The functionality of the kitchen knife blade depends largely on its geometry (longitudinal section) and grind cross-sections. When it comes to the longitudinal section, everything is clear since it determines the piercing and cutting capacity of the knife, as well as its mechanical and operational performance.
However, the cross-section is considered not less important as it has a bearing on the functionality, ease of use and cutting performance. Let us elaborate on it.
Simply put, the knife's cross-section is a taper elongated in length and strongly tapering to the bottom. The applied force causes it to move in a downward direction, with the lower angle of its active face overcoming the material resistance, and its side faces forcing apart the material being cut. The smaller angle of convergence of the lower edge (beveled angle) provides the optimum sharpness and high cutting performance of the knife, with the greater angle ensuring its resistance to damage and shocks.
For single-purpose knives the beveled angles may vary:
1. From 10° to razor sharp. This beveled angle provides the finest cut and is typical for a surgical aid;
2. From 10° to 20°. This beveled angle ensures a delicate cut for soft material and is common for fillet knives and slicers;
3. From 20° to 25°. This beveled angle can be found in professional chef's knives;
4. From 22° to 30°. This beveled angle characterizes boning, carving, fish, utility knives, as well as tourist and some kinds of hunting knives.
5. From 30° to 40°. This beveled angle is typical for knives involving strength such as a kitchen meat cleaver.
It is the geometrical cross-section profile that forms the beveled angle. Therefore, the kitchen knife blade grind cross-section is one of the most important characteristics determining the knife's purpose and performance.
Kitchen Knife Construction and Grind Cross-Section
Before we switch directly to the grind, geometry and types of section of the kitchen knives, we need to understand their cross-sectional construction and current terminology.
Well, if we divide the knife blade into two halves and take a look at its section, we will see the following components:
- Spine - upper blunt part opposite to the blade;
- Bevels - side faces tapering from the spine to the blade;
- Reliefs, also referred to as cutting faces - microbevels from reliefs to the cutting edge;
- Cutting edge.
In this regard, the following measurement parameters are important:
- Spine thickness;
- Thickness of convergence in the place of a minimum distance between the bevels;
- Beveled angle;
- Grind angle.
All these parameters are instrumental in determining the geometry of the section and the transverse section of the kitchen knife and ensure a certain quality and efficiency of the cut.
All Kitchen Knife Blade Grind Cross-Section Types and Their Function
Well, we can now move on directly to the kitchen knife blade grind cross-sections.
Double Bevel Grinds
The vast majority of commercially available knives feature a double bevel grind since it is considered the most traditional. The double bevel grinds include the following grind cross-sections.
1. Flat grind. It is an isosceles triangle with an acute angle pointing downwards. It has its bevels tapering from the spine down to the cutting edge and has no reliefs. It penetrates perfectly into the products and is good as a lever, however, the cutting edge is rather brittle.
2. Compound grind. It is called a "Scandinavian grind" with straight bevels without reliefs. It is very common in the knife making. It has a greater strength, but slightly worse cutting performance.
3. Compound grind with reliefs (and a five-edged taper with reliefs) is an optimal cross-section shared by many contemporary knife types and considered multiple-purpose for virtually any knife. The first type is a five-edged grind supported by reliefs, and the other type is a V-shaped grind with reliefs as well. It is characterized by an ideal combination of performance characteristics, i.e. good strength and high cut quality.
4. Convex grind. The main feature of this section is convex bevels without edges that provide incredible strength, high-quality cut of hard materials and capacity for chops and other forceful actions.
5. Full hollow grind is characterized by hollow bevels and used in the making of knives with high precision cut (for example, scalpels). It has unsurpassed cutting performance, but low strength and instability to loads.
Single Bevel Grinds
A single bevel (chisel) grind is inherent in Japanese rather than Western knives, and is considered highly tailored. It is used in the making of national Japanese varieties of knives, for example, deba or yanagiba. They have their blades ground only on the right or left hand side depending on the working hand (the relief is located on the working hand's side). The other side is absolutely flat. It provides excellent cut and high strength of the knife. You need practice and skill to work with this knife.
Asymmetrical Double Bevel Grind
It combines the advantages of both single and double bevel grinds and is notable for asymmetrical right and left hand faces, good physical and operational performance. It is also common for Japanese or professional handicraft knives.
It should be noted that these are only the basic and most common knife blade grind cross-sections, with their variations found in various combinations.
Types of Cutting Edges and Their Importance for Kitchen Knife Blade Grind Cross-Sections
So, we are now aware of different kitchen knife blade grind cross-sections and their main features. However, we cannot but mention that it is not only the blade geometry and cross-sectional profile that affect the cut quality, but also the type of the cutting edge. There are three types of cutting edges:
- Smooth, which are typical for most knives;
- Serrated, with teeth of the same or different heights;
- Combined, which feature both smooth and serrated types.
With the form of a smooth solid line, the first cutting edge type is the most common as it makes such knives multi-purpose and designed for the widest range of tasks. When pressed, it distributes pressure evenly to minimize resistance and ensure a smooth and even cut. It is well suited for most materials and products and is very easy to care and sharpen.
Nevertheless, the smooth cutting edge is not optimal for all products and sometimes a different cutting edge is required to tackle the task. A serrated blade is a cutting edge featuring a series of small teeth. It is more specialized, provides no smooth cut and is not suitable for all operations. It is more effective when dealing with hard or delicate products instead and is able to maintain the sharpness for a much longer time. It can be used to cut roasted steaks, bread and other pastries, cheese, citrus fruits and tomatoes, as well as frozen foods. However, it is problematic to sharpen such a knife at home; therefore, you will need to have it done by professionals.
Well, the knife can sometimes combine both cutting edge types, with one part being smooth and another serrated. The combined cutting edge is typically found in hunting, tourist or fishing knives, as well as in kitchen steak knives, enabling to effectively cope with pieces of any degree of roast.
For any knife to cause pleasure from working with it and to perform its functions well, it should impress with blade geometry, grind and have a suitable cutting edge type optimized for its purpose. Now, you are aware of what kitchen knife blade grind cross-sections are suitable for a particular range of culinary activities and will be able to pick up the right one.