цитата:
The convexity near the apex is removed by the 4k level, and the measured geometry is unchanged with higher grits beyond the 4k. This result indicates that the bevel set is completed at the 4k level, not the 1k level as commonly believed. Beyond the 4k level, the bevel polish is refined and the edge width is reduced from about 0.3 microns to about 0.1 microns.
ПЕРЕВОД:
Выпуклость около вершины ( кромки ) удаляется при переходе на #4000
и измеренная (микро-)геометрия остаётся далее неизменной ( т.е. при переходе на более тонкие камни ).
Этот результат говорит о том, что формирование фасок (bevel set) завершается на #4000, а не на #1000 как обычно принято считать.
После #4000 улучшается отделка фасок и толщина кромки уменьшается с 0.3 микрон до приблизительно 0.1 микрона.
Как это выглядит и что получается на #1000 наглядно показано вот тут:
https://scienceofsharp.wordpre.../the-bevel-set/
цитата:
Sharpness is achieved during the bevel setting stage up to 4k grit. Beyond the 4k grit, Keenness improves, but Sharpness is not improved further.What this teaches me is explained very well by knife guru, Cliff Stamp (see Cliff's forum here):
' A low grit finish will generate a much thicker apex than a high grit edge which is one reason why a low grit apex will be stronger (resist lateral deformation) more than a high grit edge at the same micro-bevel angle. However the main issue is the type of cutting which is why I started with 'If they are slicing soft materials (cardboard, ropes, foods, etc.) :' . In this case the apex will typically not be under high loads to deform it, it will dull mainly from slow abrasion. To combat that, use a low grit edge to make an irregular surface which will take a lot of abrasion before it is worn smooth and stops cutting and use a low angle apex to both enhance the roughness and maximize the amount of wear required. Because the loads are small the angle you can use can be very low and there is no real risk of deformation.However if they are push cutting hard materials this type of finish won't work because the apex will come under heavy loads to try to deform it and if you use a low angle and finish the apex with a low grit finish it is very likely to collapse almost immediately. For example that finish in the above which easily slices though ~2000 piece of 1/2″ hemp will fail dramatically in less than 10 cuts if you try to push cut because the forces will be so high that the apex will just deform and can crack right off. In order to make the apex perform well under cutting that type of material you have to raise the polish and then increase the angle to prevent it from deforming. Now of course continuing to increase the angle past the point it stops deforming doesn't help. It is just that this point will be a lot higher in push cutting a hard material vs slicing a soft one.'
In other words, a coarse edge will have higher edge retention at very low angles when cutting soft material. I believe it will even have higher edge retention at the same angles as a polished edge, although a polished edge may excel in some push cutting tasks.
ПЕРЕВОД:
... продолжение следует ...
( переводить тяжело, так как я не улавливаю смысловую игру в противопоставлении sharp и keen )
в чём-то пересекается с идеей темы
forummessage/224/10
и даёт обоснованное объяснение того, что в ней описано.