Well, the job is done. I got tired of worrying about discharging the battery too much and then waiting for it to recharge, so I dug through my junk pile and found an old 12 volt transformer from some long-forgotten piece of electronics. It was only rated for 1 amp, but I figured it was worth it to sacrifice it to the cause, so after checking everything out with a multimeter, I hooked it up and let it run. A couple of hours later, the transformer was toast and the second piece was clean. If you're going to do something like this, a power source with adjustable voltage and current would be really nice.
