High carbon steel sources

Cold rolled 1018 seems tougher than annealed 4140.

I like bladecrafting but have only done some stock removal at this point, I am working on plans for a forge. I don't see the point in throwing a knife, but I see the point in throwing a throwing knife.

A dedicated thrower is a working tool, a range of steel will suffice including medium carbon steels. Why is a 1018 thrower inferior to a 1060 if they both work and neither bend?
 
I believe 4140 is high impact steel. One application of 4140 is in the making of hammers. I have a bunch of 4140. One time I forged out a small blade from it, heat treated it and put it in a medum sized vise and hit it cross ways with a sledge hammer. Busted the vise right off its base. Doh!

Cold rolled 1018 could be a little "work hardened" from the process of being cold rolled. I have made throwers from it. They all bent over time just as the un heat treated 4140 did. That is just my experience. Again, to be a knife, be it a throwing knife or a butcher knife, a piece of steel must be heat treated to be a knife. Otherwise it is just a knife shaped object.

There are exceptions to every rule. Ed Fowler tells a story about an old knifemaker who use to make a good edge holding butcher knife out of mild steel he cut from car fenders. His method was to cold forge the thin steel, effectively work hardening it enough to "hold" an edge in the range that is acceptable for kitchen cutlery and a little behond what is available in production knives of the same catagory. So making a "knife" from non or low carbon steels is possible, it still involves some manipulation.

The home hobby guy can make a far superior knife to the inexpensive production knives with just a little study on the subject. He can afford to put in the time and effort into quality that the high volume companies cannot afford to and still compete in the market with the low prices they charge.

Thanks for suffering thru my ramblings. Corrections or opposing views are always welcome.:D
 
The next to last knife (not a throwing knife) I made was from an old file. I used a Mapp gas torch to soften the base to drill holes for the handle, and left the rest as is. Tested at a Rockwell C Scale hardness of 64. Anyone who tries this be warned, you could be looking at a long time at the grinder, depending on your method, and how picky you are about the final appearance. Most of the time is spent waiting for it to cool, and making sure you dont overheat the steel when grinding. A wet grinder would be the best bet I suppose. I also made a throwing knife from steel from Home Depot,
3/16" thick by 1" wide by 14" long. It didnt stay around long enough to bend. I lost it within a week of making it.
 
me2, you could speed up that wait time by keeping a cup of water next to the grinder and dip the blade when it starts to get too warm.
 
I do want to ask, though it is rather off topic, do you (Ellis) consider ceramic and obsidian cutting implements to be knives? Or what of the Andean copper based alloy tumis and chinese bronze swords, knives and spears that rival some steels in their hardness and cutting ability? Or perhaps bone implements that have been called knives as well. Do you consider these all to be knive like objects?

I confess though I am inspired by your take on heat treating, I do not think a knife must be made of steel.
 
Not to start a shop talk thread in throwing forum, but to continue discussion. I had a bucket handy, but my grinder doesnt like water too much, so it was grind 1-2 passes, dunk, dry, repeat. Even then I turned the tip blue and had to grind it off and start over about 3 times. Be aware this was a $40 grinder, so it may have been just as slow on the 1018, but I didnt have to grind off nearly as much.
 
Yes Bambooleaf, I agree with you. There are exceptions to every rule. One can always paint himself into a corner when trying to talk in absolutes. All your examples are good ones. At one time each one was the hight of technology. But one could counter argue that flint and chert benifit from heat treatment and were heat treated in their time periods with a sort of annealing process that makes it easier to work. Copper bronze and brass work in the opposite way that carbon steel does. Hammering work hardens it. To soften it to prevent it from cracking from over working you heat it to cherry red, then quench it. The hammering of the bronze is what transformed them into a usable spearpoint or sword. Bone can be hardened by slow roasting near a fire and even wooden tip spears were hardened in the fire. Obsidian may be as close to an out the box material as you could get, but even it was heat treated in nature by being melted and slow cooled as to retain its ideal properties.

The point I was trying to make, altho perhaps poorly, is that it is the heat treatment that makes a knife, a knife.

Lets use a file as an example.

The difference between a file and a knife is in the heat treatment. To make a file, you take a bar of 1095. Cut the teeth into it, heat to critical and quench. This makes a very good file with a rockwell hardness of 62-65. Keep that file cool and grind an edge on it put on a handle. It looks like a knife, but is actually a very poor one and close to useless. It is almost immpossible to sharpen and is very brittle. Any amount of flex and it will break like a piece of glass.Chopping with it will chip out the edge. Because this file has been made into the shape of a knife, does that mean it is a knife? I really don't think so. Altho the shape and look is there, it fails at the tasks we call on a knife to do.

Now if you take another piece of 1095,or even that file, grind it to the shape of a knife, heat it to critical, quench, then put it in the oven and draw the hardness back to 58-60 rockwell and put on a handle. Now we can sharpen it easily. It is hard, but not too hard. We can chop and flex the knife without fear of it breaking or chipping out on the edge. It performs all the tasks we call on a knife to do. It is now a knife.

I don't think it is unreasonable for me to want my throwing knife to perform with the qualities I feel are important in a throwing knife.

1. It won't break easily.
2. It won't bend easily
3. It will hold its tip well, but not chip out.

This ideal is easily achieved by my choice of steel and method of heat treatment. I can choose either to learn to do it myself, or buy one from someone that understands the qualities needed, and how to bring them out and make a piece of steel into a knife.:D
 
FWIW, I chiseled the Rc 64 file knife through a piece of cherry wood with a claw hammer. Just some deformation on the spine. It also took 3 blows with the claw hammer to break off the pieces while cutting the tip. I cut about 90% through with a dremel cut off wheel, then gave it a few whacks.
 
Ha Ha, there goes another exception to the rule. "File shaped objects" Cheap files are not made from tool steel, but are case hardened mild steel.
 
The hardness tests were taken after the teeth were ground off, though I probably softened it a little while grinding, even though it didnt turn color in any area left in place.
 
With a case hardened file the inside could be soft enough to bend and the outside could give a high rockwell reading. Some chinese swords have claycoats with carbon sources in them so that in differential hardening some case hardening also occurs. Would a tool steel file break or bend once it reaches a high enough stress point? i guess that depends on heat treatment but I have only researched it, I have not experimented with it.
 
I suppose its possible that the core is not hardened, but my cutting tests dont seem to show it. The brand of the file was not legible, so heaven only knows. At any rate, its not a throwing knife, and so doesnt deserve further discussion here.

To the orginal discussion, Admiral Steel sells steels down to 1070 and 5160. The latter would be best I would think, although 4140 would surely work if you can find someone to sell small pieces instead of large runs.
 
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