Knife Sharpener Types: How to Choose What’s Right For You
By far, the most common question we get at Montana Knife Company is this:
“How do I sharpen my knives?”
On the one hand, knife sharpening is about having the right tools and techniques. On the other hand, it’s about understanding the factors that are unique to you, your knife, and how you use it.
But the first requirement for getting a great edge on your blade is simple — you have to start with a good knife.
The wrong edge geometry, steel, or heat treat will all prevent you from getting the strong edge you’re looking for. So starting with a quality, well-made knife is crucial.
From there, we can get into the tools and techniques you actually use for sharpening.
Types of Knife Sharpeners
There really isn’t one, go-to sharpener that knife owners should always use above others. You can find great products in each of these sharpener categories. Which you choose will depend on your needs and your preferences.
Oil stones are a type of whetstone that’s generally on the harder side. They wear down more slowly, and while they tend to be more coarse, they come in a variety of grits. If you’d like a little toothier edge to your blade, an oil stone is a good option. It’s important to remember that you can only use oil stones with oil — never with water.
Water stones tend to be on the softer side with a finer grit. They’re often used to sharpen chef’s knives since they can produce a nice, high-polished edge. Unlike oil stones, water stones don’t leave oil residue on the blade.
Diamond stones last a long time, work quickly, and are used dry. If you need to sharpen knives made with harder steels, the more aggressive diamond stones are a better option than oil or water stones. However, they can be expensive.
Electric sharpeners work very fast and can remove a lot of steel, but because of this, it’s hard to get a precise, fine edge. We find that electric sharpeners often remove too much steel from a nice, thin blade, ultimately shortening the life of the knife.
How to Choose a Knife Sharpener
Let’s look at a few important factors that will help you choose the right knife sharpener for your needs.
First Factor: Weight of Stone and Size of Blade
Before going out and buying a stone, think about how you plan to use it.
Do you plan to set it up at home on a workbench or bring it along in your pack? What size knife do you plan to sharpen with it?
If you’re out hiking or hunting, you’ll want a stone that’s small and portable. You might only need it to touch up the edge of the hunting knife you’re using frequently on a trip.
If the sharpener will sit on your bench at home, or if you need it to sharpen large chef’s or hunting knives, you might think about getting a bigger stone.
Second factor: Frequency of Use
Determining how much you plan to sharpen your knife will help you decide how much to spend on a stone.
Do you plan to sharpen your knife once a year, after hunting season maybe? Or, do you have a chef’s knife that you use every day and need to keep incredibly sharp?
If you’re sharpening your knife daily or weekly, you need a quality stone that won’t wear down quickly. High-quality stones like diamond stones are expensive, but they might be worth the investment depending on your line of work. If you’re sharpening a hunting knife one to three times a year, though, you probably won’t see much wear and can go with a less expensive option.
Third Factor: Condition of the Knife
Consider a few questions about the condition of your knife before determining how to sharpen it.
Was the knife made properly?
Unfortunately, a lot of knives simply aren’t ground to the proper edge geometry when made. If that’s the case, the knife will have to be sharpened first with a coarser grit to take off more steel, then finished at a finer grit to sharpen a new edge.
What kind of steel is your knife made with?
Softer stones won’t cut hard steel as well as a diamond stone or a good oil stone. For this reason, it’s important to consider the hardness of the stone compared to the hardness of the steel in your knife.
For example, an S90v knife would be much tougher to sharpen on a soft stone than one made with 5160 spring steel.
How thick is your knife?
This is a question of how much steel needs to be removed from the blade in order to achieve a sharp edge with the right geometry. The answer to this question informs the grit of the stone you choose. If it’s a thick knife, you might need two or three stones of varying grits to work your way down to a good final edge.
Stay Sharp with MKC
MKC offers several combinations of sharpeners on our website that work well with our knives. From small field sharpeners that fit in a pack to large bench stones, they’re great for sharpening everything from coarse hunting knives to fine chef’s knives.
The honest truth is that every kind of whetstone is just a tool to help you maintain your knife. Again, the most important factor in achieving a strong edge on your blade is to make sure you get a knife that was made correctly from the start, with good edge geometry and proper steel and heat treatment. All too often, people end up with knives that are impossible to sharpen well because they simply weren’t made properly.
Ultimately, we suggest MKC knife owners mail in their knives to us, and we sharpen them for free. This ensures your blade gets experienced attention and a great edge every time.
If you want to learn how to sharpen your own blades, take a look at our video on how to sharpen a knife correctly, in which I share good sharpening principles and offer demonstrations.
by Josh Smith, Master Bladesmith and Founder of Montana Knife Company