So, recently when I did a rebuild on a 1922 Singer treadle base, I was wondering the best way to get the gunk and old crud out of the cone-shaped holes that the Singers use as bearings. (like the ones on either side of the foot pedal)
I bought a wire wheel brush for my drill and modified it. The picture below is after the 2nd modification.
I used a belt sander to reshape the wire wheel.
It worked AWESOME, so I thought I would share.