Knife making

Knife making is the process of manufacturing a knife by any one or a combination of processes: , forging to shape, welded lamination or investment cast. Typical metals used come from the carbon steel, tool, or stainless steel families. Primitive knives have been made from bronze, copper, brass, iron, obsidian, and flint.

Different steels are suited to different applications. There is a trade off between hardness, toughness, edge retention, corrosion resistance, and achievable sharpness. Some examples of blade material and their relative trade offs:

Unusual non-metallic materials may also be used; manufacturing techniques are quite different from metal:

The initial shaping of a knife is done through forging or blanking.

When forging, the blade material is heated to a high temperature or forging temperature in a forge and shaped with a hammer on an anvil to achieve the desired shape, often to near final dimension, where very little stock removal, if any, is required to finish. Steel can be folded either to form decorative pattern welded steel or to refine raw steel, or as the Japanese call it, tamahagane. Grain size is kept at a minimum as grain growth can happen quite easily if the blade material is overheated.

In a mass production environment, or in a well equipped private shop, the blanking process is used to make "blade blanks." This can be achieved by a number of different methods, depending upon the thickness of the material and the alloy content of steel to be cut. Thinner cross section, lower alloy blanks can be stamped from sheet material. Materials that are more difficult to work with, or jobs that require higher production volume, can be accomplished with water jet cutters, lasers or electron beam cutting. These two lend themselves towards larger custom shops. Some custom knife makers cut their blanks from steel using a metal-cutting bandsaw.

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