Coticule edges (dilucot) under microscope 160x

Good day gens,

today I've received 2 small vintage coticules and have tried to compare them to other coticules I have.

Attachment 301613

From left to right:

• Lest Latneuses, hybrid side up
• La Veignette
• New grey coticule-BBW combo of unknown veign (any idea?)
• New shallow coticule-BBW combo, i believe its La Dressante
• La Nouvelle Veine

At the top right you can see a small jade slurry stone I have used on the coticules to create a slurry, so that each coticule is working with its own slurry.

For each coticule I've created the slurry of milky conistency and have done some sets of 10xhalf strokes with very light pressure. Didn't count the nr of sets exactly but stoped as I had a feeling that scratches of the previous stone were removed by the current one.
Then I've diluted by dipping the razor into a water glas after a set of halfstrokes. For smaller stones I've done more sets of half strokes, for larger - less. Again, didn't count the strokes but tried to go by feel.
Finaly 50 lightest possible strokes were performed on plain water. After each 10-15 strokes I've flushed the stone with fresh water.

OK, here the edges done with my optical microscop, the pictures are taken with my mobile phone through the objective.
Magnification is 160x.

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Some points on what I was reading out of the pictures:

• The width of overall scratches at the bevel indicates the size of the garnets somehow (e.g. La Dressante vs. les Lat/yellow).
• Some sporadic larger/deeper scratches may come from released garnets during/after dilution (auto-slurry).
• The brightness of the metal between the striations tells about the poolishing capabilities of on water, the darker the better polishing.

To me "La Nouvelle Veine" is a very good polisher but it releases its large garnets easily which leads to the sporadic deep striations and screw up the edge during the finishing phase.
The best finishing performance (but the slowest speed) was shown by La Dressante.
About the grey shallow I am not sure, it has a quite hard surface and seemed not to autoslurry at all. It even didn't wanted to release much slurry by jade stone so that the DMT card was needed to reach the milky slurry. Perhabs the DMT card has released some bigger chunks of slurry which has produced the deep scratches, I need ot investigate more on that.

Hope the post was of some interest for you.

happy honing

Philipp

It would be interesting to see what if any difference honing under running water would produce.

Nice work. Have you tried other slurry stones, I have been experimenting with a Translucent Ark slip.

Fascinating post and very very interesting.

I've read elsewhere that the larger garnets in the La Nouvelle Veine work better with a Unicot approach. It would be interesting to compare edges from this method.

Somewhere on this forum is a picture of a piece of chalk that explains why you have to take Visual Cues with a HUGE grain of salt

It shows the difference in stark contrast of the same surface and the same chalk and only a slight variation of Pressure applied to change the Striations

It is a great visual aid to really think about how much faith you put in micrographs that were produced at such a small minute scale using the infinite inaccuracies of the human hand..

How did the shaves feel :p


Sure wish I could find that pic for you

Quote:

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Originally Posted by gssixgun

Sure wish I could find that pic for you

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IIRC it was one of Euclid's posts. S'all I got :)

It’s an old Seraphim post.

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It is a GREAT illustration of what we THINK we see vs what could have caused it

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Originally Posted by gssixgun

It is a GREAT illustration of what we THINK we see vs what could have caused it

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Glen - I am sure you are right. The weird thing though is for the two Les Latneuses and the Nouvelle Veine, in my mind that's what I would expect the scratch pattern to look like. - Of course that could be wishful thinking on my part!!

I have a Latneuses with a cream side and a hybrid side. The creamy side cuts fast and leaves a fairly mid sharp but soft edge. The hybrid side is harder and slower and finishes with a much cleaner crisper feel.

My Nouvelle Veine is a puzzle - it is almost like honing on a mid grit stone - except it feels very smooth when I shave. The edge almost feels fluffy - smooth and fluffy!- except when I add the extra bevel with a unicot - then it cleans up well and is really good to use. (Apologies for the bad terminology... )


Of course - as you have said on multiple occasions - no two naturals are the same. I just find the pictures interesting because they kind of make sense to me based on my stones.

While I agree that a bevel micrograph is not a predictor of the quality of the edge or its ability to shave, Philipp has a nice collection of vintage Coticules and appears to be a capable honer, by the consistent stria pattern and very straight edges he has posted. It looks like he has been honing for a while.

And I would assume he is trying to produce the best finish from each stone, using the lightest pressure possible to finish, He is even using a non-friable rubbing stone, so the slurry is from the base stone alone.

So, while I do believe that bevel micrographs can be subjective, especially produced by any natural stone, Philipp has taken care to produce consistent results that are a good documentation of the finishes his stones can produce for comparison.

The quality of the micrographs is also impressive, having been taken with a cell phone.

Being naturals and especially being Coticules, one of the most difficult stone to master, based on my experience and that of thousands of others, (a Google search returned 65,000 hits), Phillip’s micrographs are an interesting demonstration of the potential edges these veins can produce.

Philipp’s finding is consistent with what most of us experimenting with naturals have found, harder stone are capable of producing finer stria, more polish and straighter edges.

For me, the Coticule edge is just not keen enough for my taste, and that is exactly what many like about the Coticule.

Philipp, how do the shaves compare?

Thank a lot,
happy to read all the positive feedback!

Actually I have not yet shaved of all of the coties listed above.

La Nouvelle Vein was my very first stone for razor honing 2 years ago. Looking back I can say it was a bad Idea to start the sharpening journey with a Coticule. I‘ve spent several weeks scrubbing a hell out of the razor and the stone, wondering why the slurry turns that black but the razor does not reach anywhere near to a shaving condition :S
Purchased several other coties and other hones, selled lots of them again, changed razors and so on... until I‘ve started to change the way I‘m honing :)

The La Nouvelle Vein was laying in a shelf for one year, got it out recently after I‘ve learned to finish on the La Veignette ballancing it on my fingertips.

My facial hair-skin combination seems to require very keen and very smooth edge, below HHT4 I don’t think of test shaving.

La Veignette (fingertips-finished) gives me a very close, effortless and mellow shave with a level of comfort which I would call „as good as my shaving technique“. Shaving was tested with the Filarmonica 14 double temple. Remark: until today I can only get high HHT results of La Veignette by putting another finisher between „working on slurry“ and „finishing“, with classic dilucot I couldn’t exceed the solid HHT3 level yet.

My recently purchased small La Dressante provides higher level of keenness with the same level of comfort, perhabs slightly below (but maybe it was a shaving technique, I‘ve shaved only 2 times of it). And it does not auto slurry! Have not shaved after full dilucot yet, have touched up my Fili 14 on it with water only. It’s definitely my new favorite :)

Les Latneuses I have also purchased in time I could not properly hone, after some tries and errors it has accompanied the La Nouvelle Vein in the shelf. Will involve it back into my team of „active stones“ :)

The grey one is very new and came together with La Dressante. No experience with it apart of this test.

Currently I‘m occupied by taking care of my damaged PC, but after I plan to spend more time on coties.

Will then also take some unicot pictures, and probably also under running water.

Looking forward to learn more about the „yellow mystery“ :)

Regards

Philipp

Quote:

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Originally Posted by Euclid440

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The quality of the micrographs is also impressive, having been taken with a cell phone.

...

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Thanks, perhaps my experience out of my previous hobby „photography“ is helpful here :)

Here is my photo-stream:
Rein -e- Art | Flickr

Regards

Quote:

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Originally Posted by Philipp78

Thank a lot,
happy to read all the positive feedback!

[...]

La Nouvelle Vein was my very first stone for razor honing 2 years ago. Looking back I can say it was a bad Idea to start the sharpening journey with a Coticule. I‘ve spent several weeks scrubbing a hell out of the razor and the stone, wondering why the slurry turns that black but the razor does not reach anywhere near to a shaving condition :S
Purchased several other coties and other hones, selled lots of them again, changed razors and so on... until I‘ve started to change the way I‘m honing :)

[...]

Les Latneuses I have also purchased in time I could not properly hone, after some tries and errors it has accompanied the La Nouvelle Vein in the shelf. Will involve it back into my team of „active stones“ :)

[...]

Looking forward to learn more about the „yellow mystery“ :)

Regards

Philipp

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That sounds about right: initial frustration, wondering why this damn rock won't do what I want it to; leading to slow realisation that maybe, just maybe, I have to suck up my pride and re-evaluate my expectations and approach. Incidentally, my first coticule was a La Veinette.

For learning how to use a particular stone, the recipe seems to be to just focus on one at a time and give it a bit of time. Also, for honing in general, stop before it becomes too frustrating. A challenge is nice, but there's no reason to let honing mess up your mood; this is supposed to be fun, you know.

I've heard La Nouvelle Veine is among the trickier veins to master, which means it might not be the ideal coticule to start learning on. Or maybe it's perfect, giving you a real challenge and making most others seem much easier after mastering it.

So obviously now I want one :p.

Anyway, good luck with your explorations.

Best regards,

Pieter

Quote:

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Originally Posted by Euclid440

For me, the Coticule edge is just not keen enough for my taste, and that is exactly what many like about the Coticule.

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If you find at some point a coticule that has a La Lune backing (I think some sold even with La Lune logo or something, but not all had the La Lune stone back), it might give a keen enough edge. They all seemed to be very hard and fine. Mine is the hardest and finest coticule I have ever found so far. And by far the sharpest coticule edge and a very sharp edge compared to anything, but not aggressive.

I have several natural Coticules and several of the “French” stone, probably some La Lune, though none of mine are labeled.

And yes, they can deliver a keener edge. There is a lot of history written on the French stones here and elsewhere and a lot of mystery about these stones. Seems those that knew the details are gone now.

Euclid440, have you tried to finish with another stone (e.g. the french one) providing the level of keenness your need and then go back to Coticule and do some ultralight strokes.

By this I can reach the HHT5 level on my La Veignette and La Dressante.

To me seems like some cotirs have a quite jump between the coarse „slurry-sharpenong“ and the „poloshing with just the tops of garnets sitting in the stone“.

No, really, I have moved more to Jnats, that provide a keener and smoother edge. I have not experimented with Coticules much, in the last couple years.

Though I buy them when I find them at good prices. I did pick up a couple nice ones recently at an antique flea market.

Perhaps I will dig them out and give them a go. I see Glen did the same.

Quote:

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Originally Posted by Euclid440

Perhaps I will dig them out and give them a go. I see Glen did the same.

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That is the true beauty of these threads, I had not touched my BBW since maybe 2010 maybe 2011 that thread made me finish a few razors on it this past week

:)

OK gens,

I had some time and have done some further experiments.
This time the unicot edges.

Before each coti I've kind of "reset" the bevel surface on my recently purchased nakayama kiita (super hard) without a tape.
Kiita is a very fast and very fine stone, so it can easily remove the previous unicot bevel and put a haze finish to the whole surface.
Then applied fresh piece of tape and performed between 50 and 100 strokes depending on the speed and size of the given coti.
For some of coties I've done the procedure under running water to reduce the impact if loose garnets.
Each time i was holding the stone on the fingertips (see: Getting higher HHT of Coticule) to apply a possibly low pressure and to get the finest possible edge.
HHT tests were done using one single long hair for all stones.

For comparison I'll put the dilucot pictures presented at the beginning of this thread.




La Veignette
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You see compared to dilucot much higher polishing was achieved at the very edge. The edge has passed HHT4 to HHT5
Seems like despite honed under running water still some single garnets have been released and hit the edge.




La Dressante
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Here the same story, very keen edge passing HHT5 (silent slicer).



Next Les Latneuses, hybrid side:
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Hybrid Les Lat has produced the finest edge so far also passing HHT5.




Next Les Latneuses, yellow side:
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Here seems like the larger/more aggressive garnets have impacted the very apex of the edge (see the white line along the edge).
Still HHT3 to HHT4 was possible with the same hait as tests above.




The unknown shallow grey:
Attachment 302857Attachment 302858
Seems like this hone either does have some single garnets of larger size or it does release some while honing, perhabs next time will try to hone under running water.
Unicot edge has passed HHT4.



La Nouvelle Veine:
Attachment 302855Attachment 302856
Thats definetly the trikiest one. The pressure seems to be the most critical to the results, I needed several attempts to achieve the results displayed above.
But once there a very keen and fine edge has appeared, HHT4+

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On La Nouvelle Veine I've also noticed that the condition of the surface (refreshed vs. already used for a while) can significantly influence the results.
If the surface of the stone was just refreshed (e.g. after lapping of at the end of the dilucot procedure) the unicot provides much coarser edge.
Here a comparison:
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After the left picture i've performed around 100 additional strokes which seemed to have conditioned the edge.
Then refreshed the bevel on Nakayama and finished unicot with 50 strokes.

Have also done this "sufrace condition" compare on les Latneuses, hybrid side:
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The right picture was taken before, i've just refreshed the coti surface and performed 50 strokes to see the "refresshed" effect.

And also with La Dressante:
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Hope those results are as interesting for you as they are to me :)

Best regards and happy honing!

Philipp

Wow, very interesting results and photos. The white line can be a reflection. I have notices this with very smooth shiny bevels and edges from a CBN edge, where the edge is very thin.

The test show what many have suspected, that edge damage can occur from slurry impact.

I too have suspected that the rough surface from a diamond plate stone can impact the stones ability to polish. I polish my stones with a Tomo Nagura or rubbing stone, after lapping. It seems to produce a smoother surface though, not burnished that reduces cutting ability greatly, just knocks down the rough diamond plate surface, which in turn produces a finer bevel finish.

You may want to try rubbing the stone smooth with a rubbing stone then rinsing off the slurry.

Are your photos pre-stropping? It would be interesting to see the impact of a strop, to see how deep the stria are.

Nice work, thanks for posting.

Thanks for the feedback :)

Actually the refreshing of the surface in my tests was done by small coticule slurry stone, diamond plate was not involved. The „burnishing“ effect seems to occur after about 100 finishing strokes on the stone. I think that then all the highspot-garnets are broken of/out and the tops of the remaining garnets are kind of burnished to a certain extend.

As per stropping:
Before taking pictures i‘ve run 10 strokes on linen to clean up the apex.
The effect of leather stropping is barrely visible at this magnification (x160)

Quote:

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Originally Posted by Euclid440

I too have suspected that the rough surface from a diamond plate stone can impact the stones ability to polish.

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In Grinding and Honing part 4 Bos warns against lapping with diamond because he says the sharper / harder diamonds shred the garnets in the coticule making them less effective for polishing. That would support what you say. Since reading that I have stuck to Silicon Carbide for lapping. I have also started pairing similar sized / types of coticules and rubbing them together after honing until the suction ceases. So far this seems to be quite effective for keeping them flat.

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Originally Posted by Seveneighth

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I have also started pairing similar sized / types of coticules and rubbing them together after honing until the suction ceases. So far this seems to be quite effective for keeping them flat.

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Good Idea! I think it works best if you have 3 stones rubbing their surface to to each other.
Having only 2 stones in your "lapping team" you might run into a problem that one stone develops a kind of "hill" in its surface and other the "tale" matching to the hill of the first one.

Philipp

Quote:

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Originally Posted by Philipp78

Good Idea! I think it works best if you have 3 stones rubbing their surface to to each other.
Having only 2 stones in your "lapping team" you might run into a problem that one stone develops a kind of "hill" in its surface and other the "tale" matching to the hill of the first one.

Philipp

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That's a really good point. I hadn't thought of that. I have enough stones of similar sizes to do that. - Thanks!!

Great photos by the way! - I am still trying to digest them. So many questions...

I like the way that the initial bevel from the nakayama kiita contrasts with the second coticule bevel. The coticule scratch pattern shows up nicely. I would be curious to understand the interplay between the scratches from the first bevel and the second when the unicot is performed on a single coticule. I still can't get my head around why, with certain stones, the unicot edge I get is so much sharper than a dilucot with the same stone.

Bart covers it in his original post:
https://sharprazorpalace.com/advance...le-honing.html

But it would be nice to be able to visualise what is happening to the metal. My guess is that the scratch pattern on the second bevel would intersect with the scratch on the original and even out the edge. Much like two hatching patterns on the shading of a drawing coming together to form a hard edge.

Just to chime in old coticules were never sold with a slurry stone. I haven't seen any ever sold in a box with a smaller stone or instructions asking us to use slurry on a Belgian hone.

Has anyone else?
I have seen instructions to use water or oil or lather. And I don't buy the idea that lather meant slurry, there's no evidence of that.

Quote:

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Originally Posted by Seveneighth

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I still can't get my head around why, with certain stones, the unicot edge I get is so much sharper than a dilucot with the same stone.
...

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I think that the slurry-dulling is playing a significant role here.
Coming from slurry stage in dilucot the edge needs to overcome the damage produced by the slurry at the very apex. Meaning during the dilution stage still certain metal needs to be removed.
But also in the dilution stage the slurry applies some dulling action on the edge.
So it could be tricky to refine the edge as long a any amount of slurry is present.

Now on water only Coticule might be too slow to remove the damage of the slurry at the very apex in a reasonable time.

Putting a tape to the spine significantly decreases the surface of contact to the stone. This boosts the refinement power of the same stone. Working that way allows to achieve the desired refinement with acceptable effort.

I am sure careful dilution and more work on water in dilucot can results in the same keenness of the edge as with unicot method. Haven’t achieved it my self yet...

"I too have suspected that the rough surface from a diamond plate stone can impact the stones ability to polish."

"In Grinding and Honing part 4 Bos warns against lapping with diamond because he says the sharper / harder diamonds shred the garnets in the coticule making them less effective for polishing. That would support what you say. Since reading that I have stuck to Silicon Carbide for lapping."

Two different things and not something we see, diamonds imbedded in a stone. A single 300 grit would be painfully obvious in a 6-8k grit stone.

Diamond plate are easier and faster, if you refresh often and you should.

For polishing, where you are only doing a limited amount of laps the smoother stone surface will polish better. For general honing the rough surface will wear smooth after multiple laps.

Quote:

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Originally Posted by Disburden

Just to chime in old coticules were never sold with a slurry stone. I haven't seen any ever sold in a box with a smaller stone or instructions asking us to use slurry on a Belgian hone.

Has anyone else?
I have seen instructions to use water or oil or lather. And I don't buy the idea that lather meant slurry, there's no evidence of that.

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Me neither, I've gone away from using them with slurry anyway

Philipp

Excellent thread and most excellent photos. How about a photo of your microscope?
Early on you said that you used a Jnat to refresh the bevel before using the Coticule, and that you did not use a diamond plate to make a slurry. I do not wish to misrepresent you so please correct me if I am wrong.

I have found that most any Jnat will contribute some slurry during a honing session, some more than others, and I have found that any slurry from a jnat or a coticule or on an arkansas will by adding that cushion of free roaming grit, will be prone to convexing the bevels of a razor. These less than flat bevels stipulate that when you next lay the razor on a flat surface the edge will be proud above the flat surface, in our case the next slurry-less stone. For this reason I suggest that you use a synthetic stone, one that does not self slurry to create your model bevels for you studies. A good hard synthetic, where the grit remains bound up in the stones matrix will give you flatter, truer and dependable model bevel for which to build your Coticule edge upon. This is evident from your "taped spine" photos where the edge seems to be more greatly affected right at the Edge. Any slurry can by its very nature change the geometry of a bevel, for you photos studies it is helpful to begin with a "V" shaped geometry rather than a "U" shaped or rounded bevels geometry. Having the V shape will give you more proof positive reading and photos.

About using a diamond plate on a Coticule, I agree that the diamonds can rip the garnets or shred them as suggested. Garnets are not friable if they are born in a soft binder matrix. If the garnets were of a mass of solid garnet all bound together a diamond plate would cleave them, but when they are bound in softer clay like matrix, they just come loose as whole/sized granets and abrade your razor with their rolling around as full size grit particles. The relatively softer matrix of a Coticule will disgorge the garnets before they would have a chance to cleave from a diamond. The Atoma or DMT will really only work or work especially well with Jnats because these naturals have a homogeneous stone matrix and friable silica grit particles. The silica and clay might break off in larger clumps from a diamond plate, but the water soluble clay matrix quickly releases these bundles packing and the silica is free to cleave as individual particles.

Back to the tape. I suggest that for your photos that you begin each session with a perfectly flat bevel made with an efficient synthetic that does not slurry and the go directly with out alteration to your Coticule, without an intermediate stone or abrasive before the Coticule. I like to, when doing this, create diagonal scratches with the synthetic and then with the Coticule as an example use only straight edge leading strokes. This gives good contrast and accounting as to the amount of steel that is being abraded by the Coticule at the edge. This is the approach I tried in this video. Again, your photos are great and I am sure authentic.

Alex

https://www.youtube.com/watch?v=ZnNrehJ7efI

Great pictures Philipp! You have a nice set up to get clear pictures.

Research science teaches you to take away as many variables you can so your peers can replicate the findings you are reporting on. Alex idea of jumping off a known synthetic is much more repeatable because you can go out and by that synthetic and colabrate or point out any variables you missed. A Nakayama is great but you can't go out and buy a Nakayama that has the same properties as yours(hardness, grit level,etc.) So a synthetic would be great in this application.

Playing in the mud is very effective and rewarding when you figure it out. Alex videos and personal help, helped to speed up my learnong curve and taught me to understand the influences that can happen and the effect they have on the edges.

Quote:

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Originally Posted by alx

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How about a photo of your microscope?...

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Hi Alex,

My magnification equipment is all except scientific :)

I am using a children’s experimental microscope at 160x magnification (10x objective and 16x eye-piece).

I am taking pictures with my cell phone hand held through the eye piece. This setup produces some optical issues like spherical aberrations (getting blurr towards the sides of the picture) and chromatic aberrations (yellow-blue lines along the contrast edged) wich are not easy to come around. But in their center the pictures are quite useable.

For illumination I am using an LED desk light turning its head in a way to get side light. Before taking a picture I turn the razor to get maximum light reflection from the scratches.

I put the razor on a magnetic self made wedge-holder.

Here are some pics.
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Quote:

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Originally Posted by alx

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Early on you said that you used a Jnat to refresh the bevel before using the Coticule, and that you did not use a diamond plate to make a slurry. I do not wish to misrepresent you so please correct me if I am wrong.
...

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Alex,

Yes, I am was using my exceptionally fast and fine nakayama kiita I got from a friend of mine (on its back there is a number #726 ;-)).

I haven’t gained much experience on that stone yet but as of now it can produce for me HHT4 edges finished on milky tomo slurry.

Refreshing was done without tape. Nakayama can easily remove the unicot-second-bevel produced with taped spine before.

Yes I am aware of the micro-beveling effect of the slurry. I was hoping that when finishing with tape the higher angle (caused by applying tape) can compensate any microbevel from the nakayama-tomo-slurry. This for me was kind of proven by the fact of getting higher HHT results of the unicot finishing on Coticule.

As per synthetic finisher for refreshing: you’re absolutely right, this would definitely help in terms of consistency, repeatability of the tests as well as it would allow others to reproduce them.
But I have never used high grid synthetic and currently not planning to do so. I am a fan of natural hones, to me putting of a blade to a piece of natural rock has something magical to it. I love how they feel to my hands, love the earthy smell and the uniqueness of the each and any stone.

As they say 'Many roads lead to Rome' you found a nice one! Good job!
I can totaly relate to the natural stone fascination, they are sweet once you figure them out.