Bench grinder.

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warhead052
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Mon Jul 04, 2011 7:37 pm

Exactly. :D It makes it that much better.
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Crna Legija
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Mon Jul 04, 2011 10:52 pm

its most likely mild steel its useless for making a knife because you can grind out the shape and give it a edge but it will not be sharp for very long at all, the blade i made for the blistixs knife needs to be resharpened every time it hits wood.

mild steel has about 0.3ish% carbon it, where good knife steel should have about 1%+, if you wanna make a half decant knife that can take a hit you should look at getting a car leaf spring.
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inonickname
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Tue Jul 05, 2011 4:31 am

Crna is right, that metal will probably make a shitty knife. Don't bother with it. BTW, don't expect too great a result on your first try. It takes practice.

I've done a few knives. A leaf spring is a decent source of really hard metal. You'll need to heat it, forge it flat and then make your knife, then retemper, but it'll be very strong.

Here's a little Bowie I did from a leaf spring:
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jakethebeast
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Tue Jul 05, 2011 7:42 am

ummh, a word "steel" doesnt tell anything about it. for knifemaking, you need steel that has more carbon than normal steel. im not going to write here everything in know about steel, could write a book about it :D .

Steel i suggest to you is old file or leaf spring, those are easy to get cheaply and they harden pretty well. for hardening, i suggest differential heat treatment and long tempring in small heat, for tougher blade. and its not like "quench it in oil" its much more ;)

a bench grinder is a good when starting knifemaking, you can do prettymuch everything with it

edit, to crna: in most cases 1% is too much :D for though balde .6-.8 is great, for smaller "puukko" style knife .8-1.5, when the blade is laminated whit mild steel, the core could be 1-2.5%, but thats a bit different case :wink:
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warhead052
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Tue Jul 05, 2011 9:23 am

Well Crna, I am going to try, and if it doesn't work, then I will buy knife steel and try again.

inonickname, That top knife made me say holy sh*t.
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clemsonguy1125
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Tue Jul 05, 2011 11:44 am

Actually their are types of steel that can be quenched on in motor oil and some that can be quenched in water. But you must heat the knife to a certain temperature that makes it non magnetic to harden it. Then let it air cool. Repeat 3 times. Then quench, Then you must temper it.
That is all.
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ramses
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Wed Jul 06, 2011 9:52 am

Easy way to figure this out:

heat it up until it glows orange. Dip it in motor oil/ATF/some kind of oil. This will take care of the rust, too.

Polish a little section with sandpaper

SLOWLY heat the whole thing until the polished area starts to look blue-ish

Shove the part in wood ashes and let it cool slowly

try to file the bar. If the file skates, you can make a useful knife out of it. Otherwise, not so much.
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jakethebeast
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Wed Jul 06, 2011 11:58 am

ramses, no blue! the best with carbonsteels under 1.2% is more like the color of gold, thats about 200-250celsius. just put the blade in an oven to 200c for 1 hour and then 130c for 1.5hour. iv used lot of that with 0.8% steel and that gives a great hardness-toughness combination.

clemsonguy: every steel can be quenched in oil or water but when quenched in water the blade cools more rapidly and if the normalization prosess isnt just right the blade can snap or bend. i like to quech in motoroil-quenching oil mix, its like 1:3 mix.

The temperature color with carbon steels is light orange in mid light condition, thats just about 800-850c. right after the quens try to file it, if file doesnt "eat" the steel its hardened, othervise quench it again. other way to try it is to grind it, if you get more spraks than before quench, its hardened.

after tempering sharpen it, then try to beat some hard horn with it (like reindeer horn". if the blade doesnt take much damage at all, try cutting barss with it (like you do on wood) hope you understant this. if the blade doenst survive these test, heat treat it again.

iv treated and tested few hundred puukko-blades with these technigues and seems like this work the best. :wink:

EDIT: some typos :roll:
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warhead052
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Wed Jul 06, 2011 1:05 pm

I don't think you guys understand. All I have to do with it is sharpen the edge and its done...
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irisher
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Wed Jul 06, 2011 1:19 pm

No, not at all there is much more to knife making than that.
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warhead052
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Wed Jul 06, 2011 1:43 pm

Well I am going to try. I don't need a knife to carry around all the time, I just want to make one for the fun of it.


A little off topic, but irisher, I may be getting a full metal gas blow back uzi completely free. The down side is that the internals are broken, but the up side is that I can put my vortex cap in it! It even has a folding stock.
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ramses
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Wed Jul 06, 2011 2:19 pm

warhead052 wrote:I don't think you guys understand. All I have to do with it is sharpen the edge and its done...
So a file skates across it?


As to the blue, that was a preliminary guess based on my plans for some 4340 for another purpose.
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Wed Jul 06, 2011 3:08 pm

Here don't say I never did anything for ya! :P :wink:
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jrrdw
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Wed Jul 06, 2011 3:47 pm

But on a serious note you should Google "grinding stone dressing", something every beginning machine operator should know. Knowing how to clean and dress a grinding stone will make your work go easier with less wear and tear on your grinder and you. With the grinder you got you will need to be easy on it if you want it to last.
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