Overheated edge BESS scores

[KnifeGrinders]

I think that there is a lot to be agreed with here. Common sense and experience has shown me that lots of pressure on high grinding speeds and coarse abrasives can turn an edge blue in fairly short order.  Also makes sense that the idea of dipping a ground edge in a bucket of water may be like closing the barn door after the horses have escaped. It makes sense that slower speeds, less pressure and finer abrasives should also add up to less risk of detempering but I'm not convinced though that detempering edges is the real problem or that slow grinding on a stone solves that problem. When someone shows me that stone ground edges roll 50 or 70% less  than belt ground edges then I'll be a believer.I don't think to date that the tests run have shown anything like those kind of improvements. I may be feeling my oats a bit here and I'm not saying it may not all be true but none of this has been proven, that detempering with belt grinders is the problem or that hand or very slow grinding solves that problem, to my satisfaction yet. Having said all that I will tell you that this discussion is a good one and I appreciate all points of view and opinions.

I love this forum because we do tests. We don't rely on the opinions of self described experts here. I'm not from Missouri but I act like I am, so please, "show me". When you do, I'll thank you for your time and work and if you can't I'll still thank you for your time and work.

When in the SET test a copper roller is used instead of the steel, the 1425 RPM edges roll by 56% worse than Tormek-deburred.
Using a softer roller in SET testing magnifies the differences in edge holding during the elastic deformation phase, making them readily observable.
It takes 100 copper rolls to deform the edge to the same extent that the steel roller does in the first 5 rolls.



It is clear from both our plant trials and the SET test numbers that, even though overall worsening of edge retention in high RPM edges may not be huge, the peak worsening happens when the edge is the sharpest - edges compromised by high RPM honing lose the initial sharpness quicker, i.e. transit quicker from the initial elastic deformation to the irreversible plastic deformation.
This is exactly what our butcher noticed: "the knife #2 [Tormek-deburred] initial razor sharpness lasted longer"

In simple terms, it matters for very sharp edges.
If your knife application does not require lasting sharpness of < 200 BESS, you can ignore these differences, but now it will be a well-informed consensual ignorance.