The Lansky has four sharpening angles:
- 17 degrees
- Recommended for razor blades, fillet knives and similar tools.
- 20 degrees
- Recommended for kitchen cutlery and slicing knives.
- 25 degrees
- Recommended for hunting and outdoor knives.
- 30 degrees
- Recommended for cardboard, wire and carpet cutting knives, and other heavy duty blades.
The sharpening angles aren’t accurate
The Lansky’s angles aren’t accurate. Two factors determine the sharpening angle. These are:
- The blade’s width.
- The blade’s placement inside the knife clamp.
I’m no mathematician, but let me explain the hypotenuse concept as best I can.
The Lansky, with the honing stone and guide rod in place and resting on the knife, creates a triangle. They call one side of that triangle, the one represented by the honing stone, the hypotenuse.
The hypotenuse is
the longest side of a right-angled triangle, opposite the right angle.
On the Lansky, the hypotenuse is the length from the knife’s edge to the edge of the hole through which you stick the honing stone extension.
The further you move the edge, or the wider the blade, the longer the hypotenuse becomes. This changes the sharpening angle.
To further complicate things, the Lansky struggles to accommodate a long blade. There’s a big difference between the honing angle closest to the knife clamp, and the honing angle at the point farthest from the clamp. This shows best on longer blades.
But you won’t mind these shortcomings once you see the difference a sharp blade makes.
True sharpening angles
To determine the Lansky’s true sharpening angles, I measured two knives while they were clamped in the Lansky. One’s a steak knife, the other a chef’s knife.
Note: These calculations aren’t rock solid. I don’t have digital measuring equipment. I own a standard vernier caliper and ruler. The purpose of this exercise is to show you the difference between angles a small distance makes, not to give you exact scientific data.
Here are the specs…
|Chef's knife||Steak knife|
|Cutting edge length||188mm (7.40 inches)||115mm (4.53 inches)|
|Shortest right angle length||130.8mm (5.15 inches)||110mm (4,33 inches)|
|Longest right angle length||188mm (7.40 inches)||136.4mm (5.37 inches)|
|Blade's width (at widest point)||41.4mm (1.63 inches)||21mm (0.83 inches)|
|Hypotenuse - 17 degrees - shortest angle||132.5mm (5,22 inches)||112.5mm (4.43 inches)|
|Hypotenuse - 17 degrees - longest angle||190mm (7.48 inches)||139mm (5.47 inches)|
|Hypotenuse - 20 degrees - shortest angle||134mm (5.28 inches)||114mm (4.49 inches)|
|Hypotenuse - 20 degrees - longest angle||191mm (7.52 inches)||140mm (5.51 inches)|
|Hypotenuse - 25 degrees - shortest angle||135.8mm (5.35 inches)||115.8mm (4.56 inches)|
|Hypotenuse - 25 degrees - longest angle||193mm (7.60 inches)||141.5mm (5.57 inches)|
|Hypotenuse - 30 degrees - shortest angle||138mm (5.43 inches)||118.8mm (4.67 inches)|
|Hypotenuse - 30 degrees - longest angle||194mm (7.64 inches)||144mm (5.67 inches)|
Note: Do not clamp your knives as I did in the pictures below. I did it to make a point, not for sharpening.
Here are the sharpening angles for these knives, based on the specs above.
|Lansky angle slot||Chef's knife sharpening angle||Steak knife sharpening angle|
|17 degrees - shortest distance||18.38 degrees||24.2 degrees|
|17 degrees - longest distance||16.64 degrees||22.2 degrees|
|20 degrees - shortest distance||25.09 degrees||30.45 degrees|
|20 degrees - longest distance||20.34 degrees||26.04 degrees|
|25 degrees - shortest distance||31.19 degrees||36.42 degrees|
|25 degrees - longest distance||26.14 degrees||30.86 degrees|
|30 degrees - shortest distance||37.18 degrees||44.38 degrees|
|30 degrees - longest distance||28.57 degrees||37.4 degrees|
Sharpening at the right angle depends on more than the markings on the Lansky.
Yet, this does not make the Lansky a bad tool. It’s close enough. The knives I sharpened at these angles work well.