Sharpening: wet or dry?

On a related note Woodworking magazine has an article testing 1/2in chisels this month. An interesting test of edge holding was to measure the sharpened edge with a profilometer, simulate use by using a standard load to cut against oak, then remeasure the edge. The Japanese chisels tended to hold up well, and the Sears did surprisingly well on edge holding but the handles were kind of funky. An interesting test method though, which didn't correlate with the measured Rockwell hardness or cost.

I tried dry sharpening with a new Arkansas stone and while it seemed to cut quicker initially it also loaded up pretty quickly. I prefer using oil with an Arkansas stone, and also will usually strop on some leather to finish up.
 
I would expect these results for a power hone. The forces are higher and faster. I would think you would have a risk of sort of hammer-welding particles into the edge region if you don't have cooling and lubrication.

The issue for me is what to do by hand? By hand you use slower speeds and more controlled pressures. Usually you're willing to take longer and can deburr as you go along. I favor wet as the more reasonable approach. I am not trying to abrade the edge by simple friction, I am trying to cut off material using the sharp corners of my abrasive. My machine shop experience is that a lubricated metal cutting tool works better, lasts longer, and generates less heat in the cut region.

Over the years there have been several "experts" who assume that there understanding of the funtion of the edge is superior to generations of tool sharpeners who have gone before them. They assume that they know what a sharp edge is supposed to look like under a microscope and that by comparing microscopic images they can tell which method is superior. They frequently leave out the practical testing of the finished edges in real world tasks. I liked the inclusion of such tests in the article at the beginning of this thread.

My experience as a semi-professional sharpener is that the edges I produce from a wet or oiled stone cut better than the edges I have gotten with dry stones. I don't know why and I think speculating the reason at times highly colors your observations.

I prefer to hone under running tap water to insure zero loading of my hone and zero heating of my edge. I do some finish strokes on ceramic rods which may be dry or wet. These are removing a very small amount of material. I clean the rods often with abrasives to keep them unloaded.
 
The observation I'll make is that the article deals with sharpening chisels and woodworking tools whose use is exclusively pushing cutting (shaving) vs slicing.

If knives were sharpened the same way, they may be prone to be excellent shavers but perhaps lousy slicers.
 
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