I just posted this msg in my 'Apex Bevel Geometry' thread in another forum. It could be a fun read, so I copied-post here:
I spent considerable amount of time on the physics & visualization of sharpening grind interaction -> I gave up (more like deferred) for now, since who the heck want to read this dissertation anyway (ok, maybe a few of ya).
Alright then, booted myself back to Keep-Simple principle.
Sharpening stroke direction - edge trailing or edge leading or combination? I found a while back (re-invented the wheel - only sharpmaker is the purist) that edge leading stroke worked better than trailing/stropping stroke. Here is an easy experiment you can easily replicate.
Used DMT 6EF to de-burred: Used light pressure strop strokes for edge-trailing sample. Used light pressure edge-leading strokes for edge-leading sample.
I don't have a SEM & SW (to construct field depth) to give a good edge/apex facing view. Just to show that 'Edge-leading 90* deburred' edge is clean and thinner than 'Edge-trailing'. I am not going to blah about variables this & that at play.