Sharpening and honing is no big deal as long as you have the right whetstone, sharpening angle, and grit.
Sharpening kitchen knives is the battle against dull blades. Anyone who uses their kitchen knives regularly will eventually notice that they lose their sharpness. This is especially frustrating with a favorite knife that’s used every day.
What to do? Now two questions arise: What’s the best way to sharpen, and how do I do it correctly?
With the right sharpening tool and a little practice, it actually goes quite quickly. It’s fun, and the satisfaction of a sharp cut afterward shouldn’t be underestimated.
There are many different solutions for quick touch-ups. Everyone can find the right sharpening tool for them among the numerous options available.
Before deciding on a method, however, you should understand what actually happens during sharpening. One of the most important fundamentals is the correct sharpening angle.
Why Do Kitchen Knives Get Dull?
No blade stays sharp forever. When you cut with a knife, the fine cutting edge is subjected to stress and gradually changes. Depending on the type of steel, the blade’s geometry, and how the knife is used, this can happen at different rates.
A good kitchen knife, therefore, doesn’t just have to be sharp once. It should also be easy to resharpen.
However, it’s not just about maximum sharpness. For practical use, the stability of the blade and its ability to hold its edge are also crucial.
Sharpness and edge retention—an important trade-off
The correct cutting angle for a knife is always a compromise. The angle must balance two conflicting requirements: sharpness and durability.
A very finely ground cutting edge can be exceptionally sharp. At the same time, the cutting edge becomes more delicate.
A more stable cutting angle makes the cutting edge more durable. As a result, the cutting edge becomes slightly less refined in terms of geometry.
So, when sharpening a knife, it’s not just a matter of choosing the smallest possible angle. The right angle must be suited to the knife, the steel, and its intended use.
Choosing Between the Cutting Angle and the Grinding Angle
Two terms are often confused here: cutting angle and grinding angle.
The cutting angle describes the total angle of the cutting edge.
The grinding angle, on the other hand, is the angle at which a single side of the blade is drawn across the whetstone or another sharpening tool.
For a symmetrically sharpened knife, the grinding angle is approximately half the total cutting angle.
For example, if each side of the blade is ground at 15 degrees, the cutting angle is approximately 30 degrees.
As a rough guideline, about 10 to 15 degrees per side is suitable for many kitchen knives. However, the actual appropriate angle depends on the knife, the steel used, the cutting edge geometry, and the intended use.
A smaller angle can result in a very fine-cutting but more delicate edge. A larger angle generally makes the edge more stable.
When actually sharpening, one thing is therefore crucial: The sharpening angle must be kept as constant as possible.
What really makes a kitchen knife sharp?
Sharpening knives ensures safety when cutting. The sharpness comes from the cutting edge. During sharpening, material is removed from the blade and the cutting edge is rebuilt.
The grit size of the abrasive also plays a role.
A coarse abrasive removes a relatively large amount of material. This may be necessary if a knife is very dull or if the cutting edge has been damaged.
A finer grit can then be used to further refine the cutting edge.
However, the fineness of the abrasive alone is not the decisive factor. The correct sharpening angle, a cleanly finished cutting edge, and the subsequent removal of burrs also determine the actual cutting performance.
For everyday kitchen use, therefore, the goal is not necessarily the sharpest possible edge. Above all, a cleanly sharpened and stable cutting edge must be suited to the knife and its intended use.
The False Promise of a Chef's Knife That Always Stays Sharp
Many manufacturers, especially online, offer knives that are supposedly designed to stay sharp forever.
Such knives simply do not exist.
At some point, you’ll notice that the sharpness begins to fade. Every blade is subjected to stress through use and undergoes changes.
Some knives are marketed as having particularly hard coatings. Such a coating can significantly slow down the wear and tear on the blade. However, it does not make a knife permanently maintenance-free.
Even a coated blade changes with use and may eventually need to be resharpened.
When resharpening coated blades, it’s also important to consider the function of the coating and how it interacts with the cutting edge.
Ceramic Knives
Another so-called “always sharp” knife is the ceramic knife.
Ceramic knives can have a very high initial sharpness and remain sharp for a long time due to their high hardness. At the same time, they are more brittle than many types of knife steel.
If the blade has become dull or damaged over time, resharpening is more challenging.
Diamond abrasives are particularly suitable for resharpening ceramic knives. These are available in various grit sizes
Diamond as an abrasive
Diamond abrasives differ from traditional whetstones in that the abrasive diamond grains are mounted on a backing.
In many diamond grinding discs, industrial diamonds are mounted on a metal backing. The diamond grains are responsible for the actual material removal.
One advantage of such abrasives is their high hardness. This allows them to be used even on very hard knife steels and makes them suitable for working on ceramics as well.
Depending on the design, diamond sharpeners can be used dry. Thanks to the rigid backing, they can also be made to be very flat.
However, diamond is not automatically the best solution for every kitchen knife. Here, too, it depends on which knife is to be sharpened and how much material needs to be removed.
Which method is best for sharpening knives?
There are many types of abrasives and sharpening methods for kitchen knives. There is no single “right” way.
Which method makes sense depends on the knife, the condition of the blade, and, not least, your own experience.
The Whetstone
The classic whetstone offers very direct control over the sharpening process. With a little practice, you can achieve an excellent edge.
In the next section, we’ll explain in detail what types of whetstones are available, what grit size you need, and how to properly prepare a whetstone.
Continue to Part 2: The Whetstone—A True Classic
The Sharpening Steel
A sharpening steel can be suitable for quick touch-ups. Depending on the design, it can realign the edge or remove additional material.
In the third part, we’ll discuss how different sharpening steels work and how they differ from other sharpening methods.
Fixed-Angle Sharpening Systems
One of the biggest challenges in freehand sharpening is consistently maintaining the correct angle.
Fixed-angle sharpening systems can help with this. The blade is held in a defined position, and the abrasive is guided at a predetermined angle.
Roll Sharpeners and Grinders
Roll sharpeners and electric grinders can also make it easier to maintain a specific sharpening angle.
Which method is best depends on the knife, the type of steel used, the condition of the blade, and, not least, your own experience.
cSharpening Kitchen Knives—A Summary of the Most Important Pointst
With a little practice, it’s entirely possible to sharpen kitchen knives yourself. The key factors are the right abrasive, the correct sharpening angle, and a controlled motion.
The goal isn’t to sharpen every knife as aggressively as possible or at the narrowest possible angle. What matters most is a cutting edge that’s suited to the knife, the type of steel used, and its intended use.
If you understand what happens to the cutting edge during sharpening, you can keep your kitchen knives sharp for a long time and assess the condition of the blade yourself.
In the next section, we’ll take an in-depth look at the classic tool of knife sharpening: the whetstone.
We’ll take a look at natural and synthetic grinding stones, water stones, and oil stones, and explain what’s important when it comes to grit size, preparation, and use.
FAQ
Frequently Asked Questions About Sharpening Kitchen Knives
What is the correct sharpening angle for a kitchen knife?
As a rough guide, an angle of about 10 to 15 degrees per side works well for many kitchen knives. However, the appropriate angle depends on the knife, the type of steel used, the blade geometry, and the intended use. A smaller angle can result in a finer, but more delicate cutting edge. A larger angle generally makes the cutting edge more stable.
What is the difference between the sharpening angle and the cutting angle?
The grinding angle refers to the angle of a single side of the blade relative to the abrasive. With a symmetrical grind, the total cutting angle is determined by both sides. For example, if each side is ground at 15 degrees, the total cutting angle is approximately 30 degrees.
Can you sharpen a kitchen knife yourself?
Yes. With the right sharpening tool and a little practice, you can sharpen kitchen knives yourself. It’s especially important to keep the sharpening angle as consistent as possible and to work on the cutting edge evenly.
Which is better: a whetstone or a sharpening steel?
Both serve different purposes. A whetstone specifically removes material from the cutting edge and is suitable for actual regrinding. A sharpening steel, depending on the design, can work on the cutting edge or realign it and is particularly suitable for regular touch-ups.
What grit size do I need to sharpen a kitchen knife?
That depends on the condition of the blade. A coarse grit removes material more quickly and is suitable, for example, for very dull or damaged blades. Finer grits are used to further refine the cutting edge. For normal kitchen use, a medium grit is often sufficient as a starting point.
Can you sharpen ceramic knives yourself?
Ceramic knives can generally be resharpened, but due to their high hardness and brittleness, they are more challenging to work with than many steel knives. Diamond abrasives are particularly suitable for resharpening ceramic blades.
