Freehand on a 1000/6000 combination stone, maybe 15 degrees a side on a German chef knife. Straight off the stones it shaves and slices paper cleanly. Two days and about four dinners later it skates on tomato skin and tears paper. I strop on plain leather after sharpening. It feels like something is falling off rather than wearing out, since normal wear shouldn't be that fast.
Also possible you're being a bit hard on softer German steel. A 56-58 HRC blade at 15 degrees per side is a thin edge for that hardness, and it will roll. Try 17-18 per side and see whether it holds four dinners instead of two. Less impressive on paper, better on Tuesday.
Plain leather isn't doing much. Bare leather mostly aligns, it doesn't cut, and a wire edge that gets aligned by a strop is a wire edge that stands up nicely for a day and then falls over. Load the strop with a green compound or something around 1 micron and your after-sharpening strop actually removes the last of the burr instead of hiding it.
Worth adding: compound plus heavy pressure rounds the apex, which produces the same disappointment two days later. Light passes, edge trailing, maybe eight per side.
How are you storing it and what board are you on? Two days of dinners on a glass or a stone board will kill any edge no matter how well you sharpened it, and knives rattling loose in a drawer lose their apex on the drawer, not on the food. Wood or a soft composite board and a magnetic strip fixed half my 'edge retention' problems.
End-grain maple board, magnetic strip. So probably not that, but a fair question.
Sounds like you need a finer finishing stone, get an 8000 and it'll hold much longer.
Finer stones make a keener edge, not a more durable one. If anything a higher polish on a soft steel deforms sooner. The burr is the problem here, not the grit.
@whetstone_wu · 3mo ago · 3 replies
You're leaving a wire edge. It shaves because a thin flap of steel is sticking out past the apex, and that flap folds over or tears off after a few cuts, leaving you with a rounded edge that never was sharp. Fix is to stop chasing sharpness and start removing the burr properly: after your last 6000 passes, do 3-4 edge-leading strokes per side with almost no pressure, then a few alternating strokes, then check by dragging the edge lightly across your thumbnail at 90 degrees. If it catches evenly with no soft spot, the burr is gone.
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@burr_hunter · 3mo ago
The thumbnail test is where mine falls apart, there's always a section near the heel that feels different. So it is a burr thing.
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@whetstone_wu · 3mo ago
Then that section still has a burr hanging on. Work that spot alone with light alternating passes until it matches the rest, and don't move up in grit until it does.
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