Yesterday, 07:57 AM
(This post was last modified: Yesterday, 08:24 AM by WI_Hedgehog.)
(not related to medical or precision cutting instruments)
I agree the bevel angles are likely not equal and think the best way to do this is to mount the knife/blade in a quality fixed-angle sharpener and set the laser in a holder at the same height as the center of the holder. A flat scale can be fixtured/mounted behind the blade holder and then things are consistent.
I put a TSPROF K4 on a granite work surface so for me the setup would be fast and simple. Doing this with a Lansky sharpener would not be so fast or simple, but then again Lansky or free-hand won't hold an exact angle, so there's not much point in using an accurate measuring device on an inaccurate edge--for hand-held (or Lansky) sharpening "close is close enough."
Much less messing around is mouting the blade and using a marker to blacken the cutting edge, then use a polishing stone to find the angle that removes the marker. This works with a non-exacting sharpening method such as free-hand or Lansky. I like the marker method better because it can be used to show the defects/variations along the whole blade edge instead of one point and that's valuable with convex and non-consistant edges.
Variations in sharpening angle can come from inconsistent hold angle (like when moving across an edge to sharpen the length of the edge free-hand), short arms sweeping across a comparatively long blade (Lansky), or using multiple arms that aren't all at the same angle (Lansky). Convex angles can come from free-hand sharpening and similarly from fixed-angle systems that have movement to them, both causing multiple angles to be ground while sharpening resulting in a convex edge.
I agree the bevel angles are likely not equal and think the best way to do this is to mount the knife/blade in a quality fixed-angle sharpener and set the laser in a holder at the same height as the center of the holder. A flat scale can be fixtured/mounted behind the blade holder and then things are consistent.
I put a TSPROF K4 on a granite work surface so for me the setup would be fast and simple. Doing this with a Lansky sharpener would not be so fast or simple, but then again Lansky or free-hand won't hold an exact angle, so there's not much point in using an accurate measuring device on an inaccurate edge--for hand-held (or Lansky) sharpening "close is close enough."
Much less messing around is mouting the blade and using a marker to blacken the cutting edge, then use a polishing stone to find the angle that removes the marker. This works with a non-exacting sharpening method such as free-hand or Lansky. I like the marker method better because it can be used to show the defects/variations along the whole blade edge instead of one point and that's valuable with convex and non-consistant edges.
Variations in sharpening angle can come from inconsistent hold angle (like when moving across an edge to sharpen the length of the edge free-hand), short arms sweeping across a comparatively long blade (Lansky), or using multiple arms that aren't all at the same angle (Lansky). Convex angles can come from free-hand sharpening and similarly from fixed-angle systems that have movement to them, both causing multiple angles to be ground while sharpening resulting in a convex edge.