Staying Sharp
By Nick Zdon
Everyone is familiar with the physical aspects of sharpness; a piece of material, usually steel, is shaped in such a way that two of its surfaces meet at an acute angle. It’s easy to physically see this description in the cutting tools we use everyday. However, it’s important to realize that sharpness is not something that is easily seen. Two blades of differing levels of sharpness placed side by side may appear to be the same. It’s not until we use each blade that we can choose the sharper of the two.
The most important steps of the sharpening process occur well beyond the limits of human sight. This is why it is important to have the concept of sharpness in our minds when sharpening a cutting tool. An inability to imagine and understand how the actions of the sharpening process effect an edge at an invisible scale will severely impede the sharpening process, and yield less than satisfactory results.
In a perfect world the sharpest of edges would taper until only a single molecule of steel remained at its edge. Of course, in our imperfect world this is impossible, not to mention impractical. A blade this sharp would break, fold over, or otherwise distort when used. But the only way to achieve excellence in anything is to strive for perfection. You should strive to attain, and preserve, this ‘perfect’ edge (in as much as is physically possible), and understand how every action of the sharpening process determines how close to perfect your edge will be.
In our imperfect world even the sharpest of blades carry microscopic scratches at their edges. These scratches create friction, making it more difficult for the edge to move through whatever material is being cut. A scratched edge is an inefficient edge and not in keeping with our ideal of perfection. It is our aim to sharpen an edge in a way that eliminates, or at least minimizes, surface scratches. In this respect we can actually think of sharpening as a process of polishing. We strive for a perfect edge that is impossibly smooth on both of its faces.
Keeping the idea of polishing in our minds, the sharpening process requires that we use tools that remove material in decreasing levels of abrasiveness. We start with the most aggressive files or stones, and remove material very quickly, leaving large scratches in our edge. We then move on to a file or stone that removes material less quickly, leaving the edge with smaller scratches than the previous tool. We progress in this manner until the steel shines like a mirror with no visible scratches. Moving to the next finer stone or file too soon is the most common error made in the sharpening process. This leaves scratches in the edge which we are unable to remove with subsequent tools, and requires regressing to previous stages of the sharpening process and repeating them.
Keeping the image of the perfect edge in your mind will allow you to understand how every stroke of the file or stone effects the edge in front of you. And with practice you will be able to see the sharpness of your own edge in your mind, and with every stroke of the file and stone bring it one step closer to perfection.
Photo: Even the most neglected of axes can be brought to a stunning degree of sharpness. The KnotKlipper pictured above was badly rusted, but with a steady and thoughtful sharpening process, the steel is exposed, polished, and sharpened to an impressive degree.
