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I Forge Iron

O1 Tool steel for a blade. Questions

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OK, So I was unable to start my " Real Rail Roadspike " knfe project this weekend, unfortunately the weather and my forge both decided to play against me.

So I started doing more research on the process to use the O1, Annealing, heat treating and such to ensure I had a good understanding of the process, and I found something that created a question in my process. 

I notice a few different metal sites state to temper immediately after hardening, which considering I will be forging this in a Coal forge, I am very reluctant to do what with the better half having issues with me sticking dirty ugly scaly items in our normal stove to heat treat.  From what I gather the reasons for the immediate temper is due to the steel's brittleness. 

Can I Harden the steel, then take it to my belt grinder ( new purchase this weekend ) to clean it all up and make it pretty, and THEN temper it ?  To me that would make perfect sense, but Im a bit reluctant to harm my steel doing it the wrong way. 

Also, any recommendations on oil to quench with, since these will be mild steel / O1 blade bit knives, Ive seen peanut oil, motor oil and a few other items tossed around, but none of the steel mfg. sites list anything specific for O1 beyond " Oil "  and none of them mention quenching a blade/project that is of 2 metals.

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Can I Harden the steel, then take it to my belt grinder ( new purchase this weekend ) to clean it all up and make it pretty, and THEN temper it ?

​You could, but there would be risk involved. Also it would be easier to grind after temper.
I usually brighten a patch on the steel immediately after hardening, then draw it to pale straw in the flame over the forge. That way I'm pretty sure it won't crack by the time I get home to my oven. I have also considered having a pot of boiling water to keep hardened things in until I can get around to tempering, because of the freezing temperatures I work in.

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If you quench in vegetable oil then there is less SO problems than if you use nasty used motor oil "hey dear I want to stick this ugly piece covered in toxic stuff in the oven we cook in" vs "Hey dear this has been quenched in vegetable oil and I'm putting a tray under it incase it drips"


Long term get a little toaster oven and an oven thermometer for the shop.


I had a friend who did the hardening late at night and so put off the tempering for the next morning.  When he went to the work bench the next morningthe blade was in several pieces  just sitting on a rag.  You really want to temper as soon as possible! 


Now as to another method---get a deep fryer and fill with oil and with a cooking thermometer that will deal with the temps set it up to temper in the oil.  So quench in veg oil and pop it in fry oil and let temper, remove and cool and repeat as wished.  Doesn't work if you need tempering temps above the safe oil temps though.

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On a larger note, I've had the opportunity to get a few older ranges for free from people redoing kitchens. I friend of mine uses one in his shop to preheat/post heat treat welded items. Down side is usually space these take, but if you have the space, it might be well worth keeping in the back of your mind.

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funny you mention that DSW, as I was walking to the Gas station at lunch today, I saw a guy wheeling an old broken stove/range to the curb for pickup and thought to myself " Thats not a bad idea for Tempering... 

unfortunately it was gone before I left work, as Space is not something I lack of yet, I moved from a dinky 2 bedroom duplex into a large house with a 2 car garage, and only have 1 subcompact car to park in it, however I do expect that space to be taken up quite quickly between my newfound blacksmithing habit and my other " shop " projects fairly soon ( family has a history of drag racing and engine building, and robotics, My tax refund is being split between blade stock/equipment and controller boards/parts for the drone ive been designing ) 

And Steve, I didnt see that post initially when I looked, although I will admit I did not actually search for anything before I asked, however I have since read that post all the way through, and it did answer a lot of my " not quite answered " questions I did have.. 

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