How does a router speed controller work?

[64FJ40]

Anyone claim to know and care to explain?

And more specifically, could I use one to slow down my old wood-cutting bandsaw (benchtop 110V) to cut metal?


Thanks,
Eric

 

[Comet]

No you can't use it on a band saw motor. Very different types of motors. I think the router speed controller is just a rheostat.