Thread: Clarification of my opinion on the honing techniques of the Koordenwinkel

After my disagreement with Bart about the koordenwinkel, I feel I should clarify in more detail why I have that opinion about their honing technique, and the importance of the flaws in some of the coticules they sell.

Please note that both approaches to honing work. They are just very different.
I thought long about whether I should post this or not, but I decided to post because I don't want people to get wrong ideas about the koordenwinkel after reading my earlier comments. It's a nice shop with lots of good stuff, and the people there are friendly and helpful.
They are in part responsible for the revival of straight razor shaving in Belgium, and I commend them for that.

My issue with the koordenwinkel is that I disagree with them on the subject of honing and hones.

Standard SRP way
At SRP the default honing technique (lapped stones, 12K finishing stone or better) results in a triangular edge (with optionally a teeny mircrobevel)
The resulting edge is very sharp, and it stays vary sharp for a long time.
This is imo because repeated stropping turns the edge from triangular into teardrop shaped.
The only way this happens by stropping on leather is because the tip of the triangular shape makes good contact with the strop and is 'abraded' easily. This mechanism is similar to the way that if you tape the spine, the first couple of passes take away metal at a great speed, because the point of contact is so small.

As the bevels get wider (or as the teardrop is shaped) the contact surfaces get bigger and the abrasion slows down.
This means that the edge is 'sharpened' by the stropping, and any microscopic edge damage gets removed by the strop. (Microscopic is the keyword here).

Their way
At the koordenwinkel, the first difference is they don't lap their stones. The reason is that it doesn't matter in their honing routine.
They start out on the coticule with slurry, and then make X movements like we do. This continues until the razor passes the TNT (their variation of it. same difference).
Then they switch to a pasted loom strop with dovo red paste. An important sidenote here is that the strop is not fully tensioned. It is slightly loose, causing it to droop a bit when the razor passes.
The red paste is equivalent to the norton 8K in grit size, though less aggressive. It would probably compare to a 12K norton.
Then they strop and shave. At that point the razor is shaving sharp. Note that at this point, the edge is teardrop shaped already because of the non-lapped coticule and the slightly drooping pasted strop

Why I think our way is better
Following their way, it is relatively easy to hone a razor, but this ease comes at the price of having to refresh the edge frequently.
Stropping on leather only will not remove the microdamage, because the lack of triangular edge means that it won't be abraded by the leather.

The SRP way of honing takes longer to learn. The reason is that there are so many mistakes you can make, and so many ways to mess up the triangle. However, once you have it, the end result is that your razor stays sharper for a long time.

I have used both honing methods (since I started out using theirs) for some time.
Theirs is easier to learn, but you need to touch up frequently on the pasted strop
And the razor won't be as sharp as stone finished edges (assuming a 12K finishing stone or better), unless you also use finer pastes than the dovo red paste. If you use .5 chromium oxide or diamond paste, then the sharpness should become equal, or at least they should be within the same variations.
Our way is hard to learn, but edges can be sharper, and last longer.

It's a tradeoff, but for people who are in this for the long term, I believe our way is preferable, once you have the hang of it. The simplest reason is less time between touchups.

Why I don't like their honing course and technique
There are 2 problems I have with honing as it is taught at the koordenwinkel. Again, this is just my opinion, and not a judgment about sharpness or shavereadiness.

The first is that the skills and materials are not easily transferable.
Some of the coticules they sell are unsuitable as finishers as we use them.
In their way of honing, that doesn't matter because they only use the stone to get the edge to the TNT sharpness level. They finish on paste, not on the coticule. They use the coticule where we would use a 4K stone.

So a coticule bought there will be good for what they use it for, but it might be unsuitable for finishing after the norton 8K or similar stone.
The techniques are also not easily transferable, because they omit a lot that we depend on, like lapping, and chamfering of the edges of the stone. Leaving the loom strop loose is also a certain way to destroy your triangular edge. There are more issues but listing them is not what this thread is about.
People wanting to learn honing as we do will have to overcome several hurdles, and unlearn a lot in order to make the switch.

The second issue is maybe not entirely objective, but they also have different standards about when a razor is beyond hope of honing (let alone restoring), and they make no mention of other stones than coticules.
My razor had a double bevel due to extremely bad stropping on the pasted strop (my newbie sin ) and the advice I got was to ship it to dovo for regrinding, or spend 12 hours on the coticule to get it back.
When I hone such a razor now after restoration, it only takes half an hour on the 1K to reset the entire bevel.

As long as a razor is in good condition, they can get it sharp as I mentioned before
But as soon as a razor is in less than ideal shape, the people at the koordenwinkel are lost because their way of honing is not suitable for doing any real metal removal.
Perhaps this is not wholly fair on my part. I realize that repairing or restoring a razor is not for everybody, but at that point I feel they should simply mention that the razor is not lost, but can be restored or repaired if you have the correct equipment or know someone who does.
Then the people would know that a razor with minor damage is not lost. Especially with an expensive TI, that would be a big waste.

I have to admit that I don't know of all the people who use straights, how many care as much as we do (few, I guess) and how many would care for restoration (very few probably).
I all likelyhood, restorers like some of us are to the average shaver as the mechanics who restore a1960 MG are to the average car owner.

The end
I hope that with this, I have sufficiently explained the reasoning behind my opinion on the koordenwinkel way of honing. To summarize:
1) They can hone a razor so that it is shaveready, just as we do.
2) Their way is probably easier to learn.
3) But the fact that they start with the teardrop shape means it needs to be refreshed more.
4) They have a low threshold to judge a razor un-honable or lost.
5) Knowing their way of honing can make it harder to learn our way of honing.
6) The koordenwinkel is a very nice shop for lots of edged stuff, like razors, scissors, nailclippers, chef knives and lots more

Bruno,
That is a great and thorough write-up about the Koordenwinkel's approach and methods.
I fully second everything you wrote with exception of a few minor things.

-The Dovo green paste is coarser than the Dovo red paste. (I don't know what's in it, but it surely is way coarser than O.5 micron Chromium Oxide from HandAmerican. Dovo also has a black paste that is finer than the red paste. (red is about 3 micron, black about 1 micron)

- A convex edge is perfectly stroppable, but it might ask for a bit more flex in the strop.

I concur with everything else.
Maybe as a final addition, because they are reviewed here after all, a link to the website:
De Koordenwinkel / shaving-and-razor-shop.com

Kind regards,
Bart. (no affiliation with that store whatsoever)

Originally Posted by Bruno

1) They can hone a razor so that it is shaveready, just as we do.

I've been using a similar technique for a year or so and agree that it makes a perfectly shave-ready razor.

Originally Posted by Bruno

2) Their way is probably easier to learn.

An awful lot of beginners over here lean on the pasted strops pretty heavily in the early months, which would seem to confirm that the SRP way is harder to learn. This is a positive feature of their technique, IMO.

Originally Posted by Bruno

3) But the fact that they start with the teardrop shape means it needs to be refreshed more.

I don't think this is necessarily true. Lots of guys here do a double or triple bevel, which gets you the same effect, and it doesn't seem to be the case that they also need to refresh more often. From personal experience if there's any difference it's minor.

Also, if you're worried about this then keep in mind that you can give the razor a few laps on a medium grit hone and flatten out the arching in the bevel. This isn't a touch-up since the hone doesn't touch the edge, but by flattening out the bevel it makes it easier for the strop to keep the edge going and going. I suspect this is probably what the barber hones really did. I see a lot of dished barber hones, and this technique explains why these hones still worked in such poor shape.

Originally Posted by Bruno

4) They have a low threshold to judge a razor un-honable or lost.

I consider this a feature of their technique given what's coming out of Dovo and TI lately. A major feature.

Originally Posted by Bruno

5) Knowing their way of honing can make it harder to learn our way of honing.

This is only a problem if their way of honing is inferior to the SRP way. I'm not sure that's the case. It's easier to learn and works well without change on a wider variety of razors, and doesn't seem to (edit: I just noticed that this sentence just ends here and I can't remember what I was trying to say...)


Another major feature of this technique is that it doesn't need expensive high-grit hones. Just something to get the bevel more-or-less ok in a reasonable amount of time, then sharpen it on the strop. Personally I like to keep my hones flat anyway, but the fact that their technique works on hones in such poor shape is a good sign.

Originally Posted by Bart

-The Dovo green paste is coarser than the Dovo red paste. (I don't know what's in it, but it surely is way coarser than O.5 micron Chromium Oxide from HandAmerican. Dovo also has a black paste that is finer than the red paste. (red is about 3 micron, black about 1 micron)

Thanks. I changed it

Originally Posted by Bart

- A convex edge is perfectly stroppable, but it might ask for a bit more flex in the strop.

For the purpose of stropping it won't matter, though you need a bit of extra flex.
But unlike with a triangular edge, you won't remove any metal by stropping because the edge already is teardrop shaped. Triangular edges become teardrop shaped, so over all the time that you strop that edge, you get 'free' sharpening

Originally Posted by mparker762

Lots of guys here do a double or triple bevel, which gets you the same effect, and it doesn't seem to be the case that they also need to refresh more often. From personal experience if there's any difference it's minor.

I've thought about the double or triple bevel, but the same principle applies there: the stopping will abrade the multiple bevels into 1 teardrop over time.
Also, I should have mentioned, but the amount of droop they use with the pasted strop is significantly more than the difference in honing angle if you use tape for a double or triple bevel.

Originally Posted by mparker762

Also, if you're worried about this then keep in mind that you can give the razor a few laps on a medium grit hone and flatten out the arching in the bevel. This isn't a touch-up since the hone doesn't touch the edge,

Maybe it is not a touchup if you define it like that, but it does require me to bring out a hone, which amounts to the same difference. Imo, the time between using anything other than a leather strop should be as long as possible

Originally Posted by mparker762

but by flattening out the bevel it makes it easier for the strop to keep the edge going and going. I suspect this is probably what the barber hones really did. I see a lot of dished barber hones, and this technique explains why these hones still worked in such poor shape.

That is correct. Dished stones are not a problem as long as you use this technique. Which is good from a convenience point of view, but you have to touch up more frequently

Originally Posted by mparker762

Originally Posted by Bruno

) They have a low threshold to judge a razor un-honable or lost.

I consider this a feature of their technique given what's coming out of Dovo and TI lately. A major feature.

I meant something else.
(and I didn't want to bring this up again ) they consider anything that comes from TI or Dovo to be shaveready. They made that pretty clear.
What I meant was that if a razor has a nick that is only half the size of the bevel width, they consider that razor ready for the junkyard unless you want to send it back to TI or Dovo for regrinding.

Originally Posted by mparker762

Another major feature of this technique is that it doesn't need expensive high-grit hones. Just something to get the bevel more-or-less ok in a reasonable amount of time, then sharpen it on the strop. Personally I like to keep my hones flat anyway, but the fact that their technique works on hones in such poor shape is a good sign.

Our way also doesn't need expensive high grit hones.
I admit I have over 4 digits worth of hones, but that is luxury, not necessity.
I don't use pastes anymore, and my Howard bought coticule is a perfect stone for honing AND finishing.
If I swap my coticule I bought there, for the coticule I bought from Howard, I have a perfect setup for the same amount of $$$.
If I then ignore the pasted strop, I come out ahead of their setup, and I could for example buy a Tony miller strop instead of the pasted / leather loom strop.

Originally Posted by Bruno

For the purpose of stropping it won't matter, though you need a bit of extra flex.
But unlike with a triangular edge, you won't remove any metal by stropping because the edge already is teardrop shaped. Triangular edges become teardrop shaped, so over all the time that you strop that edge, you get 'free' sharpening

But if stropping removes metal from a flat bevel then it also removes metal from a convex bevel. Think about it. If you start with a flat bevel and shave with it for a week then the bevel has already become convex from stropping. The degree of convexity may be less than with the Koordenwinkel method, but it is convex nonetheless. And yet from your argument the strop still removes metal from the bevel.

Now I do think that the more convex the bevel is the slower it abrades the edge, because a relatively flat bevel pressing against the curved surface of the strop applies more pressure to the edge, whereas a curved bevel pressing against the curved strop distributes pressure more evenly across the entire bevel so there is less pressure at the edge. But there seems to be a lower limit to the abrasion speed in practice - once the convexity of the edge matches the curvature of your strop then you're at the limit. All you need to do is make sure that in this situation your strop can still effectively sharpen the razor in a reasonable number of laps each morning. A good abrasive linen linen like the vintage strops used can do this, or you can provide an assist to the modern stuff by using a mild polish like the Dovo white paste, or the 0.1 micron diamond paste, or even the 0.5 micron chromium oxide though you'll probably only need 2-5 laps each morning. I think this is what my great-grandfather used; at least his surviving children and grandchildren claim (1) he only did about 5 laps each morning (2) his strop was a greenish-black color and (3) to the best of their memory didn't own a razor hone, so if he ever honed his razor it was probably done on his knife hone, which was a hard white arkansas now in my possession.

Now I do think that using a dished hone serves no useful purpose. But clearly it can work, if you use a less taut strop. Personally I think a taut strop is easier to learn to maintain than some level of slackness, so I try to keep my hones fairly flat. But I'm not nearly as careful about this as I used to be, and I've noticed that my 1k, 2k, and 4k shaptons (which are all I really use anymore) are noticeably dished nowadays. But if it ever got to the point where I had to use a slack strop because of this I'd lap them in a heartbeat.

Edit: to clarify - I don't think the koordenwinkle method requires you to use a slack strop. This is caused by using excessively dished hones. I don't recommend using dished hones though their technique is certainly more tolerant of dishing than the american method. But the level of dishing Bruno is describing is too much IMO since it affects the stropping.

Originally Posted by Bruno

Maybe it is not a touchup if you define it like that, but it does require me to bring out a hone, which amounts to the same difference. Imo, the time between using anything other than a leather strop should be as long as possible

As that 30's article with the 3000x photos makes clear, you have to abrade the edge a microscopic amount each day to get past the corrosion from the previous day's shave. If the edge is convex enough that you cannot remove the corrosion and resharpen the steel with just the leather, then you have a handful of options.

1. Reset the bevel all the way to flat, which means you need a finishing hone and a decent level of skill.
2. Reset the bevel so it's partly flat without touching the edge, which means you need a cheap medium hone and no honing skill.
3. Increase the abrasiveness of your strop so it can do the job by itself.
4. Use the linen, which is really a variation of option (3) since the linen by itself is more abrasive than leather
5. Use something with a heavier draw like latigo, which is also a variation of option (3)
6. Increase the sag.
7. Increase the pressure. This is something that Scott (honedrite) mentions doing as the blade wears.

I think option (1) is what most people would call a touch up, but I may be wrong. Option (2) may be a touch-up but it is a bevel touch-up not an edge touch-up -- the hone only puts a flat spot on the bevel so the strop will apply more pressure to the edge. And option (3) is frequently called a touch-up as well; the difference is a matter of degree. Is it better to put a great edge on the razor and then let it degrade over a period of weeks or months then hone it back up to snuff again, or is it better to ensure that your daily stropping does just enough honing each day to keep the blade going indefinitely? As that '30's article makes clear the daily stropping does hone the edge, so if the edge is slowly getting dull then it isn't getting enough honing each day from the strop. Personally I like the Dovo white paste on linen for this. The 0.1 micron diamond works well also but loads up too quickly. The Dovo white paste is fairly coarse grit but very soft so it doesn't abrade very quickly and loads up very slowly.

Originally Posted by Bruno

I meant something else.
(and I didn't want to bring this up again ) they consider anything that comes from TI or Dovo to be shaveready. They made that pretty clear.
What I meant was that if a razor has a nick that is only half the size of the bevel width, they consider that razor ready for the junkyard unless you want to send it back to TI or Dovo for regrinding.

Since switching to a variation of their technique I have also found Dovo and TI's to be shave ready, needing only a thorough stropping to deliver a decent shave, although this shave does improve over the next week or so of daily shaving and stropping.

I don't agree with their position on nicks, but then I don't live a few hundred miles from the factories either. I do have some medium grit hones and plenty of time on my hands though. The "plenty of time on my hands" bit is probably the critical factor.

I also don't think you need a stone as fine as a coticule if you use their method. A 4k hone works just fine if you're willing to follow it up with a few more laps on the strop, and I've used it successfully with a 1k stone and with lowly american stones like the soft white arkansas. Once you get over your distaste for convex bevels the extra laps on the strop cease causing concern. Stropping is very easy and very fast compared to the slow delicate strokes on a hone; so if it takes an extra hundred laps on the strop to smooth out a 4k edge that only adds an extra couple of minutes, and is still a heckuva lot faster than even a quick-and-dirty polishing job with a finishing hone.

Originally Posted by Bruno

Our way also doesn't need expensive high grit hones.
I admit I have over 4 digits worth of hones, but that is luxury, not necessity.
I don't use pastes anymore...

The Koordenwinkel method doesn't really need anything as fine or expensive as a coticule; I suspect they use it because the coticule is their local stone. The american method needs either a lot of honing skill acquired through a lot of practice, or expensive high-grit stones, and at least as evidenced on SRP it seems to need both. As you yourself have experienced, this frequently means leaning on pastes while you acquire the skill and hones. The amount of discussion about honing and the number of Shapton, Nakayama, and Escher fans on SRP is some small corroboration of this.

I believe the american honing method (I'll call it that because the guys on B&B and SMF also seem to hone like this) also places an unnecessarily high barrier to success for new shavers. Unnecessary because the Koordenwinkel method achieves the same end with less skill and less expense, and doesn't require a degree of perfection from the razor manufacturers that they are no longer capable of delivering. And it also doesn't require a honemeister to correct the current factory edges so the finicky american honing method can be made to work.

This is the article I keep referring to in my posts above. Or at least it's the post about the article I'm referring to...

I missed this thread from last October. Hurricane Ike flooded my house and made me a refugee of sorts for most of that month. Anyway, I really like this discussion. It reminds me of the ongoing debate in some knife sharpening forums over the relative merits of convex sharpening versus triangular bevels. The convex-fans sharpen knives on slack belt sanders or with sandpaper overlayed on a mousepad. They clain that convex edges are stronger and last longer in heavy use.

Convexed edges for straights is an odd concept for me (with just a couple years experience with straight razors). The whole idea of the spine of the blade being sized to produce the correct bevel angle seems to favor trianglar bevels. You have a mathamatically precise target as a goal; just hone away at both sides until the flat planes intersect. Convexed edges seems more vague. There is no discrete geometric target but instead an infinite number of possible solutions.

Odd how most seem to consider a slack strop to be a bad thing which kills a good edge. Same with heavy pressure on the strop and concaved bench stones. Reading this thread opened my mind to other ways of visualizing the microscopic processes at work.

I will stick to the triangular bevel paradigm which works for me, but I can see there other ways of skinning the cat. (hmmm there is no moticon for cat skinning)

My front door post-Ike!

Good Bump Matt as I enjoyed reading this again.

OK, I give up. What's a Koordenwinkel?

Originally Posted by lawman2

OK, I give up. What's a Koordenwinkel?

sounds like an elf