Beginner question about angles

[Craig Lison]

Please bear with me, I have always been very weak in geometry. :unsure:

On the Spyderco Tri-Angle Sharpmaker, there are two sides with stones that are inserted at angles. One side is labeled 40 degrees, and the other side 30 degrees.

However, in measuring the actual angles of the stones with a protractor or angle gauge, the 40 degree side actually has the stones at 20 degree angles, and the 30 degree side actually has the stones at 15 degrees.

What is the logic in this… I can’t figure it out. :blush:

[cbwx34]

I dont know if it’s the technical term, but the angle referred to when referencing what angle a knife is sharpened at, is often the “inclusive”,or total angle. So a knife sharpened at 40 degrees is the total… 20 degrees per side.

On the WE, since the angles are marked and set by the reference bar or angle cube, the angle referred to in the posts is the per side angle.

Edit: This is a good question btw… it trips alot of people up, so it’s helpful to define what’s being talked about.

[Author]

Posts