With all the sarcasm, I can't tell if you are purposefully being obtuse or if it just comes naturally to you. But it's worth pointing out for the others reading and might have an open mind that the knives aren't "ruined" permanently. A sharpening (wet) will expose fresh undamaged metal.
Further, no one said the edges are "ruined", just that they are not optimal. (It's a straw man argument to say take "dry sharpened edges are sub-optimal" turn it into "all dry sharpened knives are ruined!". Nice try.)
First of all, keep personal attacks out of a discussion. I did not say anything derogatory to you. Yup, there was sarcasm, because I find the entire idea redonculous and I like goofing with words. Also, at no time was my response directed at you since you just restated the info, you did not invent that theory. It is mainly directed at Landes comments. Don't take it personally. I am glad you brought it up and I think it is worth discussing. I do not for one second believe dry sharpened knives are sub optimal at all. And as of yet, there is no physical proof of this. This is how redonculous this is that the melting temp of standard steel is 1500 degrees Celsius, 500 DEGREES Below landes comment below. So in other words someone hand sanded an edge of steel to 500 degrees Celsius above it's melting point and recorded it with tiny little thermocouples that apparently did not melt with it. Why didn't anyone challenge this in that thread? Without further explanation of how an attached thermocouple measured temperatures above the melting point of steel while attached to the molten steel, the entire test is worthless.
Here is more of what he said
I had a book dedicated to general grinding methods, in this book i found a test application.
A normal steel block apx. 2"x2"x4" that had a large number of highly sensitive thermocouples integrated in the surface.
The block was slit dry by hand over a 1000grit grinding paper.
The peak temps measured, walked up to 2000°C for split seconds in the very surface (some microns).
He is basically interpreting results done by someone else. How fast was the block being ground into the sand paper? was it very fast in order to create heat or was it slow like how you should sharpen? What kind of steel was it? Plain carbon steel? or alloy steel? Big difference in thermal properties between the two. Was the steel heat treated? or not? Big difference there as well. I fully understand what he is saying. I will not argue that the potential of a burned edge is there with belt sanding. I do not for one second believe that hand sharpening will cause edge damage of any kind. I stated from the beginning that it is my opinion. I did do a search last night and I did not find one thread where someone proved this theory correct. Just a lot of talk. The OP in that thread put thermal paint on the edge and not even the very tip of the edge discolored to the 400 degrees with the 320 belt, effectively giving an argument that goes towards disproving Landes comments.
Here is another actual test done using thermocouples. It is basically a steel part ground with a grinder spinning at 19ft/second. A load of 2kg was applied. Unlike a slack belt, a grindng wheel has no give. So a 2kg load on a grinding wheel is considerably more force than what someone applies to a slack belt. Regardless, a good example. The maximum temp attained was 720 degrees Celsius. This is a good argument for being careful when using a belt sander. 720 degrees is a far cry from the 500 degrees above melting point attained by Landes.
So we have a guy on BF that did a test with a belt sander and did not exceed 300 degrees celsius. Then we have another test with a grinding wheel that reaches a temp of 720 degrees. My conclusion(to myself) as of now is that dry hand sanding is safe and will not cause temps anywhere near half the temp listed by Landes on a knife. I state a knife because Razors were mentioned and are very thin steel. I could see the thin steel of a razor getting hot enough to ruin an edge on a belt sander. But by hand? I don't think even a razor could sustain thermal damage by hand.
I honestly wish more knife makers were vocal instead of so much silence on certain subjects. Every large production manufactured knife comes with a machine sharpened edge. If the hand applied edge is suboptimal, then the machine sharpened edge must be ruined. This is what I meant. I wasn't trying to change your words.
I hope this explains my point of view and my opinion.
