Crap on my knife blade

the4th

the4th

Joined
Mar 20, 1999
Messages
1,163
Couple of hours roughing out my knife blade blank.
Many more hours sanding it to about a 400 grit finish.
Ground the blade profile with my new belt sander / flesh removing machine (which, by the way, nearly ruined my knife several times).
Spent a little more time re-sanding to about a 200 grit finish.
At this point it looked like you could carry it and sharpen it.
Then built a big charcoal fire and started to heat treat the blade.
Got the blade to non-magnetic (tested with a hard drive magnet (if it won't stick to a hard drive magnet, it ain't magnetic).
Quenched in 130 degree olive oil / cooking oil mix.
Reheated the blade to non magnetic and quenched 2 more times.
So far have only drawn the knife once in the oven for about 2.5 hours at 350.

I started to sand it back down again before the final 2 drawings and have noticed a really weird blotchy pattern all over the blade. It looks terrible. This isn't just scale on the blade, the steel looks as if it melted in areas.

Is this a normal thing when working with charcoal furnaces? How can I combat it without having to buy a gas furnace?

Now it's off to find some 80 grit and a sanding block.
 
What kind of steel are you using ? I was having this trouble with some 1095 and my coal forge.I found out that if you have oil or coal dust on the blade it will do this,my problem quit when I started cleaning the blades before heat treating.The only other problem that I know of is that you may have overheated the metal a little.did you check the blade after hardening to see if it was harder than a new file ? ....Just my opinions,Bruce

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The Soul of the Knife begins in the FIRE !!!! Akti # A000223
 
I THINK it's 5160 (it's an old thin leaf spring). I haven't checked the hardness yet, but it's definitely harder than it was. It doesn't sand nearly as easily and has a different "ping" to it.

Oh well.... off to play with some Titanium next.
 
It could be 5160-1095,or a different alloy that the spring manufacturer thought would work.It was probably caused by the oils on the blade after each different hardening.Test the edge and if it isnt to soft then it isnt hurt and your good to go....Bruce

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The Soul of the Knife begins in the FIRE !!!! Akti # A000223
 
It's my first knife and although I had aspirations of something grand, I guess it will go on display to be a constant reminder of "look how far you've come."

I guess the wavy, blotchy marks in the steel will add character.
smile.gif


[This message has been edited by the4th (edited 05-27-2000).]
 
Thats what I did with my first one,it has its own display case above my desk to remind me of what they used to look like.Boy was I ruff with the scratches....... Bruce

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The Soul of the Knife begins in the FIRE !!!! Akti # A000223
 
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