Pasted Strop Part 1 shows the difference nicely. I think that the foil edge would be thinner if he used Matrix stones instead. Either way I think this light foil edge will come off nicely with a strop. I just left a message for him to see if he would be interested in trying out the Matrix pass-around kit, I would love to see what difference he could see with these stones with his SEM.
First photos in
post 23 show some difference I experienced going from bidirectional to edge trailing only after reaching the apex.
I inherited a single lens microscope from a doctors office, father in law was an MD among other things. It is nothing special but after I got a USB camera that fits in the eyepiece it works very well. Taking photos to look back on is much better than trying to remember what you saw 20 minutes ago. I have been told that a stero microscope is multitudes better but $$$$, I was also told you get what you pay for here and Mitutoyo's are really nice. What I have is good enough to see .0005" microchips in the apex so I am happy enough for now.
Belief changes-
Biggest is edge trailing vs edge leading but some of that has to do with the resin bond stones I developed, the Matrix stones. The diamond is super sharp and will cut with virtually no pressure, something I needed the microscope to understand. Even though it doesn't feel like it they are doing their job with no pressure. Just for the record not all resin bond diamond stones are the same, the Venevs need pressure to cut, they don't cut with light pressure, and leave a much bigger burr. I think this is a hugh deal. It is interesting to see what a leather strop or denim strop - my pant leg, will do to the scratches left on the bevel. It is interesting to see how just a few strokes will smooth the edges of the scratches. Steel at this scale behaves differently than we are used to. Add a little diamond to the strop and wow it can round the apex is just a few passes. Most of the time you want a bare strop.
I used to micro bevel everything but have since done it less. If the workpiece is abrasive or I am sharpening my one ceramic knife I don't micro bevel. I can not put a micro bevel on my Kyocera ceramic knife without microchipping the edge, period, no can do!!!
The apex will lose it's strength over use, don't just refresh the edge too many times. For best results you need to grind it back to expose fresh steel when you sharpen. My main kitchen knife is a Henckels 7" santoku, 16 degrees with a 21 degree microbevel. To maintain the edge I would just refresh it with a few passes at 21 degrees with the 4k stone. I started noticing microchips in the apex, the older the edge the more it would microchip with refreshes. When the steel is fresh I have no issues with microchipping.
Early on when sharpening with the finest Matrix stones, mostly the 4k, I would notice stray scratches in the bevel that I couldn't figure out, this was with edge leading passes. At first I thought it was contamination but it didn't make sense because I would still get them after freshly dressing the stones. When I looked at it under the microscope I noticed the scratches pointed to microchips in the apex. What was happening is the apex would microchip and the chip was causing the scratches. I changed to edge trailing passes and not only did the scratches disapear but so did the microchips.
I think the biggest advantage to edge trailing strokes is how the abrasive enters the steel. With an edge trailing pass it gradually enters going from the primary grind to the bevel, a difference of just a few degrees, with edge leading it enters abruptly going from air to a sharp edge. I think this puts much more stress on the apex, which is increadibly delicate. I think the sharpness of diamond exagerates this and that plated diamond tools would be the worst for edge leading passes. This is just an idea I have formulated from a fair amount of observation.
Enough for now, got to get to work.