questions?
I'm hacking an ancient 115 Volt DC water boiler motor to try and make a small, portable, "dremel" generator (meaning it does different things with different attachments). Doing a rudimentary test of it, with a small diode hooked to the wires, I found that it only puts out about .01 volts when being cranked by hand. So I figured I'd put my drill to good use, hook it to the rotor, and let it fly. Through this, I found that after 60 RPM, the voltage goes completely zero, even when spinning at around 220 RPM, nothing. I am completely bamboozled by this, which might have something to do with my limited electronics knowledge and my tendency to try and 'run before I can walk' in new things. I was also wondering if the low voltage could be solved by using gears and gear ratios, but my knowledge of those subjects is very limited indeed. If anyone can explain or converse with me on this, please do! I'd greatly appreciate any and all help.