I have been experimenting with an inexpensive digital microscope to see if I can get photos of the scratch marks made on the edge of a scythe blade by all the different whetstones I sell. I would like to be able to see how the different stones compare in their effects on the edge. I peened one of my older Fux Gartensense blades, to where the edge would deflect fairly easily when a thumbnail was pressed up against it. I could not capture the amount of deflection in the photo above, so you will have to take my word for it. It was a nicely peened edge, though not quite as thin as the one in the video. I wanted the edge to be thick enough not to get chewed away by the coarser stones.
Next I marked off 8 sections with some tape, and then I proceeded to hone each section with a different scythe stone. You can see photos of the whetstones I used on my Whetstones page. I honed each section bench-style, with a diagonal, rolling, grinding motion, on the bevel side only, until each stone had raised a burr.. I removed the burr by honing on the back (underside) of the blade, honing towards the edge with the flat side of the stone, to cut off the burr without raising another one on the bevel side. Next I wiped all the sludge off the blade with a wet paper towel and then dried it with a paper towel.
Next I set the blade on a micrometer calibration ruler, and proceeded to try and take pictures of each section. The small lines in the scale are o.1 mm apart. The long lines are 1 mm apart.
Let's take a look. Below are the photos of the grit marks made by the whetstones, starting from the coarsest to the finest.
What can we conclude?
These microscope photos are a bit one dimensional. (Well, technically two.). I already know from experience which stones I think work the best. It is very difficult to photograph shiny metal edges to tell how sharp they are, but these photos do reveal the amount of tooth or scratch pattern, that they impart to the edge.