09-08-2017, 12:25 PM
If there is any detectible difference due to bevel angle, and EOU states that for all practical purposes there is not, it is insignificant when compared to the 20% variance of test clips. If variance exists, it is not even close to 20%.
In theory you may be correct Mr. Steve, and I had some of the same questions at first. One thing to consider however is that the impact of bevel angle on the sharpness reading is so miniscule as to not be detectible by the test apparatus so it is basically irrelevant.
Another interesting observation is that we are measuring knife and tool edges which are really big, clumsy instruments as far as edges go. Remember that EOU test instruments can measure differences between various DE razor blades, and our knife and tool edges are not even approaching the level of sharpness. Even if some minute variance were to exist cleaving test media due to bevel angle, and we were actually able to measure it, that data, while it might be intellectually entertaining would be of little or no real world consequence.
If I sharpen a knife and see a 20 gf variation along the edge I’m generally completely satisfied because I know I won’t be able to detect that variance when chopping some kohlrabi or a piece of rope and I know that after one cut the sharpness will decrease at least that much anyway.
I use the PT50B which has a resolution of 5 grams. It is nowhere near granular enough to begin to measure any possible influence of bevel angle cleaving the very small diameter test media.
That said, it is nonetheless certainly entertaining to consider exactly what is happening.
Over time I’ve gained total confidence in the equipment and sharpness readings even when it informs me that I just did a crappy job of sharpening or deburring!
In theory you may be correct Mr. Steve, and I had some of the same questions at first. One thing to consider however is that the impact of bevel angle on the sharpness reading is so miniscule as to not be detectible by the test apparatus so it is basically irrelevant.
Another interesting observation is that we are measuring knife and tool edges which are really big, clumsy instruments as far as edges go. Remember that EOU test instruments can measure differences between various DE razor blades, and our knife and tool edges are not even approaching the level of sharpness. Even if some minute variance were to exist cleaving test media due to bevel angle, and we were actually able to measure it, that data, while it might be intellectually entertaining would be of little or no real world consequence.
If I sharpen a knife and see a 20 gf variation along the edge I’m generally completely satisfied because I know I won’t be able to detect that variance when chopping some kohlrabi or a piece of rope and I know that after one cut the sharpness will decrease at least that much anyway.
I use the PT50B which has a resolution of 5 grams. It is nowhere near granular enough to begin to measure any possible influence of bevel angle cleaving the very small diameter test media.
That said, it is nonetheless certainly entertaining to consider exactly what is happening.
Over time I’ve gained total confidence in the equipment and sharpness readings even when it informs me that I just did a crappy job of sharpening or deburring!