Need heat treat info.

W

Wanderer70

Joined
Nov 21, 2006
Messages
14
As I mentioned in an earlier post, I am 71 yrs old and want to make knives again. I will be using A-2 and O-1. The A-2 I will send to Paul Bos, but the O-1 I want to heat treat my self. Anyone know of a good book I could get with info on heattreating O-1? Or, if you have any personal experience you could share I would be grateful. Thanks, Keith
 
Search amazon.com for books.

O1 means Oil Hardening, and i think tops out at 56rc. Quench in motor oil/whatever and temper. Done. (details omitted due to ignorance :P)
 
You can bring 01 up to a red-orange and quench in ATF, then temper in your kitchen range at 425o, and have a usable blade. BUT, if you want it right, it needs to soak about 20 minutes at 1200o, to 1250o, for 20 minutes, then be brought up to 1475o, to 1500o, then soak at that temp another 20 minutes. Then be quenched in the proper oil. Then tempered with 2 cycles, 2 hours each. 01 has a good amount of chrome, and other alloys, and you will not get the best solution, without a preheat, and a soak. To get the best from 01, you will need a controlled heat source, and decarb protection. It is not the simple steel that some believe it to be.
 
The book on HT is called "The Heat Treaters Guide, Practices and Procedures for Irons and Steels". It is put out by the ASM. Pricy, but worth every penny.
Stacy
 
O1 is an excellent fine grained steel and takes a great edge at high hardness. Makes very good hard knives. Makes good gauges and tooling too, if you'll tolerate the oil quench (most folks don't bother and consider O1 a "buggy whip" in machine shops). Rusts pretty badly.

Listen to LRB. O1 is not the simplest steel to HT well. While it tops out around 65 (not 56) is can appear hard to a file while still being largely soft and weak because your elements take time at temp to diffuse into solution. Hitting your temp isn't enough, you have to park it there for a while, meaning you need a furnace to do O1 well.

I'm not so sure about a three step preheat, but it can't cause any harm either, as described. I just go directly to austenitizing temp for thin stuff like knives, but perhaps I've been doing it wrong all these years...

Consider 1084, it goes into solution quickly, requiring no soak, but it needs a rapid quench.
 
As a curiosity, and not to steal a thread, how would you go about heat treating A2? I've considered adding this to my steel list as a blade steel. I hear it's as good and maybe even better for blades than O1 with a slightly higher stain resistance. Any truth there?

I've got an oven, quench plates, and stainless foil. Just looking for time and temp. Also considering HT of 154CM.

Thanks!

--nathan
 
Pre-heat at 1455F. Austenitize at 1750-1800F with a 20 minute soak.Air cool or use quench plates (cool to room temp).Do two ,two hour tempers at 375-400F for maximum strength and toughness.

A-2 benefits from cryo. Cool to room temperature. Do a snap temper at 300F for 30 minutes. Cool to room temperature and put in dry ice or LN for one hour. Temper immediately.
Stacy
 
I do O1 myself and have had good results, the good news is that it will harden at a relatively low temp 1500 f which is pretty easy to achieve. To hold at temp I suggest some type of forge, one brick. I bought several firebricks for kilns and stack them to make a forge/kiln and heat with a good propane torch. I use a atf/oil mix for quench at 125 F. I have done differential quench with some sucess but not as good as 1095 or 1084. I got alot of O1 cheap and that is why I use O1 rather than 1095 or 1084, all are good steels but because of the hold time the decarb can be significant. I grind my blades to about 1/3 complete prior to heat treat. That is if the steel is .25 thick I will grind the edge to 0.08 to leave enough steel to remove the decarb when I grind down to 0.02 to 0.03.

I do folder A2 blades in my kiln but send large to Paul Bos, they turn out great.
 
You must log in or register to reply here.
Back
Top