I think my Singer 66 Red Eye qualifies for the “Grandma nearly beat it death” category. It appears to have what I call “honest damage” or “damage from use” instead of abuse. It had also suffered from neglect when I got it, but someone had used the machine before that, and probably used it a lot.
It was a Singer 66-1 when I got it. The cabinet hinges were still clamped into it, and there was no sign of it ever having a motor mounted on it (no clean spot on the boss). I would say that it was a treadle machine before I got it, and I doubt that it ever had a motor on it during its life. The face plate and slide plate were both missing and I have replaced them. The upper tension parts were all missing except the center shaft, so I replaced the entire tension assembly. Parts came from a donor machine. I cleaned it with sewing machine oil and mounted an early Chinese hand crank (back when they were plain black without gold decorations) on it, turning it into a 66-3, and put it into an ugly plastic portable case that it still lives in today. I have to remove the crank to put the lid on. I have a thick vinyl bag that I put the crank into and place on the bed lashed to the arm for storage.
The arm has lots of pin rash, the bed has plenty of wear from use, and the decals are nearly all silvered from years of cleaning, but it turns like butter and sews like a champ.
CD in Oklahoma