10-16-2021, 08:23 PM
Welcome to the forum hardheart!
Please consider that the following is just from my own experience…
Anything around 100 is very sharp. Congrats on those edges! Unless the goal is making razor blades, 100 is plenty, if not sharper than necessary. The thing to remember is that the sharper an edge is the thinner it is. 100 is extremely thin. It does not take much to dull it. A thinner edge is more susceptible to rolling and will dull more quickly. 150 or 200 works great for general use blades. Anything sharper will quickly change to that range with little use. That said, while the blade is still super sharp it’s cool.
Take a freshly sharpened blade that is ~100 and then chop a few carrots or potatoes, etc. Then measure the sharpness again That 100 edge does not last long.
It all depends on the use. If slicing sashimi with no blade to cutting board impact is the use, the sharpness will last a long time, but with anything with resistance or cutting board impact super sharp blades will dull 50-200 points very rapidly.
If a burr has formed after grinding from both sides and the burr is completely removed I would always suspect 80-150, with 150 being on the high side. From your description of how well you sharpen I would suspect burr.
When using a microscope, lighting is everything when it comes to visualizing a burr. Use a flashlight or other directional light. Move the light in all directions; from the top, edge on, spine to edge… every direction. It makes a huge difference. From some directions the burr can completely disappear. But when it’s right the burr will reflect light. Experiment with the direction of the lighting. It makes all the difference in the world.
Try dragging the edge at 45 or close to 90 degrees to the edge across the leather on both sides of the blade. This will bend the burr and hopefully fatigue it off. Then do it again at sharpening angle to straighten and clean things up.
For me at least a guided system works best. I’m not that good at freehand. I use a Kalamazoo 1SM and a Kallyrest. Generally edges turn out 100-120. But… chopping a few carrots and they soon turn 150 or more. Just depends on the blade.
I hate it when an edge does not get as sharp as is seems it should. Generally, IMHO, burr has been the reason.
Please keep us informed if you do/or do not figure it out!
Please consider that the following is just from my own experience…
Anything around 100 is very sharp. Congrats on those edges! Unless the goal is making razor blades, 100 is plenty, if not sharper than necessary. The thing to remember is that the sharper an edge is the thinner it is. 100 is extremely thin. It does not take much to dull it. A thinner edge is more susceptible to rolling and will dull more quickly. 150 or 200 works great for general use blades. Anything sharper will quickly change to that range with little use. That said, while the blade is still super sharp it’s cool.
Take a freshly sharpened blade that is ~100 and then chop a few carrots or potatoes, etc. Then measure the sharpness again That 100 edge does not last long.
It all depends on the use. If slicing sashimi with no blade to cutting board impact is the use, the sharpness will last a long time, but with anything with resistance or cutting board impact super sharp blades will dull 50-200 points very rapidly.
If a burr has formed after grinding from both sides and the burr is completely removed I would always suspect 80-150, with 150 being on the high side. From your description of how well you sharpen I would suspect burr.
When using a microscope, lighting is everything when it comes to visualizing a burr. Use a flashlight or other directional light. Move the light in all directions; from the top, edge on, spine to edge… every direction. It makes a huge difference. From some directions the burr can completely disappear. But when it’s right the burr will reflect light. Experiment with the direction of the lighting. It makes all the difference in the world.
Try dragging the edge at 45 or close to 90 degrees to the edge across the leather on both sides of the blade. This will bend the burr and hopefully fatigue it off. Then do it again at sharpening angle to straighten and clean things up.
For me at least a guided system works best. I’m not that good at freehand. I use a Kalamazoo 1SM and a Kallyrest. Generally edges turn out 100-120. But… chopping a few carrots and they soon turn 150 or more. Just depends on the blade.
I hate it when an edge does not get as sharp as is seems it should. Generally, IMHO, burr has been the reason.
Please keep us informed if you do/or do not figure it out!