John Hofstad-Parkhill wrote:

A good friend of mine is rebuilding a 1913 Overland. He's run into a
problem with a bronze spring. It was part of an assembly that included a
shaft and cast iron wing nut. He used heat to tackle the frozen wing nut
and has annealed part of the spring.

He's wondering on how to harden/temper it back.

Copper alloys, such as bronze, can only be hardened by work-hardening.
Thus, I expect some sort of re-forming of the spring will be required,
but I don't know how you'd replicate what was done in the factory
without knowing what they did (in terms of the state of the bronze) to
form it in the first place. That is, I don't know how you'd figre what
state (half-hard, say) the spring was in before the final forming to
it's final shape. Hopefully it's not too critical, or someone has the
details available.

--
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