Chisels for a knife

[porthos]

i have many old chisels. wondering if they are suitable for a knife. (i would think that they are). and if so; i do not own a forge. how about a ox/acetelene torch??

 

[RJSakowski]

Most, if not all, the wood chisels that I own are a plain high carbon steel. They will take a keen edge,as desired for wood working but the edges aren't all that durable. In contrast, the better modern day knives are usually an alloy steel that is better suited to maintaining a sharp edge without a need for constant resharpening.

IMO, an oxyacetylene torch isn't the best heat source as the steel is too easily oxidized due to the high flame temperature. There is a tendency to burn the carbon out of the surface of the steel as well. You could get by using a reducing flame. Uniform heating is also an issue. To work around this problem, make a makeshift oven by stacking firebrick.

I would assume that you intend to reshape the chisels to create the knife profile by forging rather than grinding. This is best done with a proper anvil. There is only a short amount of time after the blank is removed from the heat source until it is too cold to work and having a good setup is essential.

 

[porthos]

let me be a little more clear about chisels. i have probably a dozen large metal center punches and metal chisels. i will work on a forge construction..

 

[pontiac428]

let me be a little more clear about chisels. i have probably a dozen large metal center punches and metal chisels. i will work on a forge construction..

I initially thought you were asking about metal chisels and not wood chisels, because what's a wood chisel? More specific, what's this wood you speak of? I know nothing about it... /sarcasm.

Metal chisels are made of tough alloys that are impact resistant, but not very hard compared to blade steel. Think 4350 vs. M2, one is selected to take a beating and won't hold an edge, and the other is good for cutting tools but will shatter or break under hammering.

Some tough alloys can be hardened enough to make a blade, but won't always perform well as a blade. Spring steel is a good salvage material to make general purpose blades out of, it heat treats to the point where grinding is necessary to form an edge. Many wood tools and utility blades have been made of old leaf springs.

Your chisels and punches would make good chisels and punches by reworking into useful shapes, maybe even good hammer heads if you draw the temper soft enough to not chip. They would make good farm implement blades where they must take a beating more than they need a fine edge, like swather blades or plowshares. Mower blades are in that range, too, not that I'd make one from old chisels.

Chisel steel would make a fantastic backbone for laminate or damascus steel knife blades, where the cutting edge is formed from harder steel and the balance is tough steel, if you want to dabble in that rabbit hole.