I have a 1/3hp single-phase AC motor spinning my drill press. With the maximum reductions available through pulleys it still runs 10x too fast for one of my applications (i.e., the chuck turns at 360rpm and I need it around 30rpm).
I'd be happy to cut the output torque proportionately to the speed reduction, but I've been reading about this for hours and I can't even determine:
- For what types of small AC motors is sustainable speed reduction possible?
- By what means? Triac? PWM? VFD?
- To what extent? Is 10x speed reduction possible?
And then there's the problem that I can't even tell for sure what kind of AC motor I have. I can see that it has a 16µF (run?) capacitor bolted to its side. And here's a picture:
I'm further bewildered because typical hacks for this problem involve hundreds of dollars in gearing or special motors. This entire drill press is $100, so I have a hard time believing there's not a sub-$100 solution. E.g., I'd be happy to replace the motor with one that runs on household current at something like 200rpm instead of this one's native ~1800rpm. But I haven't been able to find even that.
Am I missing some fundamental limitation to producing torque off of household AC at very low rotational speeds?