let me know...

[David Yukon]

I want to know if I got this right, I have a knife blade from a file, ready for "heat treating" ... So bring the steel to cherry red(bright or dull?), dunk into oil(canola??)  until cool... put in the oven at...F for....? I think it is 420F for an hour and let cool...

Is that it?? I made a one before but don't remember the details.

I have MAP torch and a regular kitchen oven.

P.S. it is not a hunting blade, but still a blade and if it work, I try something bigger.

[Wingless Arrow]

Ok, well i'm not an expert at all. its not necessary to quench in oil, water works too, but oil is used to harden the blade. which allows it to hold an edge better, but it does make the blade more brittle. but its definitely not canola oil. its motor oil, but be careful cause it will probably catch on fire. not sure about any of the rest, sorry. hope it works out.

[Steve Nuckels]

David, heat until a maganet will not stick the pplace in heated oil 110-120 deg.  when cool brighten the blade up with sand paper/grinder and temper for 1 hour at least two times should have a straw color!

Steve
---------
Potomac Forge
ABS Apprentice

[LONGBOWKID]

Hate to contradict, but I would most definetely shy away from a water quench on unknown steel. Oil is a much safer option. Also, canola oil is just fine to use, but as said it will flame up for a second, so beware of that.

Heat the steel to non-magnetic,(usually a dull red in daylight or bright red at night, but you really need to be sure that it has reached critical temp.) then quench in oil, carefully wipe off as much oil as you can (to prevent stinking the house up with burning oil) then go immidiately to the oven for two, one hour temper cycles at around 425-450. Then proceed with the cleanup and handle. If you neglect to go immidiately to the temper cycles you risk causing stress cracks in the steel, and if you try to work with the blade (sand or grind) there is a strong possibility you will break it. Been there and done that, its no fun when you are first starting out and break a blade, but it was a sure enough learning experience.

Another tip, as it is cold this time of year, be sure to heat the oil up a bit. (80-100 degrees at an estimate) If you quench into 20-40 degree oil it can cause the blade to warp or crack.

Good luck!

Brandon

[Wingless Arrow]

No dont worry about it longbow. i tried to make it a point that i dont know much about it. just tryin to help out with what i have read/thought. im still trying to learn whats what about knife making. thank you for settin it straight.

[David Yukon]

Thank you guys all info is good!!!
I will try that tonight!!

[David Yukon]

Ok, went to the oven for an hour at 425F, and the blade turn out with a lot of purpuly shade with the straw colored ticker part, so is purple ok, I doubt it....

[David Yukon]

Pulled out the blade after the second cycle in the oven and... I guess I screwed up... the blade came out blue...A nice blue, but far from the straw colored it was supposed to be!! Maybe I had the wrong file(no name). Maybe I will ask my friend who make knifes to sale me a piece of O1.... And restart...

[Ragnarok Forge]

David,

I would like to clear a few things up for you.  

File steel is normally 1095 or W2 if it is a good american file.  You want to heat the blade to nonmagnetic and a bit past it to 1475 degrees.   With high carbon steels it works best if you can hold it there for 5 minutes.  This is not possible with a torch.  Once you hit temp quench the blade.

Do not use motor oil as a quench for high carbon steels it is too slow.  Do not use water unless you want to meet the tink fairy.   Use Canola Oil heated to 125 degrees.  No more than 5 degrees above or below that for optimum results.  Use a candy thermometer to check your oil temp.

When you quench the blade plunge it full depth into the oil.  Put it in straight.  Do not move it side to side in the quench.  Keep the blade in the quench until it reaches around 400 degrees, wipe clean and place in the oven at 400.  Leave it in the oven for two hours.   Pull out and let cool to air temp.  Put it back in the oven at 425 for 2 hours.  Repeat one more time.

You are getting darker colors due to higher heat in the oven.  This can be caused by putting the blade to close to the heating elements or a stove that reads wrong.  Put the blade in the middle of the oven and use a steel oven thermometer to check your temps.

The blade can be re-heat treated.  Heat it up to nonmagnetic and cool it to room temp in the air.  Repeat this two more times.  After the third cycle, heat it to just past nonmagnetic and quench it in the 125 degree Canola, then temper in the oven.

A full proper heat treat for the steel you are using is beyond the equipment you have.  The method posted will get you a well hardened blade that will make a good knife.

I would strongly reccomend that you use 1080 or 1084 for your next efforts on knife making.  Another option would be to have your buddy help you with the heat treatment of your next few blades.

[David Yukon]

Thank you very much, I made a crooked knife a few years back and it turned out great... Guess I got lucky... I will talk to my friend and see what I can do... I hate to borrow equipment... Anyway, thank you for your help!
Cheers

[gudspelr]

David-

Clay has some great info there.  If you are otherwise happy with your knife, minus the heat treat, I say give it a try again.  Those 3 cycles of heating it and then air cooling will let everything "relax" a bit from the last process.  Then, go back for the quench and you just might end up with a great knife.

Those colors you saw are a great example of what happens when tempering-it just ended up too hot in the oven and softened past the point you wanted.  Don't get too frustrated with it, this is how we learn   .  Good luck and post some pictures.


Jeremy

[David Yukon]

Thank you Jeremy! I will certainly try again, but like I said, I have a friend that make knife for a "living" and I'm sure he can help and show me a few things... I will try talking him into teaching me the basics... We"ll see. I will show you guys when I have some thing!!
Thank you again.