Everyone knows the value and importance of keeping a good knife handy at all times, and most of us understand that an essential part of keeping that knife in tip-top condition is keeping it sharpened.
A sharp knife is far easier to use, safer and more effective than a dull one, and most of us have probably gotten cut before trying to saw through some tough material using a knife with a worn-out edge.
But like most things there is a point where you can be too fastidious, too aggressive and too proactive when it comes to keeping your knife’s edge serviceable. This begs the question:
Is it possible to over-sharpen a knife, either too often or too much? Yes, it is possible to over-sharpen a knife. Sharpening is a reductive process, whereby material is removed from the blade to produce an edge using a variety of abrasive tools in order to increase cutting efficiency. Sharpening too often will reduce blade life, and ceaseless sharpening and refining of the edge past the point it is suitable for the task at hand will only make the edge fragile.
Periodic honing of a knife that is used regularly or sharpening only after periods of heavy use is all that is required to keep your knife in good shape. Sharpening as a hobby, compulsion, or through the misguided belief that continual sharpening will always produce a finer and finer edge will only send your knife to an early grave. We’ll share a little info on the subject with you in the rest of this article.
Sharpening Removes Material
Sharpening of a knife using a natural stone, metal file, sandpaper, ceramic rods, or even a powered wheel is a “destructive” process, though if it is done properly that destruction is controlled and minimal.
Nonetheless, the swarf that is left behind on your sharpening device used to be part of your knife!
If you have ever had your granddad’s or great-granddad’s pocket knife handed down to you and you noticed that it had a skinny profile akin to a fillet knife you can rest assured that knife was probably sharpened countless times before it came into your possession.
Every time you sharpen the knife, every pass you make with your tool, will shorten the overall width of the blade ever-so incrementally.
For this reason, one should take care to use the appropriate sharpening tools and procedures so that a usable edge can be given to the knife with the minimal amount of material removed. Only by sharpening your knife with skill and attention to detail can you obtain its maximum usable life.
Some Tools are More Aggressive than Others
It is surprising how many different kinds of material and how many specialized tools can be used for sharpening a knife. Any tool or material that feels gritty to the touch is going to be exceptionally aggressive when it comes to sharpening a knife, and should only be used in cases where no other option exists or extreme reprofiling of the edge or bevel is necessary.
Sandpaper, metal files and diamond grit rods will all take comparatively big bites out of your blade with each pass, where smooth whetstones, leather and industrial ceramics are much milder.
Over time, you will definitely notice your blade getting narrower and narrower.
Additionally, if you are a sloppy or unskilled sharpener of knives you are going to be whaling away on the edge for longer and with more force than someone who is skilled, and knows what they are doing.
An aggressive tool, too much pressure and a lack of skill is the perfect recipe to trash a blade in short order!
Know When to Sharpen, and When to Hone to Extend Blade Life
While it is true that your knife will serve you best if you consistently touch-up the edge after a particularly tough chore or several days of regular use it would be wise of you to learn the difference between a proper sharpening and a quick repair of the edge, known as honing.
Broadly speaking, when you have to break out multiple sharpening stones of varying grits, files and even a powered sharpening tool, you are doing so to restore an edge that is badly mauled from a considerable amount of neglect or serious damage, with nicks, gouges, and obvious dents in the edge.
Honing on the other hand is what you do when you notice the knife is just not quite cutting like it normally does, perhaps refusing to glide through twine or tape like it used to, or perhaps you have to saw it back and forth a little bit in order to get through tougher materials.
In case of the latter eventuality, all that is needed most of the time is a single, fine grit stone or even a purpose-made honing steel, similar to the kind used by professional chefs in kitchens all over the world.
Honing the edge is, in essence, a very light, very mild sharpening, one designed only to restore an edge that is otherwise in good repair.
Honing works by realigning the very apex of the edge, known as the burr, which is so fine that it cannot normally be seen with the naked eye. It is the condition and alignment of the burr that makes an edge truly sharp.
Honing helps keep the burr in proper alignment and proportion, maintaining the edge that you work so hard to establish in the first place and prolonging the amount of time between proper sharpens.
By making sharpening less necessary, and therefore less frequent, honing helps to prolong the life of your blade and ergo your knife.
Over-sharpening a knife, either by sharpening too often or working at the edge for too long will do nothing except accelerate the demise of your knife by removing more material than is necessary to establish a working edge.
By selecting proper sharpening tools, and using correct techniques the lifespan of your knife can be extended.