I bought a set of non-machined all black iro wheels a while back, and now I wish they were machined...

I've recently been having some knee problems, seems like old injuries are creeping back into my life. I also just want a front brake for some of the hills around here.

is there a way to "machine" a rim? I've been thinking about wire wheels, sand paper, paint removers, and plenty of other methods, but I have no clue as to their effectiveness. if it comes down to it, I'll just buy a new rim, but I'd rather not spend any money at the moment.

so yeah, anyone done this? had success with it? am I just pissing in the wind?