Custom Knife - Which Steel? September 10 2014, 0 Comments

Now that your design is done you should pick the materials for your knife blade, the steel.

  • Carbon steel
  • Stainless Steel
  • Damascus steel (a subject all by itself; not discussed in this chapter)

Carbon Steel

The most commonly used Custom Knife Carbon Steels are:

  • O1, O2, O6 steel
  • A-2, good beginners steel in case you want to work on your knife yourself
  • L6 (band saw steel), mostly for chopping knives like machetes, some Bowie Knives
  • W-1 (spring steel), very hard but flexible
  • W-2 (tool steel), good edge holding, will keep sharp but easy to re-sharpen
  • 1095 (high carbon steel), often used in Damascus, good forging, good edge holding, very fine grain
  • 52100 (ball bearing steel), good for forging
  • 5160 (another spring steel), excellent CS knife steel, will show a Hamon nicely
  • 5180 excellent CS knife steel, will show a Hamon nicely 

Hamon = transition line on/in the steel,the mark of a differential heat treatmentCustom Handmade knife steel 

Stainless Steel

Most commonly used

  • 420 (every knife classified as ‘stainless’ is usually 420) also known as AUS-4 and 4A.This is the classic cutlery steel, medium edge holding capability, easy re-sharpening. Most kitchen knives are made of this steel. It is also known as Solinger Stahl.
  • 440 group, AUS or A (AUS and A usually refer to a Japanese manufacturer of the steel) Steels of this group have different names depending on the country of origin and the manufacturer.
  • 440 A, 6A, AUS 6 Medium Carbon, high Chromium. A knife marked with 440 stainless steel is usually made out of this steel grade. Chinese manufacturers like to use this steel (marked 440) or the 420 (marked Stainless Steel)
  • 440 B, 8A, AUS 8 More Carbon, high Chromium. The better cutlery steel, commonly used by Cold Steel.
  • 440 C, 10A, AUS 10 High Carbon content, high Chromium. 440C (nick name ‘old faithful’ with some custom knife makers) has a higher Chromium content than 10A and AUS 10.
  • ATS 34 (Japanese), CM 154 (US)Both have high Carbon + 1% and high Chromium + 14% and are commonly used steels by custom knife makers.

A custom knife maker usually has no lower a grade than 440 C for his knives, some use D2 or modified D2 (the well-known planer blades)

Grain Structure in a conventional steel, produced by melting the metal.

Powder Metallurgical Stainless Steel, PM Steel

RWL 34, CPM 154, CPM S30V, CPM S35VN, CPM S90V, M390, N690 etc (just to name the most common ones; there are also PM Carbon Steel available and one company offers PM made Damascus steel)

These steels rival the carbon steel in

  • the fine grain
  • the edge holding capability and
  • the toughness.

They are made in a sophisticated process, they are not molten like all the other knife steels but made in the Powder Metallurgical Process.

Grain Structure in a PM Steel (powder metallurgical made) steel

                                                                                                                

They vary in their content of Carbon and Chromium but are all considered high in both. The additives like Vanadium, Molybdenum, Niobium etc vary also and will give the special characteristic of the steel like high toughness, high wear resistance etc.

Knives made out of these steels require extra care in the Heat Treatment usually made by the custom maker himself. They combine a supreme edge holding with toughness and will be very corrosion resistant. Manufacturer of production knives and cutlery do not choose these steels often as they are fairly complex to deal with and also expensive as a raw material.

Nevertheless they are the choice of the custom knife maker to demonstrate his skills and ability to make a very high grade knife. The user of such a knife will be awarded with beauty and a tool of supreme quality and superb edge holding.

We were just touching the most common steels used for knives, the in-depth discussions of some ‘steel junkies’ require a good and fundamental knowledge steel itself and a knowledgeable knife maker will be able to assist you with good advice to choose the best steel for your knife.