WHAT TO CONSIDER WHEN CHOOSING A WHETSTONE
by Sami P., 22.01.2022
I keep coming across comments where people tell me about problems with knife sharpening. For example, getting a particular knife sharp can be difficult or even impossible. The problem is often caused by completely wrongly chosen whetstones.
As a whetstone professional, I have to admit that it is easy for even the most experienced sharpeners to make a mistake. This is because there are significant differences in the efficiency of whetstones - and they often depend on the metal of the knife being sharpened. But the sharpening technique also plays a significant role.
A WORD OF WARNING ABOUT THE QUALITY OF WHETSTONES
There are several inferior quality whetstones available. They usually come from China, and the problem with them is that they are very soft. In these stones, you can easily 'drown' your knife when you use a slightly wrong angle, and the knife sinks into the whetstone without much pressure.
At the other extreme are hard, often extremely hard coarse stones that cannot remove any metal.
THE CHALLENGE OF CHOOSING A WHETSTONE
It is often assumed that the hardness of a knife's heat treatment determines how easy it is to sharpen the knife. In my experience, this is partly true, but there are exceptions. However, some carbon steel knives with a hardness of 60-62 are more straightforward to sharpen than specific stainless steel knives of 58.
I am talking here about the toughness of the metal. Certain types of metals can be much more challenging for stones than others.
At the other extreme are metals that are both hard and tough. These may well include powder steels, for example, SG2 and S30V.
MAIN CRITERIA FOR SELECTING A WHETSTONE
Always choose the largest possible stone.
Cheaper stones are often short and narrow, for example, 180 x 60 mm, and are hopelessly too small. However, you get much more power from the same stone when you increase its size closer to the industry standard dimensions of 210 x 70 mm. At the same time, it becomes much easier to sharpen larger knives.
You will always need at least two grit. Traditionally, these have been 1000 and 3000. However, in recent years, manufacturers have changed their style slightly and, depending on the brand, you could say that you should choose stones with a grit of 800-1 000 and 3000-5 000.
When choosing whetstone grits, the old basic rule of thumb is: double the grind and choose the closest one you can find. For example, 400 x 2 = 800 -> 1 000, 1 000 x 2 = 2 000 -> 3 000, and 3 000 x 2 = 6 000 -> 8 000.
SOFT OR HARD WHETSTONE?
By soft stone, I mean what is known as surface-soft stone, which is often more pleasant to use than completely hard stone. Soft stone often produces a slurry or muddy layer. This aids in sharpening carries away the loose metal, and makes the whole process feel pleasant. Often, the so-called feedback is felt more strongly in these stones.
On the other hand, the hard stone is significantly better suited to sharpening tools such as chisels and plane blades. I have also found that beginners get into sharpening better with hard stone. Hard stone is more forgiving of beginner's mistakes.
Inevitably, even this division is not always clear-cut. For example, I have often said that hard stones are more effective than soft ones. However, you can increase the efficiency by making the coarse stone softer and letting the loose abrasive particles do the work.
SPLASH-AND-GO OR SOAKER?
Almost without exception, the stones that have come onto the market since 2000 have been low-water-using, so-called splash-and-go stones. But, of course, the definition of an S&G stone is rather broad. Still, in principle, any stone ready for sharpening immediately after a light chipping operation can be counted as such.
S&G stones are often harder, but many also have a soft surface.
S&G is, of course, the easier choice in today's busy world. But, at its best, Sharpening can be a very tidy job - when done with stones that require a minimal amount of water to work.
Traditional, full soaker stones have not been new to the market in recent years. Instead, a new category of semi-soaker stones has emerged. I include stones that require at least 5-10 minutes of water to work well in this category. But, on the other hand, even these stones can often be handled with a shorter amount of water - all you need is a point of sharpening where you can quickly pour more water over the stone.
Semi-submerged stones often give a better feel for Sharpening. This can also make sharpening an experience and an experience to remember. I often hear better feedback on this class of stone precisely regarding usability.
THE CHALLENGE FOR THE BEGINNER SHARPENER
Often the knives of someone considering buying a sharpening stone are already in bad shape. If the cutting edge of the knife is already round and the knife need to be sharpened to perfection, the power of 1000 grit whetstone may just not be enough.
I recommend choosing the coarsest stone possible to include in your kit. It may well be between 180 and 400 grit, and you can jump straight from there to a stone with a grit of 1 000. The coarser the stone, the quicker the knife can be repaired. I prefer stones between 180 and 220 for sharpening dull knives, but a 400 stone is often enough.
In almost all my Whetstone Packs I have added two essential accessories: a stand/holder and a whetstone.
The holder makes Sharpening - especially learning to sharpen - much more straightforward. It is more comfortable to rotate the stone and get it in the correct position, and at the same time, it raises the stone above the work surface, giving your hands much more room to work.
In addition, the obligatory accessory of a leveling stone is on everyone's list of must-haves. Unfortunately, in almost every workshop in Finland, you can find grinding stones that are either evenly u-shaped or utterly hollow in the middle. This is because, at one time, leveling stones were not sold at all.