Thread: A magnified comparison of many honing results

[QUOTE=Jimbo;891844why don't we try debating the actual thing itself? For example, are any of Glen's points invalid? If so, why? [/QUOTE]


I agree

So in the spirit that the thread was intended, allow me to comment on those pics.

I have seen these before some time ago. I believe Zowada posted them here at SRP when he did them actually, IIRC. First, stating the obvious, one side does not a sharp edge make. These are magnified pictures of one side of an edge of one razor, and if I needed proof of which of the actual honing media Zowada owns gives me a nice side of an edge of one of his razors under those lighting conditions, angles, part of the blade, specific microscope, day, water type, atmospheric conditions, etc etc. I need look no further than these glorious pictures.

Yes, I know I am being heavy-handed here, but what does one replication on one day tell you about anything? Would you infer the efficacy of a drug for the entire population based on a single experiment of its effect on one person on one day? Of course not. And I for one do not see why we should not try to apply a similar level of rigour to what we do, or at least make people aware of lack of rigour and its implications.

Don't get me wrong, I think that this kind of exploration is excellent and potentially quite useful, and I would encourage continuing endeavours along these lines - it is all more data, after all. But as it stands it is very inconclusive and rather ambiguous.

James.

I think Tim did an excellent job of making the lighting as consistent as possible for these pictures. Of all the microscope pictures I have seen here (my own included), these seem to be the best for consistency.

Maxim did something like this too and he compared many finishing stones.
Was good, but the light angle or something was different between a few
pictures. Sometimes the bevel was very shiny whereas in others it was like
there was very little reflection.

Sharpman

As a new guy, seeing the pics was nice, but hearing all of your opinions on it was what made it value added.

I think that everyone will agree here, when we are talking about natural stones, even synthetics, between two stones of the same type, be that ohira, C12k or thuringian, the edge they give vary a lot. For thuringians, coticules and C12k their estimated grit may vary between 8k to 15k. For the ohira between 5k and 50k etc etc. Looking at one picture of one razor honed on one stone will not bring you closer to the holy grail of the ultimate edge.
The other thing I have observed is, there are some slate type hones like yellow lake or everkeen. When I hone with them with water, they give what appears to be a mirror finish, and the edge magnified looks very fine. And they shave fine. When I switch them to oil, the scratch pattern worsen, but the feeling while shaving improves. What you see under magnification is not by far a guarantee that you will have a pleasant shave.

Originally Posted by Gammaray

I often use a 10x and 20x loupe to check the bevel during honing. But can never really see the edge which when perfect disappears from view.

My college science classes help me to appreciate that light microscope images like these are tricky to obtain. These are very nice depictions of the bevel and edge, albeit from one side. An electron microscope is even better. The Complete Guide to Sharpening by Leonard Lee confirms results similar to these optical images. The electron microscope revealed that the 8000 grit followed by CrO was near perfect on chisels. Yes, the woodworking guys are almost obsessed with sharpness as we SR guys.

These and other images confirm that there is a difference in the results expected from various stones. However, I bet in experienced hands most can yield good shaving results. I for one welcome more objective evaluation of blade sharpness. Thanks for sharing Lynn.

Im fairly new to straight razors honing but experienced in the woodworking sharpening for many years,you can put a mirror finish on a chisel even a dollar store chisel but it wont last long, the same on a Witherby will last, but they will look the same.
So once again the pic are cool but to many variable, the more and more im into honing the only way is to test shave.

Once again, I'm late to the party... Please don't make more out of these photos than what they are:

This is not meant to be a definitive study of the honing qualities of various stones. Rather, it is just meant to give me a basic idea of what's going on.

I originally posted them because I thought they might be useful to someone else. I've learned a lot about microscopes and edges since then. Mostly, that you need at least 1000x to really see what is going on, in terms of whether the edge will be a good shaver. That is getting in to electron microscope territory. Especially if you want good photos.

Lynn is right, the best and easiest way to decide what you like is to shave with it (my paraphrase).

Someone, with good technique, can make a fantastic shaver with an 8000 grit hone. Nerds, like me, like to tinker...

Tim Z.

Fortunately, posting thes pics did as I intended. They sparked healthy debate. I may be a new guy but I do research and I don't take things for granted. The pictures were enough to help me decide to get even more information. I mentioned this same quote when I posted.

This is not meant to be a definitive study of the honing qualities of various stones. Rather, it is just meant to give me a basic idea of what's going on.

Tim my apologies I did not get your permission before posting them.
I still enjoyed them Thank You. :-)

Mr Tim, I have to ask, where did you find this Chinese stone from the photos? Seems a bit finer than most of the Chinese hones out there.