Knife sharpening - facts and myths


Knife sharpening is a topic that always evokes a lot of emotions among knives enthusiasts. There are many myths around the subject of knife sharpening, which in fact introduce even more confusion and a helplessness among people starting their adventure with knives. Very often I have questions from our customers like: "Sir, I want to finally buy a decent knife, maybe even made of a powder steel, but I have no clue how to sharpen it and will I be able to handle it at all?". I will try to briefly share my own experience that I have gathered over many years of my knife passion. These were experiences full of disappointments at the beginning.

We'll start with the most important thing. 99% of people will never learn to sharpen a knife „by hand” without using a sharpening system. Personally, I know a few people from the knife enthusiasts community who, after many years of trial and error, have acquired this skill and can sharpen a knife on the proverbial "field stone" or like my friend "Micho" on a tea cup turned upside down, but these people statistically there is very little and you will probably never find yourself in this esteemed group. I have personally tried to master this arcane art for many years, using all sorts of commercially available whetstones, rods and "miracle" budget sharpening systems. The result was always one, hours spent sharpening the knife and disappointment painted on my face. Of course, after my treatments, the knife cut somehow and was not drastically dull, but the test with cutting a sheet of paper into strips never passed. You will ask why this happened? You can say, I probably had a bad abrasive material, some "Chinese crap", because if I had a decent diamond whetstone, my knife would sharpen itself. No. None of these things. And here we come to the heart of the problem called "sharpening angle".

The fundamental condition for success in knife sharpening is maintaining a repeatable sharpening angle. Without this condition, we will never sharpen the knife properly. If you are not a member of that respectable group of 1% of the population of knife enthusiasts who can maintain the same sharpening angle "by hand", then you have only one choice - you need to get a decent sharpening system. Only the sharpening system guarantees the repeatability of the sharpening angle. What sharpening angle we set on our sharpening system depends on the type of knife and some of our personal preferences. In simple words, the greater the sharpening angle, the more resistant to wear and damage the cutting edge is, but at the same time the knife will be less effective in cutting. On the other hand, the smaller the sharpening angle, the better and more aggressively the knife will cut, but it will be more susceptible wear and damage to the cutting edge. For example, folding knives, i.e. HERMAN KNIVES folders, are sharpened at 20 degrees per side (total angle is 40 degrees), survival knives such as LKW, TD KNIVES, RATO KNIVES, BM KNIVES are sharpened at 25 degrees (total angle is 50 degrees), and kitchen knives are sharpened at 15 degrees (total angle is 30 degrees). We can change these angles in the range of plus/minus 3-4 degrees and then our knife characteristics will change according to the principle described above.

Finally, I would like to talk about sharpening stones, in other words, whetstones. The easiest way to sharpen knives can be divided into two types: diamond and ceramic. Without going into too much detail and without complicating the subject, we recommend diamond whetstones for sharpening more advanced "harder" steels such as M390, M398, ELMAX, Vanadis4E, CPM 3V, DAMASTEEEL, DAMACORE, BALBACH, . Their advantage is the greater aggression of collecting material, the disadvantage is durability. Ceramic whetstones are usually more durable and last longer, but they collect material less aggressively and a knife made of "difficult" steel simply sharpens longer. It is very important to use the right gradations and choose them according to the condition of the knife you are going to sharpen. From our own experience, we advise the following set of diamond sharpeners. Gradations 80 and 200 (or 240) will work in three cases. The first is when we are a knifemaker and we want to create a cutting edge after the grinding. The second is a situation in which we have a damaged (chipped, wavy) cutting edge. The third case is when we want to change the sharpening angle. If we just have a dull knife, but not drastically dull, we recommend starting with gradation 600, 1000, 3000 and these are diamonds, then 8000 gradation is already a stone whetstone (agate) and finally leather. We sharpen with all gradations "against the grain", while with the skin we remove the micro fold working "with the grain"

In the next article, I will try to present the advantages of manual sharpening systems and discuss the individual models of the KAZAK POLAND sharpening systems we offer, of which we are an authorized representative.


                                             Author: Maciej Dziekanski, Polish Custom Knives Team