We were about to throw away one of our kids disposable electric toothbrushes a few months ago and I decided to save it. Even though it might not actually be “ultrasonic,” it might work similarly to an ultrasonic cleaner if attached to a small enough bottle of acetone. Last night I finally got around to trying it. I don’t normally clean bearings if I have spares around, but sometimes you get a new one that’s supposed to be good but just isn’t spinning long enough (pictured here is a “DS” from a relatively new A-RT):
I’ll post if it actually helps. If it doesn’t help, it could just be a bad bearing.
Going to report success here. I’d actually forgotten about it until I looked at the forum and remembered. So I went out to the garage and somehow the thing was still going. The battery was the original AA that was in the toothbrush when we bought it. It outlasted the bristles and still went for 24 hours as a makeshift part cleaner (and there still seems to be some life left in that battery).
And without any real measurement to back this up, the bearing seems smoother than any other bearing I’ve cleaned by just shaking that jar by hand and/or soaking overnight. Also open to the possibility that the PJ Masks helped out in some magical way.
You could also use a Sonicare in whitening mode (which doesn’t seem to have the automatic turn off that it has when you use the “clean” setting) if you don’t have an old kids toothbrush or just wouldn’t want one sitting around for this sort of thing.
