Making springs

[bombdoc]

The old UK gunsmith's technique for tempering springs was "burning off".. Having hardened the spring in tempering oil, the spring was then heated up again to the point where the oil coating the spring would remain burning. The burning spring was then left to burn out, and then tested.

Traditionally sperm oil was used to temper springs, however cooking oil seems to do the same job.. and leaves the workshop smelling like a greasy spoon cafe!

That said, I tend to rely more on one of those IR thermometers these days

By the way.. I find one of these really useful for making coil springs...

Hemingway Kits Universal Spring Winder