knives from head bolts

[prarieboy]

Hey Folks This May be a silly question! This past weekend my Son the mechanic brought Me some head bolts from a ford diesel. We forged one close to shape then ran out time.Today I attempted to finish it got it thinned down and quinched in water. When I got it into the shop I noticed it was some what crooked and hit a couple of times while it was cold. That puppy snapped right into two pieces!!! The break looked very grainy. Kinda like a file.
 I have found a site (junkyard steels)that idetifies heavy duty bols as 4815 and heat treated bolts as 2330. I don't know which of  these steels the bolts may be.
 My questions are will this type of material work for knife if treated correctly and or did I just blow it by hittin it cold?     C-ya Bob

[Lin Rhea]

Bob,
     No, you should not hit a blade after hardening since it's so brittle. But that's the good thing about forging blades. You can learn a lot by mistakes and I have made plenty myself.

Most alloyed steels are labled with four numbers to denote the alloys and the carbon content. The last two numbers are the carbon content in one hundredths of a percent. If the steel has more than 1% carbon, it jumps to a five number identication, such as 52100. The last three numbers being the carbon content. 52100 has a full 1% carbon. 5160 has .60% or 6/10ths of one percent.

A good knife steel needs to have at least .40 maybe a little more of carbon to harden enough to make a serviceable knife.
                                 Lin

[Brad Singley]

I'm sure I will regret this but here goes.  Unknown steels are a false economy,  the one thing most of us do not have in abundance is time.  Use a known steel and you can learn that one steel very well.  I use O1, in about 90% of my carbon blades.  I know what that steel feels like when I'm forging, filing, hand sanding, and gringing.  This can only come with knowing a particular steel.
  I promise I do not want to come across rude or condesending.  I want you to build the best knife possibe and that starts with a known steel. Hope I did not make anybody mad.

[prarieboy]

Hey Folks
Thanks Lin for the heads up about how to tell whats what. My one brain cell must of quit firin about the time I hit it cold. I Knew that it was hardened back up!
 Brad You are not out of line I'm here to learn it's just my way to expiriment as cheaply as possible at the git go! Thanks for the git back. I'm sure that in time I will settle in on one type of steel.
 C-Ya Bob Thanks fer da  

[robtattoo]

Originally posted by Brad Singley:
I'm sure I will regret this but here goes.  Unknown steels are a false economy,  the one thing most of us do not have in abundance is time.  Use a known steel and you can learn that one steel very well.  I use O1, in about 90% of my carbon blades.  I know what that steel feels like when I'm forging, filing, hand sanding, and gringing.  This can only come with knowing a particular steel.
  I promise I do not want to come across rude or condesending.  I want you to build the best knife possibe and that starts with a known steel. Hope I did not make anybody mad.

I couldn't agree more Brad.