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spring steel


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I use smaller spring steel for stems and braids and such and it works just fine...as long as you don't quench it. If it's left to cool at a normal rate it won't get brittle. I did the exact same thing the first time I tried to braid with it. I don't, however, know if reheating a piece that's been quenched and then cooling slowly will fix a brittle piece of steel.

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If it is spring steel (and it sounds like it) then you should forge it at a slightly lower temperature than mild steel. Orange yellow and down from there to cherry red. Some of the really old books say cherry red as a starting point for spring and tool steel but one things for sure. Quenching spring steel in water from non magnetic will make it hard and brittle. You'd need to temper it to take out the brittleness, if it hasn't already cracked. You'll find how to do that by searching the site. BTW some carbon steels are air hardening so even if you dont quench at all they will still harden. What you need to do is forge it then anneal it. Find either a bucket or vessell big enough to hold all of the piece and fill it with wood ash (or you can use vermiculite and pearlite, often used in kitty litter). Heat the steel to non magnetic and then cover it with the wood ash. It acts as an insulator and lets the piece cool very slowly, without all the science what this means is that it doesn't get hard or brittle. There's a whole raft of detailed info about what happens to steels as they are heated and the chemistry involved right here on this site. Dig around.

Edited by Ian
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Air cooled is as hard as you'd want to get it. I made an antique door handle last year for our bunk house - just grabbed a piece of steel with a comfortable cross section, but it sounds about like what you have. I don't know if it was spring steel or just high carbon, but I finished, air cooled to well below black, cooled the rest of the way with water and started to drill some mounting holes. After trashing a drill bit, I annealed it in wood ashes and all is well.

My first attempts to make tools from known spring steel resulted in breakage when I used either oil or water to quench from non magnetic.

In some former University work I did lectures about heat effects and welding on high pressure oil field tubulars. I kept a leaf spring in the classroom that had been heated and quenched on one end, annealed on the other and untouched in the middle. I would flex it first to show students that it was truly a spring, then use a hammer and anvil to cold bend the annealed end and to break pieces off the quenched end. Clearly this was a single piece of steel with vastly different properties, depending only on the heat treatment.

The point I was making was that the lower grades (55,000 psi) could be field welded, the 80,000 psi intermediate grades required an expert and some controllable conditions, like not out in a cold wind, and the 110,000 psi stuff was not suitable for field welding, period.

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There is heat treating information posted as sticky's in the knife section, as that the most common area of metal work needing thermal treatments, but its not the only one.

To get the most from a spring, you do quench, but also proper tempering is required to remove the brittleness, but most people do not understand controlled heat treating outside of the Knife and auto industry's.

Edited by steve sells
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