Bevelled versus Rounded Edges for Narrow Hones

[Brontosaurus]

I have been using a set of narrow hones in the 35-40 x 130-135mm range. At present they are chamfered along the edges. Normally, I'm fine using them, but given their relatively small and narrow size, every now and then a stray stroke sort of flies off the honing surface and onto the honing edge as it were. I am wondering if rounding the edges, rather than chamfering them, might ameliorate the outcome when this occurs.

[bouschie]

Personally I would leave it and just slow down to avoid running off the edge.

[Utopian]

Rounding is better because it softens the contact during the mistroke. However, in either case you are risking edge damage because all the pressure is concentrated on a single point on the edge rather than along it entire length.

[Euclid440]

With a narrow hone, you can’t avoid running off the edge. I don’t think it matters much but I do give the edges a light rounding at the end of a quick lapping with the 1k side of a 400/1k plate.

You don’t need much, the goal of both is to smooth the corner and either should be done lightly, after any lapping. For a narrow hone or an X stroke, the edge is the last part of the hone to touch the edge.

[Brontosaurus]

Thanks all for your comments. I am aware that the goal is to never have this happen, the issue not being so much speed as its occasional inevitability. Very light rounding would seem to be a good way to go. But sometimes, the stone as received from the producer or seller already has a significant chamfer, so it's a matter of rounding the closest line there.

[Utopian]

But sometimes, the stone as received from the producer or seller already has a significant chamfer, so it's a matter of rounding the closest line there.

Exactly! You just want to round over that line between the honing surface and the chamfered surface.

[azourital]

+1 for rounding the edge

[Marshal]

Rounding is better because it softens the contact during the mistroke. However, in either case you are risking edge damage because all the pressure is concentrated on a single point on the edge rather than along it entire length.

Personally I would leave it and just slow down to avoid running off the edge.

These 2 pretty much sum it up. If you don't run off the edge, it won't matter if it's square, beveled, or rounded. I do prefer a rounded corner because it's more forgiving, but at the end of the day if the blade slips off the hone due to a miss stroke you're more than likely going to have to fix the damage you just did to it regardless of what the stone's corner profile is.

[Brontosaurus]

Just to clarify, it's not so much an issue of the blade or tip/toe running off the edge, but the blade lifting up at some point during the pass given the relative narrowness of the stone being used. The blade lifts up, and a point-by-point contact is suddenly made between the edge/bevel of the blade and edge of the stone, as Utopian has mentioned. The trick, I think, is how to arrive at a momentary steeling effect to lessen the damage should this happen. Rounding the very edge of the stone would seem to help in this case.

[kelbro]

I bevel/round all of my stones.