When thinking about sharpening knives, the most common goal people associate with the task is to make the knife sharp. Of course, that's definitely a large component of the job - to create a refined edge so it effortlessly separates the object being cut. The other aspect, which is less commonly considered, is the material removal from the edge.
A professional knife sharpener should aim to create the sharpest and most well-structured edge possible while simultaneously removing the least amount of material as possible.
To sharpen a knife, some metal removal is necessary to reshape the edge. But, many people don't consider just how much material is removed, and how they can continue to refine their technique to accomplish the least amount of material being removed while still achieving incredible sharpness.
Removing too much material from an edge is bad for two reasons:
- It will shorten the lifespan of the knife's usability
- Removing too much material can permanently alter the appearance of the knife
Customers want their knives to stay in great shape for a long time, and some owners of higher-end cutlery can be very concerned about the aesthetics of their expensive knives. To keep your customers happy, always try to remove the least amount of material unless otherwise instructed by your customer.
The sharpening equipment that is used to sharpen the knife plays a big role in how much material is removed. Electric sharpening equipment will remove material from an edge must faster than manual sharpening equipment. It takes a ton of practice with electric sharpening equipment to refine your technique so a minimal amount of material is removed.
In addition to using the right equipment (or being very well practiced) the other factor to consider about material removal is the sharpening angle. Different knives will require different sharpening angles. Most knives will require a sharpening angle within the range of 15 to 30 degrees per side. If you sharpen the knife and don't use correct angle for the knife, you will undoubtedly remove too much material from the edge. For instance, if the manufacturer of the knife created the edge at 24 degrees per side, and you use 15 degrees per side to sharpen the knife, you will be re-profiling the bevel angle by 9 degrees. Not only will you remove too much material from the edge, it will also take you significantly more time to sharpen the knife because you will be removing an unnecessary amount of materiel.
The way to find the perfect balance between making the knife super sharp and removing the least amount of material is to use a manual, angle-guided knife sharpening system and set the sharpener's angle settings to match the current angle of the knife's edge.
How do you know what the original sharpening angle is? That's easy. Color the knife's edge with black permanent marker and then do some trial-and-error with the angle settings on the sharpener. Use a fine stone to test different sharpening angle settings until you find an angle setting that allows the stone to remove the coloring from the edge evenly.