10-31-2018, 01:18 AM
(This post was last modified: 10-31-2018, 01:38 AM by KnifeGrinders.)
The more I think of it, the more you seem right, Steve - it can't be that simple as rounding.
All my honing methods are controlled-angle, yet I clearly see the same pattern.
I think it surprises us only because of the wrong vision of the edge apex we have. Thinking of apex as something zeroed as a corner of triangle, it will sure surprise that the sharpness depends on the edge angle.
But in reality the apex has a finite width, a minuscule but width, which is dragged against the abrasive grains.
When the edge is put perpendicular to the honing surface, the whole width of the apex gets abraded. Suppose we hone at 45 degrees - then only half of the width is abraded, and so on, the lower the angle, the less is abraded area.
With the edge at 90 degrees to the honing surface the apex dulls, while at 0 degrees nothing happens; the closer to 0 the better goes refining, while the closer to 90, the more is dulling.
Especially in the microscopic scale, the apex honing runs in a subtle balance between refining and dulling through abrasion.
What do you think?
Continuing along the same path of reasoning, what practical conclusion comes? So how can we get the 10 dps sharpness on a 20 dps edge?
By decreasing the size of the honing grains, I suppose. The sharpness we get on a 10 dps edge by honing on chromium oxide, on a 20 dps edge will require 0.1 micron diamonds/CBN and even lighter pressure. But when using the same chromium oxide on 10 dps edge and 20 dps edge, the 20 dps will never get the same sharp, because its apex gets comparatively more abrasion.
Makes sense?
All my honing methods are controlled-angle, yet I clearly see the same pattern.
I think it surprises us only because of the wrong vision of the edge apex we have. Thinking of apex as something zeroed as a corner of triangle, it will sure surprise that the sharpness depends on the edge angle.
But in reality the apex has a finite width, a minuscule but width, which is dragged against the abrasive grains.
When the edge is put perpendicular to the honing surface, the whole width of the apex gets abraded. Suppose we hone at 45 degrees - then only half of the width is abraded, and so on, the lower the angle, the less is abraded area.
With the edge at 90 degrees to the honing surface the apex dulls, while at 0 degrees nothing happens; the closer to 0 the better goes refining, while the closer to 90, the more is dulling.
Especially in the microscopic scale, the apex honing runs in a subtle balance between refining and dulling through abrasion.
What do you think?
Continuing along the same path of reasoning, what practical conclusion comes? So how can we get the 10 dps sharpness on a 20 dps edge?
By decreasing the size of the honing grains, I suppose. The sharpness we get on a 10 dps edge by honing on chromium oxide, on a 20 dps edge will require 0.1 micron diamonds/CBN and even lighter pressure. But when using the same chromium oxide on 10 dps edge and 20 dps edge, the 20 dps will never get the same sharp, because its apex gets comparatively more abrasion.
Makes sense?
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