I think the title says it all - how to make a strip of steel springy?

I beleive it involves heating and quencing it in water, but just how?

get a big pair of scissors!! :D

It has to spring steel. Ordinary steel is mild steel, which is general purpose.
Spring steel has a different carbon content, and is hardened and tempered to give the correct attributes.

And if i remember correctly (although it has been a while)
springs are around 45 HRC.

It has to spring steel. Ordinary steel is mild steel, which is general purpose.
Spring steel has a different carbon content, and is hardened and tempered to give the correct attributes.

This is the spring from an old primitive trigger mechanism from a device (scarificator) made around 1800. I don't think it's a replacement, just lost it.s springiness so i'm trying to restore it to working condition.

Gerron t'internet and see if there is anything on there :hihi:
If you heat it cherry red then quench it in water, that will harden it (if it is spring steel). But that make it very brittle. it then needs to be tempered, that is heated to a low temperature then quenched in oil.
This is usually done by whatching the oxide colour change as the temperature increases, then quenching at the required temp.
It might be easier to get a replacement spring. ;)

different steels have different cooling curves, that is the tempratures that are needed and the speed at which they need to be quenched in order to create the required mechanical state, what may make one steel soft may have a detrimental effect on another. As far as i can remember you'll need get the spring to it's original shape, then anneal it , then harden and temper it , but without knowing what steel it is, and unless you've got a furnace, accurate pyrometry, and tools it could prove to be a tall order.
How big is it?

You may be better off getting a replacement - to make metal springy it is hardened which can make it brittle. You may be able to get away with case hardening it though it may not last long before fracturing

case hardening is normaly reserved for blades, where a hard edge is required without making the body of the blade brittle.
As an appentice i spent many a long hour polishing case depth samples to a mirror finish, a particulary dull job if there ever was one.

How big is it?

It's small, about 2" long bent over into a U shape. I'll try heating it/cooling it as Artisan suggests - worth trying as a replacement would mean a lot of farting around to get one made

When you quench it, aggitate it in the fluid your using, otherwise you can end up with a steam or vapor jacket around the sping and you'll end up with an air quench.
Good luck

You might have a word with Geo Harrison of Harrison Springs, Rotherham. He is an extremely knowledgeable and helpful man who is a real expert. His company are a 'typical' s yorks / steel co., working away making springs for allsorts, from the space shuttle to F1 cars, nuclear power stations, vehicles and they also make tiny springs used by brain surgeons to clip little veins in the brains.

When M thatcher (washes mouth out) had her Jaguar bullet proofed it collapse the original springs. George Harrison solved the problem.

When M thatcher (washes mouth out) had her Jaguar bullet proofed it collapse the original springs. George Harrison solved the problem.

He should be bloody well ashamed of himself for that particular act of spite against the people of this country. :rolleyes: :gag: :loopy:

Ther's some info on heat treatment, with temperatures etc at this site http://www.westyorkssteel.com/spring_steel.html good luck