Does he have any idea of what he wants for it? The South Bend lathe is a
good lathe and if it's something like $600 or so, I'd get it even with flat
belts. The only requirement is that it be able to turn threads.
A flat belt lathe will probably have babbit or sintered bronze bearings in
the headstock and that needs to be checked to make sure that they are in
good condition otherwise you will be looking at a repair in that area.

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Why do penguins walk so far to get to their nesting grounds?