Sharpening tools

 Here is an opinion, and observation. The opinion is mine, and I claim no expertise, though I have been sharpening and using woodworking tools for more than 30 years. If you find it TL;DR then suffice it to say "honing is your friend", but otherwise read on.

I think sharpen might be the wrong word. There are several things that you do to an edge of a cutting tool. Most of them are simply referred to as sharpening and that throws off the concept of frequency.

1. (Profile Grind) Upon receipt of tool one should "grind" it to their preferred profile for that tool. This would be done on lower (more coarse grits for faster cutting). Sometimes over the course if its lifetime a tool is repurposed and will be reground to a different profile in order to perform a different task. Doing this frequently will greatly reduce the life of the tool, and because of this some people will invest in multiple tools of the same design and maintain them with their preferred grind profile. Some tool makers create double ended tools, and I suspect, this is the main attraction to that design.

2. (Bevel grind) Once a profile has been established, it is unnecessary to revisit #1 again unless the tool becomes severely damaged (like dropping it on the concrete floor, or running the cutting edge into the chuck jaws  ) Other than in the cases where the profile is so severely altered, the more frequent thing, that I would call bevel grinding. This fully establishes a working bevel, with one single facet down to a fairly sharp cutting edge. This would be done at a finer grit and follow the established profile from #1. This may actually be the final aspect of sharpening for some users. Turners especially will go from this level of sharpening back to the work, as they may do this back and forth multiple times during the process of turning something.

3. (Refresh grind) If you use a tool from the bevel grind, you might simply return to doing a quick touch-up following the existing profile and bevel grind to bring the edge back into the shape you had from #2. It can be a light pass or even a higher grit (which will effectively do a lighter pass, think of golf where a 2 iron being the lower grit, and a 6 iron being the higher grit. Same effort goes a shorter distance).

In certain tools, a micro bevel may be added, this reduces the amount of area that needs to be sharpened to keep a keen edge, and essentially mimics the benefits of a hollow grind.

4. (Keen grind) This is where the edge is brought to a shaving sharp edge. This may never be necessary for some usage of a tool, but for others it is required. This could involve progressing through progressively higher grits and honing and polishing an edge to mirror finish and the requisite demonstration of accomplishment of shaving some area of the body (forearm or calf area), which leads to walking around with patches of bald flesh on your arms and legs giving you the appearance of having mange 

5. (Stropping/Honing/Steeling) Once the profile, bevel, and a keen edge are obtained, a tool may be used until the slightest sense that is is not quite as sharp as it was is detected, and one returns to a polishing mode (the last stage of #4). This can be done with very high grit such as "thousands" of a waterstone, extra fine on a diamond plate, polishing paste on leather, canvas, or MDF, or simply the hardened steel of a "steel" or even the spine of a hardened blade. Once you have an established keen edge, you may return to honing many times before it is necessary to revisit any of the above steps.

If you have a high quality blade possessing a high hardness such as RC62 it should certainly cut many things that are not as hard without having to renew the edge. One must consider spinning items (work or blade) are cutting much more than what appears in a shorter period of time. They are cutting literally "miles" of material. And most if not all material, though softer than the material of the blade, will have environmental inclusions, mineral oxides, or in the cases of certain woods like palm, will even include silica as it is absorbed during growth. As these things "wear" down a keen edge, there is also the aspect that the edge gets rolled over especially with highly acute angles like those used in things like carving tools, and straight razors. When this happens, the honing/stropping/steeling action works to either straighten the tiny thin edge back to a cutting edge, or works it off like the wire edge burr that occurs during the sharpening process.

So if you watch some carvers like Mary May they may make a few cuts with a gouge then stroke it on the leather strop make some more cuts. And when it gets to very precise detail aspects, may return to the leather "just in case". When you see them return to a diamond plate or water or oil stone, the time spent there is minimal, limited to minutes if not seconds refining the edge back to keen. Likewise watching turners like Mark Silay, he has a small stone or diamond plate that he will quickly hone up the edge of his gouge either as it "feels" less than keen or he otherwise deems necessary. It is a quick process to see him do it, but is all that is needed for him to proceed with his task. I have a block of wood with 150 sandpaper glued to it. When I grab the Stanley utility knife from the drawer to go out and break down all the amazon boxes I hit it a few strokes on each side and I can fit all the boxes into my recycle bin, just as easily as if I put a new blade in. And if it is post xmas (with lots and lots of boxes), I might bring the block with me in my back pocket and hit it again as it feels less surgical.

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