Encyclopedia of razor edge images.

[JohnDee]

Very interested to read this as I am very new to all this and have been struggling hence my posts on the Honing forum. I have just acquired this little double-sided Coticule. Early signs are promising and I too noticed that it does not give a "pretty" edge.
C.

I've a coti like that with gray swirls like yours. It's very hard and it can give a very keen edge.

I assume that bottom of your coti is usable BBW (lapped). If so, you can use it like this:
- Coti side with coti slurry
- BBW with coti slurry
- BBW with water
- Coti with water

In the slurry phase I rinse half of the hone after 20-30 laps to dilute the slurry.

I can't give you the exact number of laps I use with this method, because I hone based on feeling. With this method I always get very keen but smooth coti edges.

 

[Cambouis]

I've a coti like that with gray swirls like yours. It's very hard and it can give a very keen edge.

I assume that bottom of your coti is usable BBW (lapped). If so, you can use it like this:
- Coti side with coti slurry
- BBW with coti slurry
- BBW with water
- Coti with water

In the slurry phase I rinse half of the hone after 20-30 laps to dilute the slurry.

I can't give you the exact number of laps I use with this method, because I hone based on feeling. With this method I always get very keen but smooth coti edges.

Thanks.

Yes the dark side certainly seems to be very hard indeed and is absolutely flat, checked with my steel ruler.. The yellow side is soft and since it is not that thick, I shan't use slurry. I lapped the yellow side yesterday and slurried it and was surprised that it had worn so much. I shall be careful henceforth.

Best wishes

C.

 

[CBLindsay]

I've a coti like that with gray swirls like yours. It's very hard and it can give a very keen edge.

I assume that bottom of your coti is usable BBW (lapped). If so, you can use it like this:
- Coti side with coti slurry
- BBW with coti slurry
- BBW with water
- Coti with water

In the slurry phase I rinse half of the hone after 20-30 laps to dilute the slurry.

I can't give you the exact number of laps I use with this method, because I hone based on feeling. With this method I always get very keen but smooth coti edges.

I recently began testing this exact process with pretty pleasing results. I can't claim to have come up with the idea entirely on my own, I believe I read something from Bart that indicated the BBW (although slow) has the ability to jazz up the edge a bit. From the few razors I have done this with, I think I am certainly getting better shaves. Whether it is from the BBW adding to the quality or just the time spent on the stone ...don't know. I have also played with using a BBW slurry on the coti side instead of the BBW itself, I am not experienced or wise enough to draw a conclusion on this one.

More on topic (to the original thread).
I am noticing the Diamonds plate provides significantly more uniform (straight) scratches, as does that 13k that was pictured. I thought I was going crazy or doing something wrong because my own edges go from the straight scratch pattern on the king stone(s) I often use to set the bevel to squirrely like the ones pictured once I move tot he natural Coti's etc. Makes sense but I still wondered if it was just me or my stones.

good stuff here!

 

[McVeyMac]

Chris, I have recently honed an edge where I did the bevel set through finishing completely on Arkansas stones. I was not looking at the edges with the magnification shown here, but I will tell you that the edge was not straight as an arrow as are the synthetic examples shown above. But it shaved beautifully with a great deal of comfort.

 

[SliceOfLife]

My theory about this is that the coticule with the toothy edge perforates the hair and after that it is easy to cut the whole hair. A synthetic edge without the teeth is just pushing against the hair and with force it goes through. This is in my opinion the difference between a smooth and not so smooth edge.

You can compare it with a box that is closed with tape (hair). If you try to open it with your finger (synthetic edge) pushing through the tape, you will have a hard time. But if you punch a hole in the tape with the tip of a key (toothy coti/natural edge) it will be a piece of cake to open the rest with just your finger.

The thing is that the Coticule edge isn't really toothy. Keep in mind that's over 2000x magnification. That "tooth" would be hard to see even at 400-600x. The DMT edge is just insanely straight. Some coticules do create a somewhat toothy edge... but not all... and many create edges even straighter than this one. I've posted a picture or two of coticule edges that rivaled the highest grit synthetics for lack of "tooth"... and those are some of my best coticules.

Some people think coticules comfort comes from being "just sharp enough" to cut hair but resist cutting skin. I Disagree with this for several reasons. First, skin is easier to cut than hair. A lot easier in fact. You can exert many many many many times the pressure against the razor edge from skin vs hair. So it doesn't make sense. Second, I've got plenty of coticules that can make edges that shave significantly closer (are sharper) than PLENTY of extremely sharp edges that just love to cut skin.

Your theory doesn't agree with my experience either, because as I've said, tooth varies from stone to stone and that variance doesn't seem in any way related to comfort in my experience.


What I suspect is that the geometry of the edge and the bevel right behind the edge tends to keep the edge level on the face, and depress variances in the skin surface moreso than penetrating them; so less "catching" on skin cells and disrupting them. Every razor is removing skin cells while you shave. I believe the topography of a coticule edge is such that it tends to remove less. That's it.

But my point wasn't to specifically compare Coticules against synthetics. Thuri's don't look as good in profile as many synth edges, and very few Jnats do either... and the ones that do aren't necessarily the best shavers. The coticule was just the stone I happened to grab, since they're so well regarded for the quality of the shaves they give.

 

[SliceOfLife]

I recently began testing this exact process with pretty pleasing results. I can't claim to have come up with the idea entirely on my own, I believe I read something from Bart that indicated the BBW (although slow) has the ability to jazz up the edge a bit. From the few razors I have done this with, I think I am certainly getting better shaves. Whether it is from the BBW adding to the quality or just the time spent on the stone ...don't know. I have also played with using a BBW slurry on the coti side instead of the BBW itself, I am not experienced or wise enough to draw a conclusion on this one.

More on topic (to the original thread).
I am noticing the Diamonds plate provides significantly more uniform (straight) scratches, as does that 13k that was pictured. I thought I was going crazy or doing something wrong because my own edges go from the straight scratch pattern on the king stone(s) I often use to set the bevel to squirrely like the ones pictured once I move tot he natural Coti's etc. Makes sense but I still wondered if it was just me or my stones.

good stuff here!

Uniformity is a big part of what makes higher priced synthetics cost more than cheaper ones... and few naturals match synthetics for particle size consistency... but also keep in mind that my synthetics are often wider (Both were 3" wide), which means I do a lot more straight honing... and without an X-stroke, the pattern of my strokes will be more consistent because a straight path with the heel riding the edge of the stone is easier to do consistently than an X stroke. This will prevent as many furrows crossing one another at anything but the most insignificant angles (fractions of a degree)... whereas an X stroke will likely see a greater degree of this. So that contributes to the patterns looking more uniform as well. This also helps to notice when you get foreign grit or just encounter an unusually out of spec abrasive particle on your stone... and therefore lets you correct any damage this might have done immediately.

 

[SliceOfLife]

Since the thread's sort of taken a tangent. Let's see if we can reach a consensus on something.

This is not the razor used in the rest of this thread. It's a nearly 21* razor. Steel a little softer than average.

First two pictures are both sides of the razor off the 8k. The black stripe is just water I didn't wipe off fully before taking the shot.
Third picture is off a new (to me) vintage barbers hone. Your usual instructions: "Don't do more than 5-6 strokes or it'll overhone and you'll die of bad shave!" I did somewhere between 70 and a 100 strokes, until I was confident the evidence of the 8k was erased.

Does this look like a good edge? Is it "overhoned"? Is it going to be sharp enough to overcome the razors extremely high grind angle? Will it be a comfortable shave? Will the edge hold up? (This one is kind of a freebie) How will the edge appearance under magnification differ when I use the same technique and hone on the usual (much lower grind angle) razor?

Feel free to make your assumptions and justify them however you like. I'll post results in a day or two, as well as images of this thread's usual razor off this hone... and the hone itself

 

[JohnDee]

Maybe our theories are both far fetched. Maybe the reason why a Coti gives a smooth edge is right in front of us. Could it be that the smoothness is a product of the not-overhone property of the Coti. For me a coti always gives a consistent smooth edge even with the sharpest edges. A synthetic is a hit and miss in the smoothness department, but I can get a smooth edge from a synthetic.

Because the coti cannot overhone (maybe there is an exception for some) an edge, therefore the resulting edge will be a sturdy edge. A synthetic can easily overhone and the result is a flimsy edge. This flimsy edge will dig into your skin when you shave, but the sturdy coti edge will not. I don't think it's the sharpness of an edge that makes an edge harsh, but the flimsiness.

A coti gets close to an optimal edge, but doesn't go beyond an optimal edge. Even a harsh shaving edge doesn't have to be overhoned. Just shave with an edge with a sub-optimal bevel. It can shave, but it will be a harsh shave.

 

[JohnDee]

I think the edge from the barber hone will give you a good shave, but it's possible that it will feel a bit harsh on your face. I've shaven with edges like that and they gave me a good shave. But as always a picture cannot tell if a shave will be good or not. You just have to try it. I look forward to the actual results.

 

[SliceOfLife]

So John, it sounds like to you, "overhoning" simply means refining a razor past the point where the edge will survive the shave without losing so much keen that it injures you. I've always thought people were using it more to refer to some mystical or actual damage to the edge that causes it to fail immediately upon any use... like a wire edge, possibly synonymous with wire edge, or foil edge, or false edge... but maybe something else entirely. It was this catch all boogieman phrase to explain a bad honing and rather than find the actual failing in technique, simply say that you "overhoned". Maybe the hone was garbage and the idea was to only do 5-6 passes, because then you might thin the edge enough to sharpen but not enough to tear the edge up with the junky assortment and arrangement of abrasive in the hone. Maybe the user had no clue what he was doing and was mashing the spine of the razor into the hone or rattling around the edge trying to hover the razor over the surface of the hone, and the fewer passes done, the better. Whatever the problem... it's "overhoning"

What it sounds like you describe... refining an edge thinner than its grind angle and steel type allows while still maintaining a both decent and recoverable through stropping edge throughout a shave... is something that actually exists; but it's the first time I've seen someone suggest that's what they consider "overhoning". It's not usually used to qualify the results of a hone functioning too well on a tool whose specifics and purpose it is unsuited for, but rather to wipe away the blame of a hone or honer functioning too poorly.

On that point we may find some common ground... although it's fairly complicated... as there are certainly razors I have that I can't use particularly high grit hones on, because the edge is so thin and brittle it fails... while these same hones function fine with other razors and these same razors function fine off other hones. And yes, certainly plenty of bad shaves can be had by taking a thin edge too far on the hones... but these same hones can work on thicker edges or edges with different steel... so it seems like there's more at play with regards to coticules vs other hones than simply that the other hones edges degrade more... though I'd agree that coticules seem to typically create rather sturdy edges for shaving.

 

[kcb5150]

The coticule abrasive isn't particularly sharp. They're like slightly boxy beads. French finishers and vermont slates seem to be quartz bombs and aggressive cutters. The edges off of them can be ridiculously keen but hot and brittle on certain blades for me, usually ones I had to knock oxidation from.

 

[kcb5150]

It's probably why ark edges are so comfortable also. They don't cut in a typical way in a finisher capacity.

 

[SliceOfLife]

That smacks of moving into the old steel removal vs burnishing theory. I think it's dangerous ground if we're not prepared to take it to the extreme and argue that an ultra-polished sheet of glass or other very hard material becomes the ultimate finisher. I know there's one member here who loves his finishes off nearly-nonabrasive "gem" rocks... but I don't think I've ever found a second. And my results with them have been pretty, but very sub-par shavers, especially for the appearance of the edges.

Also, based on what I've seen under the scope, coticule garnets are plenty sharp. If anything they're far more jagged than the reputedly quartz particles I find off many slates which approximate spheres much better. Also, if the garnets cutting method is the key, wouldn't Les Lat hybrid lose this edge character, since much of the cutting from it is supposedly done by sub-micron quartz?

 

[SliceOfLife]

Was it a good edge? Yes and No. The hone seems promising... but also not. The razor shaved like a sharp razor WTG (but we all know how dull a razor can be and still shave well WTG). On the second and third passes, there was definitely a problem. It shaved, and it shaved close-ish... On par with some of the mid-range barber synths from my testing (which used a closer to average angled razor), but you could feel the razor moving the hairs before the cut initiated... that's a bad sign when shaving. Also, there was a velvet feel if I ran my fingers ATG on my skin just an hour after the shave... so certainly less close than I consider acceptable for me.

Is it overhoned? That was kind of a tongue in cheek question, which I hope my post about "overhoning" above explains why.

Is it sharp enough? Ahh here's the thing. For a barber hone? Certainly. This was a pretty good shave measured against other barber hones. If this hone was marketed to sharpen this exact razor... I'd say it was a fair level of success it achieved at its task considering the competition it was marketed against. For me? No. But again to be fair... I've yet to find a razor over eighteen degrees that gets sharp enough for me. So far (with limited testing) it seems that the loss of cutting power hits a breakpoint right around eighteen degrees (by how I measure) that no amount of polish can overcome. Just like you can't grind a razor to five degrees and then shave well off a King 1k, there's seemingly breakpoints in one element of sharpness that no increase in the other elements can overcome. And this razor falls outside of it. BUT... like I said, I haven't toyed around with it too much. And as this may be the "dullest" (by edge angle) hollow ground I've ever owned. It will be a curious toy to experiment with. The shave wasn't abysmal... and perhaps off one of my extremely fine jnats, or a synthetic, or some incredibly over-refined paste (Don't they have 40ths of a micron now?) it could teach me something. So it'll get a few more shaves for science.

Will it hold up? Ahh, here's the "but" for the hone. At this angle, I'd expect most edges to show almost no change after a shave... just like I'd expect an axe to not change much if I used it to gently slice a tomato in half. And while the edge didn't look terribly beat up post-shave... it showed a level of wear I'd consider typical for much thinner ground blades. I expected the edge to be laughing and asking for more... instead it was saying "strop me plz". Possibly the hone is the reason... possibly the steel... a bit more testing will show.

Thin Blade edge under scope off this hone: Picture below. Here I went to the other extreme. From a somewhat soft steel hugely thick grind angle... to a somewhat hard steel extremely thin grind angle. And I gotta say... this is enough to get me excited about this hone. I'll try and review it in the next week or two. I'll be surprised if this edge manages to hold up for the shave... but if it does, I expect it to be a great shave.

BUT that will wait... because I'm more excited to play around with the fatty blade on some of my more extreme levels of refinement... and see just how the blade performance and wear and tear change. Tonight I'm going to take it to my SP 13k... and maybe one of my more picky Jnats (Edges off most razors under 15* just dissolve in use off it) tomorrow.

 

[wetshaveyyc]

I think every image in this thread looks the same. The one thing that stands out, however, are the very deep grooves left by the harsh 8k DMT, further demonstrating my previous suspicions. Thanks!

 

[SliceOfLife]

Feel free to point one of these grooves out.

 

[JohnDee]

I think we mean the same thing when we talk about an overhoned edge. A wire edge or burr. My point is that you can possibly overhone in several gradations. An overhoned edge doesn't have to be a wire edge that's flapping around like a inch of tin foil. I mean a subtle overhoned edge. A wire edge to small to see or feel with you finger, but it's there to dig into your skin, because it's still fragile/flimsy.

 

[SliceOfLife]

Ahh, not quite. Wire edges do definitely vary. But I was thinking more specifically of an edge that hadn't wired (it had no distinct line of fatigue)... but simply lacked the durability to survive its intended purpose. So for instance, a filet knife would typically be "overhoned" for use as a hatchet... not because of the honing, but functionally the state of it would be the same. I would think that a real wire edge wouldn't qualify as "overhoned"... because, well, how do you correct a wire edge? And from my perspective an edge never wires due to too much honing. It typically wires because of the state of the hone and/or the user's technique. For instance, DMT's are reeeeeeallly easy to pull a wire on, but it's not related to the amount of honing. I can probably do it in a single pass if I wanted to. It has a lot more to do with pressure (or just never clean your DMT, then it'll wire with time after a few dozen tools worth of swarf getting packed down into it).

 

[SliceOfLife]

With the right razor, didn't even take a full pass. Just have to try and hone the exact opposite of how the directions say.

 

[JohnDee]

With the right razor, didn't even take a full pass. Just have to try and hone the exact opposite of how the directions say.

Yes, I know what you mean and what you did. I also know what I mean, but I cannot put it into words.
Maybe the idea of the term overhoning that I have is not what is generally used for overhoning.

I assume you did spine leading strokes on the hone to create this edge? Is this what you mean by overhoning?

Maybe over-refined is the word I should use what would result in a fragile edge and less than smooth shave.