Knife Sharpening with Abrasive Belts
One of the first things when determining the right grit for knife sharpening is to clarify what method of sharpening you’re talking about. Are you using a sharpening stone or are you using a belt sharpening? There’s a huge difference between the two and where a lot of the confusion comes from.
Grits used for sharpening with stones are usually anywhere from 500 grit up to 2,000 grit, or higher.
Sharpening with a belt, however, requires grits in a range from 120 to 400 grit.
Since AIS only sells abrasive belts, that’s what we’re going to focus on here.
Evaluate the blade to be sharpened
The first thing you need to do is determine the current state of the knife to be sharpened. Is it dull? Does it have any nicks or dings that need to be removed? How fine of an edge do you need/want?
Select a grit or grits
Now that you’ve got a target, it’s time to select a grit. As we said before, you’ll be looking for belts between 120 and 400 grit. Start with a lower grit if you have more material to remove or imperfections to clean up, then move up to a finer grit to get a finer edge on the blade.
Choose an Abrasive Grain
Four types of abrasive grains are commonly used in knife sharpening – Aluminum-Oxide, Ceramic, Silicon-Carbide and Zirconia-Alumina. Let’s look at each one:
- Aluminum-Oxide is commonly used for knife grinding because it cuts faster than other options and doesn’t load up with metal filings. It is friable enough that the grains break off to stay sharp longer.
- Ceramic abrasives give long life and fast cutting. They’re ideal if you’re finishing stainless steel, high carbon or hardened steel blades.
- Silicon-Carbide abrasives are tough and durable but are less commonly used for knife sharpening.
- Zirconia-Alumina is also strong and durable and offers fast speed and provides consistent results.
So, what is your deciding factor? For a lot of knife sharpeners, it comes down to cost. Aluminum-Oxide is generally the least expensive option. Ceramic, Silicon-Carbide and Zirconia-Alumina, all cost a bit more than Aluminum-Oxide, but if you sharpen a lot of knives, their longer life may make up for the increased cost.
If you’ve read this far you might be wondering which abrasive belt we recommend. Well, we’re not going to tell you to use a specific abrasive or a specific grain. You need to make the final determination based on your preferences and your experience. Try them all and decide which is best for the type of sharpening you do. Remember, when using belts, stick to grits from 120 to 400. You can go finer if you really need to polish the blade.
Last, but not least, remember to follow all safety precautions when using belt sharpeners.