spring heat treating

[bob levine]

who can tell me the proper heat treating and tempering for a flat spring made of O-1 tool steel. im a knifemaker that has been given a project. Levineknives@msn.com

[Imakethings]

high red/low orange, oil quench to harden, temper to dark blue.

That's the oversimplification without the detail behind it, I highly suggest doing a lot more research and reading, the above method will get you a 1/2 decent hardening and temper, but it could be a lot better if you know what you're doing and have adequate temperature controls.

[bob levine]

I do know what i'm doing thank you. I have been making knives for over 35 years and am a member in good standing of both the knifemakers guild and the German D.M.G. (Deutche Messermacher Guilde) Thats the German knifemakers guild. I just dont have any occasion to make springs.

[Imakethings]

Wasn't terribly sure of your level of experience and wanted to cover my bases. I do apologize if I've offended.

You want to temper it at about 400C for an hour to get the hardness you want, it will probably harden up to about 50-52RC

See: http://www.alphaknifesupply.com/Pict...-DS-Bohler.pdf
For cooling curve and specific technical information on the steel.

[WBE]

It is widely accepted that most springs need to be at the low to upper 40's in Rockwell hardness. To reach that with 01 I believe you will need to go into the 800? + range. I would suggest that you google up a hardness vs temp chart for 01, that can be reasonably trusted, and see what you find, then run a test spring to see how well it works for you. The 10xx spring steels make very good reliable springs tempered from 725? to 750?, but 01 is a different animal when used as a spring. It makes a very good spring, but requires a higher temper heat.

[Bob Hatfield]

I used to do gunsmithing and have made several "V" springs for shotguns. this is the methold I used. It is the way some of the old English gun makers made springs.

shape & grind your spring into the shape you want. You will have to heat it to red to bend it to the shape you want. Then Heat to full red about 1500 degrees and quench.
To temper submerge the spring in a pot of melted lead, which will be about 650-700 degrees and hold until heated though, one minute for most gun springs and remove and let cool covered in lime powder. clean up spring and test to make sure it will not break. The "V" springs I made with this methold are still in use after 15-17 years in the shotguns I put them in.

If you are making flat or V springs. Be sure not to leave any grind marks across the spring as this will be a weak fracture point that may break in time. Try to do your grinding lenght wise if possible.

[WBE]

I repeat. 01 requires more temper heat when used for springs than simple 10xx steel types.

[Bob Hatfield]

I have to agree with WBE as I purchased my spring stock from a gunsmith supplier and I believe it was one of the 10xx steels that tempered around 700 degrees for a hardnes of around 43rc. One of the problems of getting old, forgetting things.

[bob levine]

thank you all for the great information . Now who has some info on making a spring of D-2. i know the hardening temp and duration. I need the F temp and duration for turnig it into a spring. I should never have started on the project. Oh well