A Comprehensive Guide To Sharpening Angles -- Part 1
by James Lupton
If you want your knife to serve you well, then you will need to sharpen it. Although a seemingly simple task, there’s a lot more to sharpening your blades than just rubbing them over a stone. The angle you choose to sharpen at plays a pivotal role in determining how the edge turns out or whether the knife gets sharpened at all.
We have put together a comprehensive 2-part guide to add to your understanding of sharpening angles and to answer any questions you may have about the process or the angles.
What is a sharpening angle? It’s important to understand that most knives you find in the kitchen have a double bevel. And that when we talk about the sharpening angle, it means the angle at which “one side” of the edge is sharpened. So, if your knife sharpens at an angle of 20 degrees, the total angle of the edge will be 40 degrees.
How is the sharpening angle of the knife determined? Mass-produced knives get their sharpening angles determined by a device known as the goniometer. It essentially uses a laser beam, which projects the edge across a grid with various degrees on it, thus helping in finalizing the sharpening angle of the knife.
Accounting for variations in the sharpening angle: If you pick up a knife and it says that it has been sharpened at an angle of 20 degrees, it basically means that the knife has been sharpened at an angle ranging between 18 to 22 degrees.
When knives roll off the assembly line, they may look precisely the same (and in many aspects they are). However, when it comes to sharpening angles, they are often chosen manually and then the knife is sharpened by a skilled craftsman. So the variation in the actual sharpening angle is the result of the human element in the process.
In other words, sharpening your knife at 20 degrees is not a rule set in stone. So when it’s time to sharpen your new knife, you can start off anywhere between the range of 18 to 22 degrees.
There are rare instances when the manufacturer has to use an automatic, laser-guided knife sharpening systems to cope with the sheer volume of production.