why the variables?

V

vaquero57

Joined
Nov 12, 2000
Messages
131
I bought a bar of 0-1 from jantz several months ago and it said temper at 400 degrees for approx. 58 rockwell. I bought another bar of 0-1 from a steel company in Omaha and on it's package it said temper at 500 degrees for 58- 60 rockwell. 2 bars of precision ground only difference was 1 was 3/16 and 1 was 1/8. On a known knife site of a well known maker it says temper 0-1 at 350 for about the same rockwell. Ok what is going on. The first bar I followed its instructions and this current bar I have been doing 500. How in the hell can there be so many different opinions on this. Fact should be fact. Especially with 2 bars of 0-1 with different manufactures instructions. I know some of you are gonna tell me your opinions on tempering temp but can anyone tell me the correct temp. and most importantly why is there not a standard for this steel?

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" I am a shootist."
Clay Allison
" Does this mean we are bladists?"
Vaquero57
McAlpin Bladesmithing
 
You will get better opinions then mine on this one, but I will tell you that I like to temper at the lower temps in a range of temps for a given steel primarily because I prefer to maintain hardness for good edge holding. In addition, I have found that my kithchen oven varies from 40 degrees above the set temp to 40 degrees below the set temp as the element cycles on and off. I teper O-1 at 375 to 400 depending on how my file bites into the steel after quenching.
 
tell u what , vaquero...i use O-1 almost extensivly and i`ve been tempering in a old toaster oven , the temp only varies about 5 degrees , i temper at 350 for an hour then let cool in the toaster oven , then do it again for an hour and when i`m done they come out at 59 to 60 Rockwell every time!!hope it helps you a bit
smile.gif


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i keep grinding and grinding and it is still too short!!
 
Welcome to metallurgy and heat treating! I hope you didn't think this was going to be easy...
01, like most steels, can even vary in composition from mill to mill, and, can vary from batch to batch within a mill!!

When you buy a mill run, you get the specific chemistry and metallurgical data FOR THAT RUN. If you're a good customer, you can even get the composition tweaked to your specific needs, i.e carbon content a few percent higher, etc.

On some steels, you'll see a range of carbon-for example, the no-name may say 1.00-1.05%.
Pay more, and, you'll usually get tighter ranges on alloying percentages. check STARRET vs. "MADE IN USA" specs in an MSC catalog, for example. Starret costs more, but, alloying is more precise.

Certainly, tempering and the entire heat treat response is directly related to composition (and, other things, as well, as if this wasn't complicated enough!)

So, when one wrapper says 400 and the other 500, or whatever, if you're lucky, the steel in that wrapper will respond as stated with that cycle.

Best bet is to have the hardness of your blade checked by a machine shop or met lab using a Rockwell Tester. When you get what you want, stick with that brand of steel.

RJ Martin
 
It can be even more complicated than Randal just said. Slight variations in the chemistry of the steel, variations in the quench rate and the section thickness, and most important to O-1, variations in the austenitizing temperature and the soak time. That last one (time and temp) will affect how hard the piece is "as-quenched" which will also affect the way it responds to tempering, thus the differences of opinion on the hardness at different tempering temperatures.

By the way Vaquero 57, I am in Iowa, and started out very low budget in the knife business 15 years ago. If you wanted to come and visit sometime I would be happy to try to help as much as I can. Not many of us in the cornpatch, we need to stick together. (I was a mechanic to start out with also).

Contact information for me can be found at my site http://www.mvforge.com
 
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