Thread: CBN strops.... a thought

Originally Posted by eKretz

Progressing from a 1k to 20k took me about 15 minutes tonight. Here's the result:

I'm getting confused. The photos show an edge that has some rough spots to my eye. Isn't the objective to hone the edge so that there is a consistency in "smoothness" from end to end (which should result in a comfortable shave)? Why would you use a 1K in your progression if the edge does not need to be reset? I'm still learning, so please don't be offended by my questions that may seem simplistic.

Originally Posted by DoctorSaul

I'm getting confused. The photos show an edge that has some rough spots to my eye. Isn't the objective to hone the edge so that there is a consistency in "smoothness" from end to end (which should result in a comfortable shave)? Why would you use a 1K in your progression if the edge does not need to be reset? I'm still learning, so please don't be offended by my questions that may seem simplistic.

That is at 200x, any edge magnified that high will show all sorts of "rough spots" if the lighting is right. That's why I always take and post multiple shots with varying lighting. Many of the folks who use high magnification post shots with zero scratches, but that's only because the lighting is manipulated or just poorly directed to hide them. Rest assured, they are still there.

I could post a shot of that same edge with the light source moved to the right place that would make it look completely scratch free. I could do the same with a bevel finished on a 1k or 2k stone. The important thing is not that there are no scratches, but that they are very shallow - this is pretty clearly illustrated in the two shots above - the shot showing scratches is lighting aimed to bounce directly off the bevel and into the scope lens. The darker shot is raking light, which tends to emphasize and exaggerate scratch depth. As you can see, the scratches are almost nonexistent under raking light, which means that they are very shallow.

The edge depicted is very smooth in actuality. It is also directly from the stone, pre-stropping, and the taking light is aimed so that some of it bounces off the very edge, which is why there are some tiny white areas showing...this can give a good idea of relative edge width. You will learn over time that scope shots are not the arbiter that you think they are - at least if you start using your edges anyway. Some edges that look scary under high magnification can give absolutely fantastic shaves, and some that look very nice can give awful shaves.

Starting with too fine of a stone is a rookie mistake that can waste a LOT of time and effort. Higher grit stones do not remove much steel at all, so it is important to start with a coarser stone if there is any steel removal to be done. The higher grit stones are merely for polishing out coarser scratches. Once those coarser scratches are gone and the surface scratches are all from the finer stone they have a very tough time removing any more steel in a reasonable time frame.