There is a lot of confusing information about sharpening Japanese or high end knives on the internet. Part of it is due that Japanese knives are relatively new in the West. Sharpening is foreign to most of us. The experts for years have told us to send out our knives, that the chance of damaging them, by doing it yourself is too great. The number of stones sets available has grown, offering more choices and confusion. Sharpening is personal, one person's ideal stone, is a nightmare for another. If that wasn't enough the sharpening world is divided into two camps, those who use jigs and those who free hand sharpen.
The jig systems are attractive, attach your knife and run the guide over it, and get a sharp knife. Critics of the jigs, will point out that the jigs struggle following curve of an edge. The supporters will say that criticism is over stated.
When I took the sharpening class for wood carvers, the tools were a variety of odd shapes, the winged vee shape being the most distinctive. It may be possible to sharpen an odd shape on a jig, I seriously doubt it though. With free hand its a simple matter of finding the right technique to sharpen an odd shaped knife. The versatility of free hand to handle any shaped knife, plus the fact that most top sharpeners on the forums, use it, is what convinced me to learn to sharpen free hand.
I think it was Murray Carter who said that sharpening was 99 percent mental and 1 percent the equipment. In other words the technique is more important then the equipment. To demonstrate this point, he sharpened a knife, using a cinder block and a piece of cardboard. The video can be found on you tube.
If there is a key to free hand sharpening its learning to hold the knife at a low angle, with as little movement as possible. This comes with practice. I did it by spending hours on a strop. Dave sells a guide, that is attached to the spine of a knife. The guide is placed on the stone, showing the correct angle. Another suggestion is to purchase an inexpensive knife, carbon is best, and learn how to sharpen it.
Jon Broida has a good video showing how to hold a knife, when sharpening.
The goal of sharpening is to grind a new edge into a knife and then refine it, by polishing it. The sign that a edge has been formed, is the burr, it ideally runs down the entire length of the blade. A burr feels like a piece of wire. Once a burr has been achieved the knife is turned over and the other side is ground until a burr is formed again.
The next step is to reduce the size of the burr. The phrase 'Chasing the Burr', is used to describe the process of reducing the burr. The process is the same as forming the initial burr, but the pressure on the knife gets lighter and lighter as the knife each time the knife is turned over, making the burr smaller and smaller. The better I've got at reducing the burr on the stones the sharper my edges have gotten.
The burr needs to be completely removed, to completely expose the edge. It is possible to reduce the burr, that it can no longer be felt, but it is still attached to the knife. This is my simple definition of the dreaded wire edge.
Deburring is the process of getting rid of the burr/wire edge. There is a wide range of opinion on how this should be done. Some feel it should be done at the very end. The theory being ripping metal away, during the sharpening process will weaken the edge. Taking off the burr when it is at its smallest, does the least amount of damage. The burr is removed with cork, a pencil eraser, the side of a cutting board, etc....
Dave Martell's ideal is to create a sharp edge, that will last. I believe he refers to it as a strong edge. He recommends that a knife be deburred after each stone, starting with the 1000 grit stone. The theory being that the edge and not the burr/wire edge is being worked with each stone. Dave has a deburring system that is a hard felt block and pad. The knife is drawn threw the pad, approximately ten times and then is stropped on the pad. After the pad, the knife is drawn threw the block again.
Very well regarded sharpeners deburr at the end. I use Dave's method. Both methods work, it just comes down to personal choice.
Trying to decide which stones to purchase, has created its fair share of confusion.
Water stones are the choice for most sharpeners. There are two types, ones that need to be soaked in water before use and the other needs only to be splashed with water. Both types of stones have their advantages and disadvantages, and it eventually boils down to personal choice.
What is important for a beginner is to choose stones that provide positive feed back. Typically softer stones provide better feedback. Bester, King, Nanawa Superstones, are good choices for the beginner. A harder stone such as a Shapton Glass Stone, would not be a good choice. Guess what my first set of stones were?
The next question is what grit stones should be purchased? Again for a beginner, only one stone is needed. A 1000 or 1200 grit stone. Sharpening means learning how to raise a burr and then reducing the burr. Until a person can do that, higher grit stones will not help. Nothing says you can't buy a set of stones, don't plan on using the higher or lower grit stones.
After you learn how to from a burr and reduce it, the next step is refining the edge, with higher grit stones.
Under a microscope a knife edge resembles saw teeth. As the edge is refined on higher grit stones, the teeth get closer and closer. A highly refined edge 10,000 grit or higher will glide through food and almost make the sides of food shiny. The down side of a refined edge is that it will lose its bite. On a tomato, which has a tough skin, a refined edge will glide over the skin, instead of cutting into it. Finding the edge that works best for you is a part of learning how to sharpen.
A low grit stone around 500 is used for setting bevels, and repairing damage such as chips. This is the stone that has created anguish and grief among sharpeners. It cuts metal so fast that a sharpener can quickly get into trouble. There are lower grit stones and diamond plates that remove metal even faster. I can see the purpose of them for repairing knives that have been severely abused. If I had a knife that was in that poor of condition, I'd be sending it to Dave.
Other items that needed for a sharpening kit are a flattening stone, and something to hold the stones.
Sharpening like any other activity that requires hand eye coordination, is an ongoing learning experience. Your knives will get sharper as you learn, but there is always something new to learn. Even the most advanced sharpeners are constantly trying out new techniques. This is the main reason I keep coming back to the forums. I'm looking for the next technique or idea that will take my sharpening to the next level.
Jay