04-08-2021, 07:45 AM
Hello, I have some new findings.
KnifeGrinders asked: "Have you started thinking of a de-rooting method in your sharpening process?"
Yes, I did. De-rooting at the Victorinox Knife (# 3.9050) was done at an angle of 2° above the previous sharpening angle with the 12.000 Naniwa Superstone which was moved only with the cutting edge. After 3 - 4 diagonal pulls, each about half the length of the blade, the other side was processed and this was done 3 times for each side. Finally, the blade was stropped a few times over cotton fabric. After this procedure, no scattered point reflections could be seen on the foremost cutting edge under a microscope with 60x magnification. The visual impression was now the same as with Werner's knife and the cutting force with the BESS thread was in the same range. The cutting edge angle is 30° this time (same as Werner used) and no longer 20°.
In order to be able to recognize any micro-dent, photos were taken: An old 24 mm wide-angle lens from Tokina with a Canon FD connection was attached to a Sony full-frame camera using a retro adapter and 3 intermediate ring sets (150 mm in total, lined with black D-c-fix velor film on the inside). This results in a 7.5 times magnification, i.e. 4.67 mm of an object are mapped onto the 35 mm sensor width. Since the sensor has a width of 6000 pixels, object structures down to a minimum of around 780 nm can theoretically be displayed. This means that the physically possible limit (Abbe limit = light wavelength) is almost reached.
After 5 cuts through the BESS thread, a spot can clearly be seen on the blade. The cutting forces increased only slightly, but continuously: 108, 109, 115, 120 and 121 cN. The red point (Edding pen) was used to find the cutting position under the microscope and for the photos.
Back side of the blade. The spot can be seen clearly too. And there is definitely no micro-dent. Maybe a nano-dent below the resolution limit.
I think the increase in cutting force is also related to how rough the grinding is. Except for the foremost front edge (0.05 mm or so), my grinding is significantly smoother than Werner's.
KnifeGrinders asked: "Have you started thinking of a de-rooting method in your sharpening process?"
Yes, I did. De-rooting at the Victorinox Knife (# 3.9050) was done at an angle of 2° above the previous sharpening angle with the 12.000 Naniwa Superstone which was moved only with the cutting edge. After 3 - 4 diagonal pulls, each about half the length of the blade, the other side was processed and this was done 3 times for each side. Finally, the blade was stropped a few times over cotton fabric. After this procedure, no scattered point reflections could be seen on the foremost cutting edge under a microscope with 60x magnification. The visual impression was now the same as with Werner's knife and the cutting force with the BESS thread was in the same range. The cutting edge angle is 30° this time (same as Werner used) and no longer 20°.
In order to be able to recognize any micro-dent, photos were taken: An old 24 mm wide-angle lens from Tokina with a Canon FD connection was attached to a Sony full-frame camera using a retro adapter and 3 intermediate ring sets (150 mm in total, lined with black D-c-fix velor film on the inside). This results in a 7.5 times magnification, i.e. 4.67 mm of an object are mapped onto the 35 mm sensor width. Since the sensor has a width of 6000 pixels, object structures down to a minimum of around 780 nm can theoretically be displayed. This means that the physically possible limit (Abbe limit = light wavelength) is almost reached.
After 5 cuts through the BESS thread, a spot can clearly be seen on the blade. The cutting forces increased only slightly, but continuously: 108, 109, 115, 120 and 121 cN. The red point (Edding pen) was used to find the cutting position under the microscope and for the photos.
Back side of the blade. The spot can be seen clearly too. And there is definitely no micro-dent. Maybe a nano-dent below the resolution limit.
I think the increase in cutting force is also related to how rough the grinding is. Except for the foremost front edge (0.05 mm or so), my grinding is significantly smoother than Werner's.