Michael Black wrote:
snip

Even my Sears "rotary tool" is at least 15 years old, and I wouldn't call
it "elderly".

I have one of those. I got it used at least 17-18 years ago. At that
time it had done hard service in a luthier's shop and needed work on the
speed control and new brushes. Sears had a hard time coming up with a
diagram, but finally was able to order parts for me.

jak

Michael