Thread: Hones and Edges Under the Microscope

I just finished doing an initial study, with pictures. I thought some of you might be interested.

http://www.tzknives.com/razorhones.html

Eventually, there will be more, and better pictures.

Many thanks to Lynn, Howard, and Charlie, for letting me borrow their expensive hones.

Tim Z.

Wow - very interesting indeed. If I am reading your results right, optimal edge from a microscopic point of view at least, would be to use the Coticule with a slurry initially, then remove the slurry for the final final polish?

Si

Let me just say that I wasn't at all surprised by the performance of the translucent arkansas - that photo is similar to what I see in my microscope after using mine.

Edit: Also, you can see where the 15k Shapton is already overhoned (there's a chunk of fin missing) after only 10 laps. That stone is extremely fast.

Wow, I was surprised that the natural stones' scratch marks were so fine. Especially the Chinese waterstone and the translucent arkansas. And the spyderco ultrafine looks very smooth as well.

Tim,

This is fascinating. I've been finding that my coticule gives the best edges, too. Seems like people figured that out centuries ago without the benefit of modern technology. Amazing.

Would you be willing to conduct this experiment with some barber hones and pasted strop compounds as well?

Also, just curious: Do you feel the results are repeatable? Were these the only shots, or are you confident they're representative?

You know that we're still going to bicker over which hones are "best" ...

Thanks again,
Josh
The funny thing is that we'll still argue about which hones are "best."

Nice photos. From appearances of the finished edges I would say out of the naturals I'd go with a Coticle without slurry, an Escher with slurry, the Chinese without and a Translucent Arkansas for the smoothest edges. Some of the slurried edges look less desirable once finished but I am sure they cut much faster.

Were the slurries made with a matching stone in each case.....coticule on coticule, escher on escher to keep particle size similar?

Tony

Snip:
Would you be willing to conduct this experiment with some barber hones and pasted strop compounds as well?

Sure, as time permits. I'll be keeping the blade I used in the tests to use in the future.

Snip:
Also, just curious: Do you feel the results are repeatable? Were these the only shots, or are you confident they're representative?

I took five shots of everything. They really are pretty representative.

Tim Z.

Originally Posted by Tony Miller

Were the slurries made with a matching stone in each case.....coticule on coticule, escher on escher to keep particle size similar?

Tony

Yup.

Tim Z.

I've noticed similar results with my Tam O'Shanter hone (my only slurry stone) when I've used it with and without slurry.

Has anyone ever done any sort of experiment with smooth vs toothed edges to see which one shaves better? In general push cutting prefers smooth&sharp edges while slice cutting prefers a toothier but duller edge, but I'm not sure how reliable this is at the sharpness levels we're talking about here. The polished edges look prettier, but do they actually shave better?

One thing I have found with the really polished edges is I have a hard time getting nicked. If I make a mistake the blade seems to "stick" to the flesh and stops cutting before getting deep enough for blood. This weekend I managed to slide the edge lengthwise along my throat while reaching back between my stretching hand and my neck (I was using a 6/8 instead of my usual 5/8). This should have laid me wide open, but the razor stuck tight as soon as it broke the surface. I lifted it away and kept shaving, and only got a few drops of blood and the wife didn't even notice the cut until I pointed it out to her (it was completely healed and gone the next day). I was using my 6/8 Friodur that had been polished on newsprint; comparable cuts with edges finished on boron carbide or even chrome oxide have been much worse affairs.

Tim,
Nice work. Nice razors too!

If you need any barber hones for tests I have about 30 here including most of the "must haves".

Tony