Thread: Scratch pattern catalog?

Has anyone ever compiled images of scratch patterns from popular hones so one could look at them and compare one to another? I know synthetics have grit/micron ratings but I think it would be neat if someone took a polished piece of metal and did X amount of strokes on each stone and published the results. Does something like this exist? I did that with some unknown stones I had laying around and under magnification I could see if one was finer than the other. I know natural stones really wouldn't fit in here due to variability but I'd take that data too. Look at me talking like this actually exists and that someone will turn up any minute with a URL :-)

If that doesn't exist, then surely a massive chart with all the popular stones rated in microns must exist?

I think you want something like this:
JapaneseNaturalStones.com: The Big Test

but I don't think natural stones are as simple as just giving them a grit rating... I'm sure someone who knows more than me will chime in and expand on that

Yes it does exist in many places

It is also the cause of much misinformation

Let me explain with two pics


Same Chalk Same Surface Different pressure ..







So unless it is done using uniform steel blocks with uniform pressure under pretty strict conditions it means little to nothing

Which means that every one with a USB has taken the shots of various hones and SR bevels and made basically any claim they wanted about Hones in general and Natural stones in particular

ie: Misinformation but defended vehemently by those making outlandish claims

Indeed, a single stone can give a wide range of results. I'm still learning but beyond pressure I'd add condition of the stone surface, slurry vs plain water, water vs glycerine or oil depending on the stone. I was also thinking about variation between stones that are nominally the same material because there's no uniformity in nature.

Good explanation Glen. Thanks for showing the differences.

I've done this for years with a single razor. Same scope, same blade angle, same lighting angle and intensity etc. Don't have a website though, just pics saved to my hard drive. Don't make any "outlandish claims" either.

I never have liked that chalk analogy personally. Steel and chalk don't share enough of the same properties for that to be worth a whole lot IMO. It would be quite difficult to apply enough pressure to a piece of steel to get it to crumble for instance.

I did an unscientific test a little earlier because my coti's softness is really putting me off. Its not that I don't like it, its actually a fantastic piece of rock to hone on but I was expecting it to produce something in between an 8k and 12k. Anyway, I rubbed the coti and a 4k and 6k synthetic against my test piece of steel for 30 strokes with equal amounts of pressure and under the scope the coti looked like it could have been 300 grit compared to the scratch pattern of the other two. The synthetics produces some polish and I got none from the coti. I don't have a complete set of similar stones that I can do a full proper progression with. You could say I'm still in the collecting/acquisition phase since I'm coming from knives. Was sorta hoping that the coti would have been closer to 8k but not the one I have. I wanna do a proper progression so I can use my new escher properly :-)

I actually really do like the pair of chalk photos. No, chalk is not remotely analogous with steel, and I don't really care about crumbling.

To me, the take home point of those photos is that the same hone can produce different results depending on how it is used.

Heres the Naniwa superstone progression