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Metal for blades and hardening techniques Answered

hey y'all!  need some 2 cents on another instructable... 

so, i recently posted an instructable on how to make your own machete, and i have received some feedback on using tool steel, and quenching the metal before final sharpening to keep an edge longer.  

does anyone have any expertise on what type of steel/metal i should get, where i could get it, and how i could go about quenching the metal?

any help would be much appreciated!



7 years ago

O1 tool steel is a very good material for knife making and is fairly easy to acquire. Most lathe knives and planer blades are made from O1. It can be purchased online from Fastenal in various dimensions.

To heat treat O1, bring the steel to it's critical temperature of approximately 1370 degrees F. This is the temperature at which the metal ceases to be attracted to a magnet. Forging is best done above 1500 degrees F if you plan to do so. Once you have heated to steel to it's proper temperature, quench it in oil. There are may oils that will work and there are many opinions as to which is best. Many bladesmiths mix there own concoctions from transmission fluid, cooking oil, hydraulic fluid or others. Used peanut oil from a turkey fryer will even work. Take the blade from the forge or heat source and quench it in the oil. Then remove it from the quenching liquid let it cool to room temperature or "normalize". At this point the steel is very hard and brittle. You will now have to "temper" it to make a reliable blade. Do this by placing the blade edge up in an oven preheated to 500 degrees F for one hour. This process of heat treating, if done properly, should bring the hardness of the blade to about a 58-60 Rockwell. This is about where you want the hardness. It is a balance between hard and flexible that will take and keep an edge.

Please note that you will want to do about 95% of your shaping and any hole drilling before you heat treat. Otherwise, it will be much harder to grind and drill. Also, the process of heating will leave a dark scale on the blade. You should remove as much of this as possible by sanding before you place it in the tempering oven. After one hour in the oven, remove the blade and again let it normalize. Once it is cool you can begin the final sanding, sharpening, and handle attachment.

This is a very brief narrative but I hope it helps. There is a wealth of information available online and even at the public library.


7 years ago

I would suggest you message (or leave a comment) for Mrballeng. He's done some amazing Instructables here using metal, and I found the information he posted on this Instructable (in the comment section), to be really helpful for coloring steel with the use of heat. I can't say for sure, but I'd bet he has a wealth of information on how to strengthen the steel you are using to create a stronger edge.

So I guess that qualifies as my 2 cents?


Reply 7 years ago

great! thank you very much! i will be sure to shoot him a message.