Thank you, manicmike in Melbourne! That does make sense, and I had wondered if Connie's statement was too broad. If someone tried to sew for very long using the fast controller, it's not surprising such a problem would develop. Just about everything needed to be adjusted, tightened, etc.
Now the trick will be to find someone who can make sense of this machine and keep it from being melted down.....it does seem solidly made and worth preserving.
Dianne in Colorado