Thread: Same edge, same spot, same magnification, different light...

Originally Posted by Chris L

Bart, the gem here is your razor performance chart! I love it. I'll say that I think it should be a standard! Thank you for that.

You're welcome. After some serious pondering, that's what I came up with to keep track of the "double blind test"-results, but I find myself using it for assessing the results of unblinded honing experiments as well. Without saying that it should be mine, I agree that a standardized method for rating razor performance could be a meaningful addition to many conversations about honing.

Originally Posted by Chris L

I'm also pleased to see the rating #5 under Keenness "Hair breaks and falls silently" is EXACTLY what I've mentioned regarding my findings in levels of HHT and that IME a hair that responds in that manner has repeatedly yielded my sharpest edges.
So......HA!! That's two of us that have found this to be true. The shave test is the pinnacle test; however, the HHT IMO is NOT a parlor trick.

I couldn't agree more. For me, from all the predictive tests, the HHT comes closest to tell what I can expect during actual shaving.

Originally Posted by Chris L

One question for you. I don't do double bevels on razors or at least I have not yet. From what I've read and what I've done personally with chisels and micro/double bevels, IME it takes only a few strokes to establish an effective double bevel. Literally a few. What do you find if you do only 5-10 or fewer passes when establishing a double bevel?

I agree. The creation of a secondary bevel takes only very few laps.
BUT... (there's always a "but", isn't there?)

I 've come to think of honing in two different actions:
There's the action of refining. Making the point of the V thinner, sharper.
And there's the action of polishing. Removing the peaks of the scratch pattern on the surface of the V. At the same time this cleans up the meeting line of both bevel panes of our "V".

Some hones I qualify as both polishers and refiners. Once they 've hit the bottom of the previous scratch pattern, they just continue to emboss their own scratch pattern, hence refining the "V". They always max out at either a certain keenness level or a wire edge, depending on the hone itself.

Other hones I qualify as polishers only. They eat their way through a given scratch pattern, but one they approach the bottom of the pattern, they become too slow for any further "V" refinement. This is directly related to the decreasing PSI, as the contact surface enlarges. For that same reason, even a polishing hone can refine an edge when a few layers of tape divert all abrasive force to an extremely small part of the edge.

In practice with coticules, all this theory translates into the following (please bear with me, I assure you this is leading somewhere)

A coticule with slurry is a refiner, but, as we all know, it maxes out at an early level of shavereadiness.

A coticule with water is a polisher, one of the very best ever, but one without hardly any refining capabilities, hence the need for an already very keen edge.

I you force a coticule with water into a refiner, by using the secondary bevel trick ("diverting all abrasive action to an extremely small part of the edge"), it will refine the edge, BUT (here's the actual "but") at the same time this also introduces the maxing out issues of the coticule with slurry. Not entirely to the same extent, but still. The bottom line is that coticules have qualities as a polisher beyond the maximum sharpness you can squeeze of out a bare coticule induced edge.

For my experiment on the Dovo, I was not after the refining qualities of my Nakayama. (They yield about the same results as s secondary bevel, produced by my coticules). I used the Chosera 10K as a refiner and once the secondary bevel was wide enough, the Nakayama as a finisher.
On the Dovo, the final results gave me an easier shave than the same progression without the formation of a secondary bevel. (As stated before, my Dovo is notorious for that). The razor really went through the whiskers with less effort, most noticeably during the ATG pass.
If I was after testing a secondary bevel left by the Chosera, I would have stopped with 2 laps.

Let's just hope this still makes sense to you.

Best regards,
Bart.