Chosera stone maintenance

[Phil Pasteur]

A couple of things have come up in discussion lately that I would like to mention before I tell you what I think about this and why. The form a bit of support for my “hypothesis” . I don’t thin you will find a real theory, as a theory is based upon previously proven facts. I have not seen anything other than opinions so far.

First I wanted to bring up a quote that I posted from Sal over at Spyderco. Keep in mind that Spyderco started by making ceramic sharpeners. I will paraphrase as I don’t have the exact quote. He said that all of the ceramics had the same grit and the differences in performance were due to some different binders and diamond texturing.

I also remind folks of the SEM nanographs of steel after stropping. The SEM images of the edge of the edge were pretty amazing. There were sub-micron folds and many different kinds of what perfectionists would call defects.

If we lap a waterstone with something like the 140 Atoma, or the XXC DMT plate we are going to end up with some pretty serious scratches left when we are done. In use those scratches approach the edge of the edge with sharp shoulders from many different directions (depending on the direction used when lapping). I can easily see that this will cause significantly different results than a very flat surface would. Recall the differences in the ceramics that , for instance, Spyderco sells, mostly caused by texturing. Why would the fine waterstones not be affected in a similar fashion. I am not talking about something that would be detected in a 10X loupe. So maybe the effect is not huge, but I think that logically it is something that has to be considered. When you get a stone from Shapton or the Chosera stones, they are very smooth. There are no large scratches to be seen, even at 400X I don’t see scratches in a new stone. I have looked. Can we not assume that this is the way that they intend the stones to be used?

OK, again, maybe this is not something that grossly changes what the stone does, but it is hard to argue that the intent of the manufacturer is not to have the stones used in a quite smooth condition.

So, I think that it is all a matter of how OCD you want to get. If you want to imitate the condition that the stone arrives in as closely as possible, you finish lapping with as fine a grit as is practical.

I am not sure that this gives you an answer that you want to hear Mark, as I know you are trying to decide what (if anything) to buy. The thing is, asking folks like Mark at CKTG or Tom to give a definitive answer is in reality just asking for their opinion. Their opinion will be based on empirical data and long experience, but it is an opinion just the same. What you need to decide is whether the “potential” differences are really important to you. If what you are doing gets you where you want to be, maybe it is good enough.

I think the answers you got on the CKTG forum pretty much indicated that no one was all that concerned about this.

BTW, I am still on the edge about the 400 and 1200 Atoma plates… just because they might be a little better than what I have. This IS an example of compulsive behavior… or at least an addiction to sharpening stuff… The proverbial rabbit hole syndrome..

:woohoo: 👿

So the question is… do you want that Atoma plate… if so grab one. You are the only one that can satisfy yourself as to whether it makes a difference in your edges!! No amount of educated opinions nor logic can give you that answer.

[Ken Buzbee]

I agree with you, Phil, with one additional thought. Before using water stones, I wet them and rub them together. This would pretty much eliminate any differences left from lapping at different grits (within reason 😉 ) If the plates I lap on are rougher than the stone, the stones will be smoothed out. If the plates I lap on are smoother that the stones, it will rough them up.

Using texturing on a ceramic (as per Sal) is if different than the end result on water stones due to the wear..

Ken

[Phil Pasteur]

I agree with you, Phil, with one additional thought. Before using water stones, I wet them and rub them together. This would pretty much eliminate any differences left from lapping at different grits (within reason 😉 )

Within reason is the key phrase… The Atoma 140 is pretty coarse though, as is the DMY XXC. The scratches from these (at least my XXC) last a good while, even with rubbing the stones before use. That fact was why I bought several finer grit plates to use after lapping with the coarse plate.

If the plates I lap on are rougher than the stone, the stones will be smoothed out. If the plates I lap on are smoother that the stones, it will rough them up

Isn’t this just the opposite of what happens ???

Using texturing on a ceramic (as per Sal) is if different than the end result on water stones due to the wear..

Over time this is true, the waterstones will lose any texture much faster than the ceramic stones,but the point was only that texturing makes a difference at that edge.

[Ken Buzbee]

If the plates I lap on are rougher than the stone, the stones will be smoothed out. If the plates I lap on are smoother that the stones, it will rough them up

Isn’t this just the opposite of what happens ???

I struggled with the wording on that and still blew it. 😉 More coffee was needed. The edited version, “If the plates I lap on are rougher than the stone, the stones will be smoothed out when they are rubbed together. If the plates I lap on are smoother that the stones, it will rough them up when they are rubbed together

Using texturing on a ceramic (as per Sal) is if different than the end result on water stones due to the wear..

Over time this is true, the waterstones will lose any texture much faster than the ceramic stones,but the point was only that texturing makes a difference at that edge.

I’ll trust you on that. I haven’t tried lapping with the coarsest plates but the ones I have used didn’t (that I could discern) leave any residual texturing.

Ken

[Jende Industries]

Tom,

In your video you use a 600 grit Atoma for your 10K Shapton and a 1200 grit Atoma for your 10K Chosera. (If I remember it correctly – saw the video this morning.) Is there a reason for this?

If you could buy only one Atoma for flattening your high-grit stones, which one would it be?

Sorry guys – I’ve been busy!

The reason I use the different plates is to texture the surface of the stones to enhance their performance. Phillip explained it quite well. B) It does change the way the stone feels aggressiveness-wise, and I have seen differences in the finishes. I mentioned the 600 stock in the video because it is a diamond plate every WEPS user will have, but used the 1K WEPS diamond.

Also, you don’t need to use several lapping plates, but when you start getting involved in the WEPS sports more, it becomes useful. If I had to recommend only one lapping plate, it would be the 600. That will lap almost the entire range of Choseras, and leaves the “second best” finish on the 10K in particular. FWIW, I use the following lapping progression:

400, 600, 800, 1K – Atoma 140
1,500, 2K – Atoma 400
3K, 5K – Atoma 600
8K, 10K, 12K, 15K, 16K, 30K – 1,200 Atoma

[Johpe]

What happened to lapping them on the WEPS diamond plates? I saw a video on YouTube where I think you were doing just that?

[Jende Industries]

Right – That was in this video. I lapped them on the WEPS diamonds to show how to do it, but also used the full size Atomas to show how to lap with them as well.

I sharpen quite a few things, so I am in the habit of flattening my stones at least after every session, and sometimes even after every couple of knives if I feel it is necessary. The slight dishing at the lower end of the Choseras (or compounded dishing throughout a progression), however minor, can cause the 10K to “miss” the edge of the edge. I am also very OCD when it comes to using my WEPS, too. (because I can!!) 👿

For more casual users, lapping is still necessary, although probably not as often.

The nagura stones that come with the full size Choseras are approx 600 grit, and are quite useless, IMO – especially if you have several full size Chosera stones since all grits come with the same 600 grit nagura! They are meant as cleaning stones to help keep dishing to a minimum, but no one I know uses them for that. I tried, and I don’t feel it’s worth the effort, except maybe on the 600 Chosera 🙂

You can get slurry stones for the Choseras (if you’re interested, let me know), which are small pieces of the same grit, but you can get that on the WEPS simply by rubbing the 2 paddles together. If you leave the white slurry that forms, the stones will be more aggressive, since it is loose abrasive particles, but if you rinse it off, it will be textured, although not necessarily at the same grit as the stone.

[Mark76]

The reason I use the different plates is to texture the surface of the stones to enhance their performance. […]I have seen differences in the finishes.

Tom, I’m really intrigued by this. At “the” other forum, Ken wrote in a discussion on the same subject:

I haven’t read Tom’s posts there (and should) but somehow transferring stone scratches to knife edge scratches doesn’t sound right – even from Tom (We quibble all the time about sharpening theory.)

The key question to me is: can scratches on a stone transfer to the edge. It seems you say “yes” and Ken says “no”. How come? Who’s right? (Obviously you are right. I can’t see it through my microscope, but I feel it 😉 And I cannot imagine how scratches in abrasive stuff such as a sharpening stone would not transfer to the edge.).

Can you comment on that?

Ken, Phil, it’s not just a matter of OCD for me and “if you like the feel of a nicely textured stone, get the plate”. It’s also the scientist in me who wants to know exactly how it works.

Molecule Polishing: my blog about sharpening with the Wicked Edge

[Phil Pasteur]

Ken, Phil, it’s not just a matter of OCD for me and “if you like the feel of a nicely textured stone, get the plate”. It’s also the scientist in me who wants to know exactly how it works.

Scientists “prove” things by experimentation. You need to get some plates and conduct first hand experiments… Maybe you can get a grant or a sponsor..
👿 :silly:

I am pretty sure you will not satisfy your quest for understanding by asking for opinions..
Especially when, as we have seen, the experts either don’t agree, or don’t care.

[wickededge]

I am pretty sure you will not satisfy your quest for understanding by asking for opinions..
Especially when, as we have seen, the experts either don’t agree, or don’t care.

I don’t have the level of experience with the Chosera stones that Ken and Tom have – those guys have been at it for a long time. I like the idea of setting up an experiment, should be easy enough to do if one has the time, I’ve been short on that lately… Once we get into our new space and I can set up a better R&D area, I can do more experimenting again. I’ve been consumed with design and production for the last 6 months.

-Clay

[Jende Industries]

I have seen differences in the finishes.

Mark – I should’ve added “at the macro level” (I actually did type that initially…) The finish, particularly off the Shapton 8K and 15K, is much cleaner and shinier at the macro level after using the Atoma 1200 to lap them. The Choseras are a little different because they eventually polish anyway, so the longer you use them, the better the finish.

At the micro level, the only main difference I’ve seen is the cleanliness you can achieve, and this is (IMO) more a direct product of the “critical leap”, which is on the 2K-5K on the Shaptons and the 5K-10K on the Choseras. With this in mind, I lap the 5K stones on the 600 Atoma to keep some more of that aggression so that they do a good job cleaning up.

Overall, I think the Shaptons benefit more from the different lapping grits, but it has carried over to both series for me.

Phillip, I wouldn’t say experts don’t care, but it is more a matter of sometimes having a professionally formed opinion that isn’t really worth debating too much 🙂 After all, everything about sharpening is highly subjective!

[Phil Pasteur]

Phillip, I wouldn’t say experts don’t care, but it is more a matter of sometimes having a professionally formed opinion that isn’t really worth debating too much After all, everything about sharpening is highly subjective!

Tom,
For clarity. Mark had asked the same question on other forums. The responses “in general” were that the lapping issue was not a concern… People again, in general thought that whatever it was that they were currently doing was fine. I did not at all mean that you or Ken did not care. The statement could have been stated much more clearly, I admit. Perhaps stating, Ken and Tom seem to disagree and others that have been consulted seem to not care one way or another
would have better expressed what I was trying to get across.

I wrote Mark a PM, before I saw your response here, hopefully clarifying what I actually meant.

Sorry for any lack of clarity on my part!

Of course, the part about it all being highly subjective is something that I agree with and part of the point I was trying to convey to Mark.

[Matt Cole]

Where can I buy a base to hold the full size Atoma plates?

[Phil Pasteur]

http://www.woodcraft.com/product/2003115/1667/stone-holders.aspx
OR
http://www.chefknivestogo.com/nastho.html
I got one like the ones above for about $15 from Amazon or Ebay… can’t remember which.
There are lots of different types at lots of price levels. The one I have works fine.

Search for “universal stone holder” or variations. You will find many…

[Matt Cole]

Thanks

[Author]

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