Honing placebo effect

[KrstGor]

So... males' facial hair ranges from 40 to 150 microns in diameter.

When we talk about DMT sprays, pasted balsa progression and what nots... with 0.5 / 0.25 and ultimately 0.1 micron how in the world would that have any effect whatsoever on smth. that is anywhere between 200 to 1500 times larger in diameter?

Scientifically nothing supports the claim that that kind of micro "teeth" on the blade would significantly diminish / improve its cutting ability.

Imagine trying to chop off a 100 year old Oak tree with a pocket knife. Does it really matter what grit you've honed the pocket knife on?

Maybe I'm missing smth. here.

 

[stone and strop]

Imagine trying to chop off a 100 year old Oak tree with a pocket knife. Does it really matter what grit you've honed the pocket knife on?

If it were always sharp, it could be whittled down. It would take a very long time.
If it were really dull, it would not be possible.
Sharp matters.
I believe there is an end point though. Anything around 10k and up can shave very comfortably. Hell even an 8k very well done can be very comfortable and close.
Many get carried away with grit numbers for some reason.

 

[KrstGor]

If it were always sharp, it could be whittled down. It would take a very long time.
If it were really dull, it would not be possible.
Sharp matters.

Sharp matters indeed. It's just that I don't see how this 0.1 would improve anything. It's negligible.

 

[alla2465]

pastes are not for everyone, I personally only use it to refresh an edge.
Who cares about the "science" if you like it, use it, if you don't like it, don't use it.

 

[stone and strop]

I do not use pastes and will never. I do not need to.
I don't see the point in using it to that degree either.
To each his own.

 

[LJS]

Size of hair, micron of pastes, these numbers have nothing to do with some non-existing equation for shaving. Good refined edge will shave better and finer abrasives help do that. It’s not theory. How you get there is not all that important but does impart some “flavor”.

Paste etc can work great. And you can do great without them.

Try and see for yourself. They have been used for centuries so it’s not just a theory or wive’s tale. Or don’t

 

[SliceOfLife]

The diameter of the hair is less relevant to the sharpness of the tool required to cut it than the make up of the hair, the way the hair is suspended, and how closely you want to cut to your skin.

Hair is held up right essentially by being pinned in the follicle... Shaving is cutting something that is flexible and only being held on one side of the location of the cut. This requires a certain level of sharpness for the blade to easily penetrate the hair and pass through without deflecting it much and pressing it against the surface of the skin preventing a close shave. This is why people using dull razors have to pitch the spine upwards, by increasing the angle of approach you are deliberately pinning the hair against your face, this makes the shave more irritating and less close... but makes it much easier for the razor to penetrate the hair and cut it.

Once a razor is honed to the point where it can shave smoothly without pitching the spine, Then you are attempting to increase the sharpness to allow the razor to cut more instantaneously Once in contact With the hair with the goal being that the hair not deflect at all during a shave, though this is impossible... it’s the ideal.


Diminishing returns has nothing to do with razors reaching a point where being sharper is not an improvement. It has to do with the limitations of the steel meaning that at some point the edge Can no longer survive the shave at the level of refinement you took it to... and the edge fails and degrades immediately upon use.


So there is sharp enough... then as sharp as you need or like... and eventually the limitation of how sharp it can be based upon the geometry Of the blade and grade of the steel as well as the shavers technique.


This is going to vary between different honers, different razors, and different shavers

 

[Steve56]

You’re looking at it the wrong way.

When I select a finishing stone (I don’t use pastes either), I select it on the basis of how smooth, close, and comfortable the shaving edge is. If it’s a natural, they have no assigned grit so one cannot worry about it. If it’s a synth, almost anything 10k and up is quite good, but some make better feeling edges than others, like naturals you just have to try them.

How well the edge suits you from any finishing medium is the only thing that matters.

 

[rbscebu]

It's the quality of the shave that counts, nothing else. That may also include a psychological component.

I have a few identical SR's and have shaved multiple times using them off 1.0um, 0.5um, 0.3um, 0.25um and 0.1um. In order of shave quality for me (worst to best):

0.25um & 0.3um
0.5um
1.0um
0.1um

Scientifically I cannot explain, all I know is that is how it works out for me.

 

[RayClem]

Sharp matters indeed. It's just that I don't see how this 0.1 would improve anything. It's negligible.

That was what I thought as well until I purchased a bottle of 0.1 micron CBN. When I first tried it, I was skeptical that it would have a noticeable affect, but I easily noticed the improvement. I have a really tough beard and really sensitive skin. I cannot say that the 0.1 micron strop made my edge significantly sharper than 0.25 micron CBN, but my face could easily tell the difference. Although I could shave without uisng the 0.1 micron strop, I would never want to do so.

Some guys say they can shave using a blade honed on an 8K Norton. My first finishing stone was a 12K Naniwa and it did not produce an edge that I could use. It was sharp, but far to harsh on my face. I now use a Suihiro G20K hone which goes down to 0.5 micron, but I still get better shaves if I follow up with my CBN strops, ending at the 0.1 micron level. Folks whose beards are not so tough and whose faces are not so sensitive can probably get away without using pasted strops at all, but I appreaciate the difference they make in my shaves.

 

[global_dev]

You’re looking at it the wrong way... How well the edge suits you from any finishing medium is the only thing that matters.

I've been shaving the last couple of days off a Chosera 3000 edge "finished" by a Zulu grey. It absolutely shaves well enough to be a real setup imho. I am really kind of surprised having not really enjoyed shaving off a 1K edge, but it shaved well enough, wouldn't call it a setup though. Would I call this 3K "base" my most enjoyable edge I ever have had the chance of shaving off? Absolutely not, those edges are just ridiculous and have no peer and you know it once you feel it.

 

[Gamma]

A .1 µm particle is roughly 50% smaller than a .25 µm particle. That is not negligible, it's significant.
Look at Shapton Pro stones, the 1.64 µm 8k is often followed by the 0.98 µm 12k, which is a 40% difference. Jumping to Chromox 0.5 µm from a ~ 1.0 µm finisher is in the same ballpark.

This is all academic though. In and of itself, partifcle size doesn't really mean much. An edge finished on .1 µm "Abrasive A" is not the going to be the same as the same edge if it was finished on 0.1 µm "Abrasive B".

Scientifically, a finer edge is a finer edge and it can cut 'better' than a less fine edge - the caveat is that other suitable criteria are must be met.
For example, it's not unreasonable to imaging cutting rope with an axe faster than one could with a razor. Diameter of the whisker isn't important, it's how tough is the material across its diameter. Technically, the razor is 'sharper' - but the material and task at hand matter. Which sorta relates to what Ian is referring to. I think so anyway.

Besides Ian's points of the hair and how it's held, there's a matter of celluar structure also. It all adds up to create a certain difficulty level for the edge in question. I would not rule dimension out as a factor entirely, but I would not position it as a key point of concern here.

In a perfect theory, an edge coming off .25 µm diamond would be "X" sharp. Same edge taken to 0.1 µm diamond would develop enhanced sharpness of "X" to an unknown exponential. In theory it is possible that the latter edge would cut better. It is also possible that the 'improved' edge would fail.
But, If the material remains constant, then edge enhancement up to the the point of diminishing returns can be a 'felt' improvment. This is contingent on the edge not becoming too thin/brittle for the task at hand though. Iwasaki spoke of barbers shaving with a burr or what I interpret to be a 'wire edge' - which can be very sharp but not smooth or long lasting. We need a 'true' edge, not a 'false edge'.

Instead of particle size being the focal point, remember that...

Abrasive type matters, Alundum is not the same as diamond, FeOx, or Chromox.
Particle shape matters, poly or monocrystalline diamond for example. They are not the same.
Particle density across the substrate matters. A lot.
Particle size distribution matters, even moreso at the sub-sub-micron levels.
Use of pressure matters, all aspects of the substrate matter, shape, size, flexible, rigid, etc.
The blade itself matters also. Not all steels respond the same way to the same abrasives.
How the blade was honed in the first place matters so much it's not funny.

I have an abrasive compound with a particle size in the 0.04 µm range. When used correctly on an edge taken to a suitable level of refinement, that compound will improve the edges. But if that edge wasn't done right in the first place, or the abrasive is used incorrectly, that edge will not improve.