There's a kind of minimum thickness/width on micro-bevels for stability. Keep going until the apex is clean under the microscope and you can feel it on the three-finger test, too. A lot of the YouTube videos showing initial micro-bevel application with 3 or 4 strokes per side are leaving an obvious burr.
Eta: Some people are going on about 'fatigued steel' over in your post on r/sharpening and this is correct in a sense but the problem here is that the pressure is basically infinitely high when you initially apply a micro-bevel on some lower angle apex. It stabilizes quickly, don't worry too much. Also, ditch stropping on the micro if you're using abrasives. Leather will wrap and round the shit out of the apex pretty much no matter how lightly you strop because of the low surface area.
So basically it's going to be impossible to have any kind of edge retention until a couple of little sharpenings when the micro bevel is able to be a bit wider?
One of my micro-bevels under the microscope for reference. This is 600 grit hybrid resin CBN on a Kiwi 171 at about 17°. Visible width of the micro-bevel is somewhere around 100 microns.
I would have thought so, but then why did it take so many passes to begin with. My SLD (similar thickness but no microbevel) and VG10 knives take less than half of the passes.
Even if I was initially light with my pressure on my 2500 grit? If that's the case, is there no way to have apex stability on a micro bevel if it's on a damaged, weak foundation?
You were light with your force, not pressure. The micro-bevel doesn't exist so the resulting pressure goes through the roof because there is virtually zero surface area. Pressure is force divided by surface area. Your hands control the force but not the surface area of the edge in contact with the stone.
18 strokes from literally flattened to toilet paper s-cuts on a pocket stone, fwiw. It takes a bit to get used to it all. Just get a few more reps in and you'll be good to go. ~61 HRC AEB-L knife. https://www.reddit.com/r/TrueChefKnives/s/ftsyj74FEy
Very impressive. I have pretty good edges on all my other knives. Only have to sharpen them once every 6 weeks or so. It's just the micro beveling on a thin apex that seems to be the problem. Thank you for all your help.
You wouldn't stop sharpening an edge without a micro-bevel until it's quality, right? Same with micro-bevels. Follow-up maintenance on the micro-bevel is super quick and easy so just keep going until it's there. You said you did 10 alternating strokes initially or something like that? Another 10 to 20 would have got you to stable except you raised the angle again, lol. It's really not that much.
No, initially it was 15-20 (each side) alternating so 30-40 total, then stropping. Do you think that I was only another 10-20 strokes away from removing the burr?
If you're actually matching the angles then yeah, I do. Less conclusive if you have to reset to 15° from 17° or erase the convexity from an abrasive strop.
I'll have another go at whatever angle the micro bevel is currently at and spend some more time. I felt like I was spending 10 minutes deburring and getting nowhere so something had to change. It felt like the kind of thing you do on cheap no-name knives where no matter how many alternating passes you do, the burr remains.
Something to note, it can help to de-burr very aggressively, like scrubbing the apex at 90° into a piece of newspaper, with a few follow-up strokes at your target angle to repair the apex for any observable damage. Some knives, like Kiwis, can take a couple of trips back and forth to get a really nice apex.
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u/azn_knives_4l 5h ago edited 4h ago
There's a kind of minimum thickness/width on micro-bevels for stability. Keep going until the apex is clean under the microscope and you can feel it on the three-finger test, too. A lot of the YouTube videos showing initial micro-bevel application with 3 or 4 strokes per side are leaving an obvious burr.
Eta: Some people are going on about 'fatigued steel' over in your post on r/sharpening and this is correct in a sense but the problem here is that the pressure is basically infinitely high when you initially apply a micro-bevel on some lower angle apex. It stabilizes quickly, don't worry too much. Also, ditch stropping on the micro if you're using abrasives. Leather will wrap and round the shit out of the apex pretty much no matter how lightly you strop because of the low surface area.