There are not that many knife sharpening techniques
Despite the fact that there are dozens, no probably hundreds of different knife sharpeners, there are actually not that many different knife sharpening techniques. Lets look at them.
You have two basic choices for sharpening a knife
In fact if you’re looking to sharpen a knife there are only two basic ways to do it, though many variations of technique. The two basic ways to sharpen a knife are to do it yourself or to get somebody else to sharpen your knife for you.
It may sound silly suggesting that you pay somebody else to sharpen your knives. In fact many professional chef’s send their knives out to a professional knife sharpening service from time to time rather than taking the time to sharpen their knives themselves.
It’s unlikely, if you’re new to sharpening knives, that you’re likely to get as good a result doing it yourself as sending it out to a sharpening service. Professional knife sharpeners have been doing the job for many years and will produce a better result than most beginners.
However lets assume for a moment that you’re looking to learn about knife sharpening techniques so that you can sharpen your knives yourself.
You need to understand the difference between sharpening and honing a knife
There are actually two aspects to sharpening knives. Many people confuse the two. You can either sharpen a knife or you can hone it.
Sharpening a knife requires you to remove metal from the blade to restore the edge. Honing simply refers to restoring the edge by drawing it across a hard surface. When you hone a knife you do not remove metal from the blade.
As you use a sharp knife the very finest part of the edge gradually bends over. It’s microscopic and you won’t see it, but the finest part of the blade has become blunt. The very finest part of the edge has turned over.
If you run the edge of your knife over a hard surface then you will restore the edge by lifting it back up until it’s straight.
In fact many people refer to a “sharpening” steel when it is in fact a “honing” steel. A steel does not remove metal off the blade in most cases, though not all.
To sharpen a knife you need to remove metal from the blade. Where the edge has become sufficiently dulled that honing will no longer restore the edge it is then time to sharpen it by removing metal. This restores the edge of the blade when honing no longer works.
To remove metal from the blade it needs to be applied to another surface that is harder than the metal in the blade, and drawing the knife across this hard surface, or drawing the surface across the knife, abrades the metal and removes small amounts.
Not only should the knife be drawn across a hard surface but it also needs to be drawn across that surface at the correct angle. Get the angle wrong and chances are you’ll get a very poor result.
The angle depends on a number of things, particularly the type of knife. Japanese knives, for example, tend to require a lesser angle than most common kitchen is.
However as a general rule 20 degrees is about right for many knives.
The shallower the angle the sharper the knife. But the edge won’t last as long. The steeper the angle the more durable the edge will be, but it will not be a sharp.
That’s the basic principles for sharpening a knife. Draw the edge of the knife, at the correct angle, over a hard surface to remove metal from the blade.
How you achieve that is, however, a different matter. There you have many many choices. However despite the fact that you have hundreds of different knife sharpeners to choose from the basic principle of sharpening a knife remains the same. Different knife sharpeners are merely different ways of removing metal from the blade.
That’s not to say that all knife sharpeners work as well as others, in fact the reverse is true, there are some that are much better than others. But all work on the same basic principle.
You can boil most knife sharpening techniques down into some simple categories, or different types of sharpener.
Knife sharpening stones
A sharpening stone, often called a Whetstone or Wetstone, is either an artificial or natural substance, harder than a knife blade, over which you draw your knife, at the correct angle, to sharpen it. The task is done manually and the person performing the sharpening technique needs to determine the correct angle to hold the knife and then hold it at that angle during the process.
There are many varieties of knife sharpening stones, with different grits (or fineness of abrasive). Some are natural stone, some artificial stone and some have impregnated surfaces with abrasives such as diamond. Experienced sharpeners will have two or three stones of varying grit. They commence sharpening on the coarsest stone and work through to the finest. Some stones are combination stones, with different grits on each side.
But the basic principle of using a stone is the same in all cases.
Manual knife sharpeners
A manual knife sharpener is one where the person sharpening the knife draws the sharpener over the blade of the knife. Some basic manual knife sharpeners can be very inexpensive, often around $10 or less, and can be effective in some circumstances, though some practice is needed first. However they are unlikely to produce as good a result as some more advanced sharpening methods such as using a quality sharpening stone. And they remove quite a bit of metal from the blade of the knife shortening its life.
Electric knife sharpeners
Electric knife sharpeners use a small motor to rotate the abrasive surface and the user draws the knife through a slot allowing the rotating abrasive to abrade the edge of the knife. In most cases the slot into which the knife is put determines, and holds, the angle of the knife correctly so the user does not need to do this. In many models there are choices of different sharpening angles.
Those are the basic knife sharpening techniques available to any knife owner. Assuming the decision has been made not to send a knife to a sharpening service the owner of the knife needs to determine which technique they shall use.
Learning to sharpen a knife with a stone can produce an excellent result, but takes a lot of practice. In particular it’s difficult to hold the knife constantly at the correct angle.
Simple manual knife sharpeners will do the job in many cases but are not likely to produce as sharp a knife as you are likely to get from a good stone, after practice.
Electric knife sharpeners are effective, quick and the more expensive versions will produce a good result. However they are more bulky than most other knife sharpeners and so need to be stored. The top of the line electric sharpeners are also relatively expensive.
An electric sharpener also removes quite a bit of metal from the blade of your knife. If you use a sharpening stone your knife should last for decades. If you use an electric knife sharpener it probably won’t.
So If you’ve been looking for knife sharpening techniques then you’ve got a few decisions to make. Are you willing to invest the time and effort into learning to use a stone? Do you want a cheap and simple sharpening tool that will produce a quick result, but perhaps not quite as good as some other tools? Or do you want to invest more in a quality electric knife sharpener, find somewhere to store it and learn to use it?