Folder Springs

[Brent]

Worked all day on making a back spring for a folder and just can't get it. I used 1095 high carbon, heat treated and annealed. It broke at the back pin. Does anyone know a steel that makes a good spring with minimum heat treating to harden. Or, is there a steel that can be used without heat treating? I saw someone on the forum had purchased a bunch of springs. Does anyone know who it is, do they want to sell any? Does anyone know of a place that sells springs? Thanks for the help. Brent.

[jonet143]

is the spring for a custom made knife or to replace in a factory knife?

[Brent]

It is for a custom folder. I am using premade blades. Most of the blades are from 3" to 4". so i guess you can add a quarter to half inch for length to the pivot hole. this particular one is a three inch blade.thanks

[Hukk]

I use 1095 for backsprings. Tempering at 800 F (hold for 2 hours) after hardening (can be as much as 66RC) should bring the spring down to 45RC. 50 RC is about 700 F. Problem with these high temperatures is embrittlement. Quenching and tempering needs to be done immediately on 1095. On blades 400 to 450 F seems to be real common for tempering to about 60RC which is way to hard for springs.

Here is a good link from Admiral Steel http://www.admiralsteel.com/reference/heattrt.html

Normalizing 1095 3 times at 1570 F and air cool to touch helps with grain refinement and can help with embrittlement.

Using an oxy-aceylene torch to heat and cool the spring does work.

Or 0-1 is a good one, very forgiving and if it's not right the first time just re-do it.

God Luck!

[Brent]

thanks Hukk. I think i will try the 01 tool steel. I need something forgiving.

[Hukk]

6al4v titanium is a natural spring. Cut and shape it and it supposed to work well. The "chips" are fun while cutting - small little flare ups.