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You pretty much just described the Knife Deburring Book... may want to look at that.

Thanks for that. I bought it.
This is the best thing I have read so far. To my taste, the author jumps a bit too much from topic to topic (and back again), but if you write it down in an orderly fashion, it would be exactly what I'm looking for at the moment.
Best, Robert.
 

... I would offer one suggestion. In my opinion, a bench chisel is the the ideal tool for studying sharpening with a Tormek....

Hello, Ken
Thanks for the idea, but as I'm a strange guy, I'm interested in understanding the problem first and then finding a practical solution.
I've been sharpening woodworking tools and knives for almost 50 years and I can do it reasonably well.
But what still puzzles me, or frustrates me, is that I don't know really what I'm doing - or more precisely: why I'm doing it this way and not another way (well, its  stems from a mix of trial-and-error, good advice ... and not so good advice).
I am interested in a theory of the formation of ridges, their typology and then their practical removal.
Many thanks, Robert

Hi, many thanks.
I just had a look at science of sharp.
Absolutely mind blowing pictures; however the author is very cautious about drawing generic conclusions.
I like his careful approach, but personally I am more interested in a descriptive model of burrs:
how they emerge, can be detected & classified and, lastly, can be removed.

[Is this how the burr comes to existence in spine-to-edge grinding?]

Thanks, John,

"... the steel will deform as the grit passes over the edge and form a burr as the steel edge "turns up" opposite the edge exposed to the grit ..."

Okay, forming of the burr (spine-to-edge grinding):
the steel is pushed by the grinding wheel, thus gets somehow a little bit more liquid (temporarily) and 'flows' from the inner edge to the apex; like the butter which is more liquid/deformable than he bread is smeared to the fringe of the bread.
Once the liquidized steel has reached and passed the apex, it forms an initial burr.
As more steel is deformed and pushed over the apex it agglutinates with the already existing burr and makes it bigger.
The burr is very thinly connected to the edge (at least as thin as the apex); therefore the pushing from the wheel bends it to the other side of the the edge.

Is this how the burr comes to existence in spine-to-edge grinding?

Hi everyone,
I am new in this forum, so forgive me if I ask stupid questions.
I tried to find answers for my questions, but maybe not looking in the right place.

After almost 50 years of sharpening knives I still struggle with the concept of the *burr*:
(i) Assume one sharpens from the spine to the edge of a knife: the wheel causes an abrasion of the steel; as the abrasion 'rips out' tiny particles of metal, some of the steel will get smeared in direction to the edge (like butter on bread) and forms a tiny lump - the burr.
(ii) if the knife is turned to the other side (still spine-to-edge), the same occurs. Why is there not another burr from the other side? There is only one burr - is it the agglutination of two burrs? As there is no thermic forming because of the low speed and the water cooling, how can this happen?
(iii) Assume grinding from the edge to the spine of a knife:
assuming the butter-on-bread assumption in (i) is correct, there shouldn't appear a burr on the edge but instead maybe something more in direction of the spine. BUT there IS a burr at the edge!
(iv) This seems to imply that the butter-on-bread-smearing analogy is wrong for edge-to-spine grinding (at least). But where does the burr then come from? Is it metal that is pressed by the turning wheel 'over' the apex of the edge such that it agglutinates on the other side?
(v) If this would be true, we would have two different types of burr - at least from their origination (and possibly to be corrected by differing procedures) ...