blade hardening

[Soloman]

Ive been given some toolsteel flatbar ( thanks warthog 1981) with the intention of cutting out a knife blank or two.
Does anyone know someone who can heat treat it after i do this.
Could i do this mself using a coal fire,if so how.
thanks Soloman.

 

[Matt.S]

To harden tool steel:
1) heat above the eutectic point ('critical temperature') -- usually a cherry red, c.800 degrees C
2) quench in oil, water or air depending on what the steel is. (Do you know exactly what type it is?)
3) clean the blade and gently heat to the tempering temperature, then quench again. Alternatively use an oven (using a separate oven thermometer for accuracy).

Coal will certainly work -- it's what many smiths use, albeit with a forced air draft. You will need to have something to hand (tongs, pliers) to pick the steel out of the fire with. Charcoal or wood will work just as well though.

If you have a large gas torch, that will probably work too.

 

[Soloman]

Thanks matt,the markinge are ansi 01 c.90 mn 1.30 cr.50 w.50 v.20.
Itake it thats it make up.

 

[stanley lake]

Hi would you be using your coal fire in doors if so i would would air on the side off caution if using oil to harden your blade after heating in doors as it tends to boil up in to flames when quenching the blade you could end up burning your home down salted water brine is a good substitute. also a good tip is to use a magnet when heating your blade up as the steel loses its magnatisam when it reaches it critical point keep tasting the blade with magnet as soon as the magnet stop sticking to steel no later or you will go past the critical point place the blade in to your qenching fluid vertically tip first easy

Stanley

 

[Matt.S]

Thanks matt,the markinge are ansi 01 c.90 mn 1.30 cr.50 w.50 v.20.
Itake it thats it make up.

O1 is a common grade of tool steel, the rest (as you surmised) is its makeup -- 0.9% carbon, 1.3% manganese, 0.5% chromium, 0.5% tungsten, 0.2% vanadium (balance is assumed to be iron and trace amounts of sulfur, silicon etc.) O1 is commonly available in most industrialised nations in a variety of stock shapes and sizes. It's a high-carbon low-alloy steel designed to be oil-quenched and having good dimensional stability.

In English, that means it's meant to be quenched in oil. Probably best you use veggie oil, since used motor oil has some nasty carcinogens in the smoke. Make sure you use a metal can to hold the oil and have a metal lid handy incase it flares up. Here's a great link with more detail than you need: http://www.threeplanes.net/toolsteel.html

O1 knives are often tempered to around a straw colour, which equates to roughly Rockwell 60C. Some people will want a harder blade, some a softer one. Your choice.

 

[stuart m]

Or, unless you specifically want to do it yourself, for the experience, drop me a line when you are ready, I'll have a look at that for you, just cover the post cost

 

[robin wood]

Or, unless you specifically want to do it yourself, for the experience, drop me a line when you are ready, I'll have a look at that for you, just cover the post cost

Now that is a very generous offer, and Soloman if Stuart gets it done for you it will be done well.

I was downstairs from you yesterday Stu visiting Andy but by the time I was done you were gone.

 

[Gwhtbushcraft]

Here is a sight i found helpful:
http://www.threeplanes.net/toolsteel.html
George

 

[stuart m]

Now that is a very generous offer, and Soloman if Stuart gets it done for you it will be done well.

I was downstairs from you yesterday Stu visiting Andy but by the time I was done you were gone.

That's a shame mate.... As it happens, if Soloman decides to take up my offer, it'll be Andys' furnaces I'll be using to do the job...

 

[Nagual]

Hi would you be using your coal fire in doors if so i would would air on the side off caution if using oil to harden your blade after heating in doors as it tends to boil up in to flames when quenching the blade you could end up burning your home down salted water brine is a good substitute. also a good tip is to use a magnet when heating your blade up as the steel loses its magnatisam when it reaches it critical point keep tasting the blade with magnet as soon as the magnet stop sticking to steel no later or you will go past the critical point place the blade in to your qenching fluid vertically tip first easy

Stanley

Ouch! So does it taste of cherry, as well as look cherry red?


Nag.

 

[Soloman]

Many thanks Stuart for that offer ill take you up on it if i may.
Ill drop you a line when ive a blade worthy of your attention.
Again thanks.
Soloman.

 

[stuart m]

Ouch! So does it taste of cherry, as well as look cherry red?

Nope, tastes like chicken.....

Many thanks Stuart for that offer ill take you up on it if i may.
Ill drop you a line when ive a blade worthy of your attention.
Again thanks.
Soloman.

No worries, speak soon...