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Originally Posted by AFDavis11
The cutting pattern we replicate on a stone creates striations on the edges of each side of the bevel of the razor. These striations, when aligned properly help cut the whiskers of the beard. They need to oppose each other to be most effective. They are the base structure of the fin or cutting edge.
Since the edge hasbevels, it's the termination of the striations at the edge (or the plateau between them) that produces the teeth we call the fin. I have seen them in high magnification electron microscope shots of a knife edge (if any one is interested, I'll find and provide the URL to the site).
The goal in all knife sharpening is to create the sharpest edge. That comes with the finest striations and accounts for the improved cutting of a coticule honed edge as compared to an 8K. The coarser stones produce teeth which are less sharp (don't cut as well) but hold up better because they have a stronger physical structure. In sharpening, there is always a tradeoff between the sharpness of an edge and its durability. It's no different with razors. The easier cutting associated with a sharper edge comes at the price of having to refresh it more often. It's the reason a Feather DE blade will cleanly remove your whiskers with no force, while an incompletely sharpened str8 will be rough and leave a lot of hair on your face.
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So, I believe the three characteristics your searching for in an edge for say a medium beard are a balance between sharp, smooth (the literal edge itself remains unbroken microscopically) and striated. For fine beards I'm certain that striations probably have little effect.
I don't accept that the heavier striations are necessary for anything but robustness. With a heavy beard they may be indispensible, because the edge would otherwise be too weak, much like a wire edge. But for any other beard, sharper is better, up to the point where you begin to weaken the edge too much. We have infact experienced this from our work with finer pastes, yet the edge preoduce by a .25 paste (100K) is not too weak for most shavers.
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If you follow the X pattern or a heal leading stroke and keep the angle correct during the stroke the striation pattern created can help a little in cutting whiskers (more so with a heavy beard). You can create a finer and finer edge and the finer you go the less important the striations become because your honing into an edge as sharp as a DE and it cuts purely on edge sharpness.
This is where I disagree. Every edge cuts on edge sharpness. The sharper, the better it cuts. It's basic physics and a common principal of sharpening. Note that the treatise looks at the thickness of the edge (literally sharpness) as a figure of merit. I totally agree that coarser striations will improve durability of the edge, but we need to keep the concepts of sharpness and durability separate. If you're willing to work a lot, sharpness will always cut better. BTW, smoothness and sharpness are inseparable, because the finer striations always produce a smoother edge. But there has to be a limit where we can feel smoothness (of the bevels), while the sharpness of the edge continues to improve, which also gives the impression of greater smoothness.
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Once you understand the relationship striation actually has on cutting ability it helps to understand other "odd" phenomenom like why a pyramid method works on honing. Leaving a striation in place with a low grit pass, then smoothing for 3-5 passes on a higher grit, makes much more sense once you keep the striation pattern in mind (in my opinion).
I'm not sure this explains it at all. Larger striations cannot make the edge sharper ro smoother, just more durable. The mixed grit honing gives you fine teeth interspersed by large grit spaces, kind of a serrated pattern. But serrations don't cut smoother. They cut certain types of surfaces, like meat, better (by tearing). A hair is not that type of surface. I think the large grit phenomenon is simply expalined by the fact that it reduces the number of swipes. After the high grit pass you can continue to hone with increasingly finer grits and you will not lose sharpness, but increase it.
Are you saying that and edge with interspersed fine teeth will cut whiskers better than a continuous edge with the same teeth? I don't think there is any evidence for that or that it makes a lot of sense.
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It may also explain why some very experienced honers can get a razor to cut effortlessly on almost any rock, even as low as 8k and others need nothing less that .25 paste.
I think this is explained entirely by experience with a particular hone. Some guys have so much of it with the 8K that they can get very fine results. Others have come to rely on the pasted strop and can't get those results with just a hone.
