Thread: Cotis v Japanese Naturals v. Guangxi: A single-blind, repeated measures experiment

Defenatly going to be an interesting read

It's almost 1AM, and I'll post the results tomorrow. But I want to make sure no one misinterprets the nature of this post.

A better title might have been MY Cotis v. MY J-nats v. MY Guangxi. This is not meant to be a "which is best" experiment. Although I've tried to eliminate as many variables as I could, there are two things I could not control for.

First, all these stones are natural, not man-made. I'm convinced that individual variations exist among Cotis, J-Nats, and even the People's Hone. Maybe the examples I have are not the best finishers of their type; the odds that I have the superlative Coti, the finest J-Nat, and God's Own Guangxi are one in several billion.

Secondly, I could not control for me. I believe I was able to impartially rate the closeness and comfort of the edges produced. But I've always been partial to Cotis, and J-Nats are relatively new to me. Maybe my honing skills leaned toward one stone rather than another. I tried to use the same strokes, the same pressure, etc., but I recognize the results might have been different with a different hand on the blade.

In short, I think that the results should not be generalized across all stones of these types, or across all honing skill levels. I wanted to know which of MY stones, in MY hands, currently gave me the best edges, so that I could produce the best possible shaves FOR ME. Maybe the only real contribution I'm making here is providing a template that others might use to determine what is THEIR best hone to produce THEIR best edges on THEIR razors.

BTW, Hot Tub Time Machine is pretty gross, but also funny. Anyone offended by the F-bomb should leave it alone.

Here let me summarize it for you,,,,

No matters the steps you might take to make it as scientific as possible, it actually never can be...

So in the venerable words of the Founder of this forum "Have Fun"

I also look forward to your results... all these types of experimentations help the overall knowledge base...

Shave On !!!!

Originally Posted by gssixgun

Here let me summarize it for you,,,,

No matters the steps you might take to make it as scientific as possible, it actually never can be...

So in the venerable words of the Founder of this forum "Have Fun"

I also look forward to your results... all these types of experimentations help the overall knowledge base...

Shave On !!!!

Well said.

I was intrigued when pcb01 mentioned his knowledge of experimental design but, no offense intended, disappointed at the described strategy. However, I absolutely appreciated his point of the two things for which he couldn't control. I think part of the fun of naturals is that each of us can cling to the certain knowledge that our own rock is much better than anyone else's rock!

Originally Posted by gssixgun

Here let me summarize it for you,,,,

No matters the steps you might take to make it as scientific as possible, it actually never can be...

So in the venerable words of the Founder of this forum "Have Fun"

I also look forward to your results... all these types of experimentations help the overall knowledge base...

Shave On !!!!

Agreed. A true experiment would be reproducible across different observers and, as I noted above, different observers might have different observations.

And it WAS fun!

This is one that RayG and I did last month that was a kick

http://straightrazorpalace.com/honin...aving-fun.html

And still as good as we tried, it had predictable results once the "givens" were known...

Given that RayG hones his own razors on a Coticule
Given that I use a Coticule for finishing on Sheffield steel

He chose the one with the Coticule as the best for his face..

But it was still fun

To review, comfort and closeness scores on each individual blade on a particular hone could reach a maximum of 8 and 16 points, respectively, and the highest possible score for any one blade in a rotation would therefor be 24. The scores were averaged across razors for each hone (i.e., ratings were added together for the four blades honed during different rotations on the C12K, on the Asagi, etc., then divided by 4 to get an average of the stone's performance on the four blades). Hope that's clear.

Hone Comfort Closeness Combined

La Veinette 7.25 14.44 21.69

6X2 Coti 6.5 13.8 20.3

Asagi 7.13 13.13 20.26

Asagi-Kiita 6.88 14.5 21.38

Guangxi 6.75 13.19 19.94

The most comfortable finisher was the "La Veinette" Coti. As I mentioned earlier, I did feel a distinct comfort level from this stone toward the later rotations, although I did not identify it as the "LV" until the end of the experiment, when I looked at the key. So my subjective experience matches the results. The Asagi also gave extremely comfortable shaves, yet somehow different. I never mistook it's finish as a Coti.

The stone that provided the closest shaves was the Asagi-Kiita, with "LV" being a close second. All my ratings were to some degree subjective, and there may not be a significant difference between these stones in terms of closeness.

The LV gave me the best combination of closeness and comfort, again followed closely by the Asagi-Kiita, and again a result that might be reversed if I did the whole thing over again.

While the overall averages fell short of perfection, there was one superlative shave: the Dovo finished on the LV reached a score of 23.5, near perfection. Honorable mention goes to the Grelot (also finished on the LV) and the Wosty finished on the Asagi-Kiita, to both of which I gave a score of 22.5; also, the Grelot finished on the A-K (22.25).

The worst shave. Interestingly this was again the Dovo, finished on the Asagi. It was comfy, but scored (by far) worst in terms of closeness. Overall, I gave it an 18.5

So there were some real surprises for me. My "finishing" 6X2 Coti was mid-pack. My LV, which Bart felt would be great for me to do initial work on, turns out to be a great finisher. In an email, Bart confided that in the past stones from this source sold at a 50% premium over other cotis because they had a knack for removing metal. I hope I understood him correctly. At any rate, maybe history garbled the message: maybe they were highly valued as finishers. Or maybe I have a very unusual one. As I said earlier, I was very suspicious of this rock when I used it early in a progression: it was reluctant to make slurry, very slow to set a bevel, etc. NB: Bart himself never used this stone; he saw it at Ardennes, and based on the "LV" reputation, had them send it to me

Am I going to sell the other stones and use the LV (or A-K) exclusively? Not a chance. My shaving and honing history is littered with items and products that were relatively worthless to me until I learned to use them properly, and I'm still learning the art of honing. There are slurries, progressions, alternative strokes, etc., that I want to experiment on with all these stones. And, again, J-Nats are new to me and I've loved Cotis for quite a while. Even though I did not know what hone had touched which blade, this may have affected the result. But at least I know what works for me most consistently at this stage and skill level. Maybe a year from now I'll be finishing on the Guangxi with a slurry of Crox, ruby dust, and dog spit.

Did I get my 2% improvement? Well, there's about a 9% difference between the lowest- and highest-ranking stones here, but the difference between the two highest ranking stones is only 1.5%, probably not a significant difference, with an unlikely large bout leading the way.

Thanks, Bart.

... for the data presentation above. It was in a table when created, but everything got scrunched in the actual post. Can anyone tell me how to fix this? Thanks.

Thanks for an interesting read, pcb01.

But Williams still sucks compared to the luxuries afforded by fine European soapmaking traditions Now excuse me, I have to entertain some beautiful women........

Originally Posted by Ryan82

Thanks for an interesting read, pcb01.

But Williams still sucks compared to the luxuries afforded by fine European soapmaking traditions Now excuse me, I have to entertain some beautiful women........

Just PM me if you need any help with either...