o1 tool steel

[kriegerj89]

Im looking for advice from people with experience with o1 tool steel. Ive never made a knife with it but I herd it works well. I've red books and articles on doing it but their all different. Steps that you do temperatures how many times you temper it and at what temperature. Just the basic procedure you do for this metal would be helpful.

[WBE]

Stock removal, or forged? If you do not have an oven or other source of temp controlled heat, you will be wasting your money and time. 01 cannot be HTed to it's potential by the simple methods used for the simpler steels such as 1080/84. If you have an oven, or other good heat control, it is relatively easy to HT.
STOCK REMOVAL

Stress relieve for one hour at 1200? to 1250?. Air cool. An optional first step, but reduces warp.

With decarb protection, pre-heat at 1250? for 30 to 45 minutes, then ramp up to between 1450? and 1475?. Let soak at temp for 15 to 20 minutes after heat levels off, and quench in Parks AAA or similar medium fast oil, heated to 130?. Point down in the quench reduces warp. Once in the quench, move blade fore and aft or up and down to cool faster.

Temper twice for two hours each, quenching in water after each temper. Best temper range is between 400? and 450?. Heating beyond 450? reduces edge retention ability with no appreciable gain in toughness.

[kriegerj89]

You like the point down quenching method instead of the edge quenching? And this might seem like a dumb question but what do you use to find the center line for where the edge is gonna be? Ive always just eyed it up.

[WBE]

When using precision ground steels, you can scribe a set of parallel lines down the edge about .015 to .020 apart. There are a few different ways to do this. A small version of a carpenters scribe works, or even a block of wood with a sharpened nail sticking out that you can bend to position. Color the edge with a felt tip marker. With blank and tool on a flat surface, pull the blade or the block down the edge, flip it over and repeat. Then grind a 45? angle along the edge leaving the .015 to .020 between your lines. You then grind the rest of the blade until the 45? angle is gone. If you are forging you pretty much have to eye the edge in. Edge in first or point down is your choice, but there will be less warp point in first. You can just edge quench if that is your choice. I like a full quench for maximum strength. There is really no wrong way with this, it just depends on what you think you want.

[kriegerj89]

That won't work with the thinness of my blade the line has to be about .052 from the edge theres no way I could make mark on something that fine with a 2x4

[WBE]

You make or buy a tool like this. The point is on one side of the marking tip. You twist the point to where you want it, and lock it with a set screw. You lay the flat blank, and the tool on a flat surface, and mark the parallel lines. The brass is 1/4" thick by maybe 1". The pointed shaft is 1/8". Set screw is 4-40 and comes in from the side.

[Ray Rogers]

Scribing a line .052 from the edge would be easy with a real scribe. The small one in the picture is the one I've used for 20 years, bought from one of the knife supply places. I think they run about $25 now. The larger one is one I built for scribing on large pieces of Kydex and Micarta. They're easy to make but it costs almost as much to make one as to buy it ...

[kriegerj89]

Ray there any places on line you know of getting one. Since this is my first time using one I think im better off getting one then making one

[WBE]

Check the knifemakers supply sites. One of them should have a suitable tool for that purpose. When I started, I would just sharpen the corner on the end of a file, until it would give me what I wanted. With Rays tool, it will mark the center even on a bent blank. My method requires the blank be near perfectly flat. There are advantages to either method, but I like to start with steel that is truly straight anyway. It lessens errors in geometry.

[Ray Rogers]

Try this: http://www.knifeandgun.com/ProductDe...oductCode=CTS1

[kriegerj89]

Thanks guys I appreciate the help ill have to order one hopefully it'll get here by time my steel does

[earthman]

Originally Posted by WBE

If you do not have an oven or other source of temp controlled heat, you will be wasting your money and time. 01 cannot be HTed to it's potential by the simple methods used for the simpler steels such as 1080/84.

How easy is it to HT that grade of steel then?

I thought that 01 was basically the easiest steel to HT, that's why most folk start off with it??

[Ray Rogers]

Most folks don't start off with O1, at least not by using the advice found on this forum. We generally recommend 1084 as the best steel to start with if you intend to do your own heat treating and 440C if you plan to send your blade out for heat treat.

To answer your question though, O1 is easy to heat treat providing you have an electric oven and can get the proper temperature control. Mostly, this means being able to soak the steel at precisely 1475 F for at least 15 minutes. Not non-magnetic, not 1450 - 1650 as your forge runs up and down but precisely 1475 F (or whatever temp works best with your equipment and process but it will be close to that). If you can't do that you'll still harden the steel, more or less, and most new makers won't be able to tell the difference. But, without that control you aren't likely to get a blade that would be significantly better than a 1084 blade but the cost of the steel will be much higher.

So, yes, O1 and 1084 are very close in the way the HT is done but 1084 is quick and easy and close enough is close enough for good results but O1 wants more control if you're to get what you paid for out of it ...

[kriegerj89]

I ordered a piece of 1084 from admiral it should be here this week since im in the same state. Ray could you give me advice on ht method for 1084 you know your stuff. Soak time temper time at what temperature edge dipping or point down and do you do the whole tang or just the blade? I'd appreciate it

[Doug Lester]

Easy to heat treat is relative and each alloy has it's own weaknesses and strengths. Jim Hrisoulas lists O1 as a good beginner steel with the exception that it not be used where flexibility is important. Others, like WBE, stated that it is difficult to heat treat with just a gas forge to it's fullest potential. Actually, they are saying the same thing but from a different point of view. O1 can be heat treated with a gas forge just not reliably to it's fullest potential.

From my point of view, though I'm little more than a well read beginner, steels with carbon levels above the mid eighties present their own problems with retained austinite. If you break down enough of the carbides in these steels and dissolve it into the austinite, when cooled, the carbon will physically prevent the austinite from converting back to a body centered structure and form retained austinite instead of martinsite. Some of the RA may convert to untempered martensite during the tempering cycles. One can get more to convert with cryogenic treatment. The best thing to do is not to create the problem by soaking the steel at under 1485? for an appropriate length of time and that requires a regulated heat source. Note also that this only applies to the simpler tool steel. Complex tool steels and stainless steels are an entirely different beast. There is also no way that you can look at the steel or test it in a non destructive manner to detect retained austinite and those tests that can are destructive and expensive.

The reason that beginners are steered towards simpler steel like 5160, 1070, 1080, or 1084 is that they do not contain enough carbon in them to have a problem with retained austinite to any great degree. If they form RA, they form so little that enough should convert during tempering to avoid problems or they are not capable of forming any appreciable amount of RA in the first place.

What it comes down to is knowing the alloy that you are using and staying within it characteristics.

Doug