>>2475746If you paid attention in maths in school you'd remember that trigonometry dictates how well this guide will work.
Take the three sides:
* angle guide height (that's half the total height, since it takes the blade in the middle (green)) = a
* blade height (red) = b
* part of the stone between the edge of the blade and the guide (black) = c
We also know that there's a right angle between a and b.
With that information we know that sin(alpha)=a/c , cos(alpha)=b/c and tan(alpha)=a/b . All three of these calculations work. Since a is determined by the guide and we can't really influence c, our biggest variable is b, the height of the blade. Thus every knife will get sharpened at a different angle, based on its height.
You can either just use the guide anyways, and create a new edge at the angle that the guide suggests, not use the angle guide and instead sharpen to factory angle, or sharpen at a whole different angle.
>>2475658 is also wrong, the guide guarantees a consistent angle, not a specific (correct) angle. 
