I needed a course stone for getting a quick burr. I got the Suehiro cerax, large brick. Made life easier for me. I'm learning to sharpen knives on stones, finally getting consistent results.
Cliff: I think you may have solved a long standing riddle for me. I am really glad you did this video. For years I have sharpened different steels on either diamond stones, natural stones, or waterstones and of course Norton stones because experience taught me that a specific stone worked best on a specific steel all this time I should have been looking at not only the stone I was using but the pattern it produces on a given steel and the medium I use to float the slurry, water, oil, windex, simple green, etc and how that and the slurry affect the pattern. I recently noticed this on an old waterstone I was given at ten thousand grit. It was terrible until I lapped it on a diamond stone and cleaned it up I realized that the owner had left it in water so much that the outer layer of binder was completely broken down and as soon as you tried to use it the knife would just dig into that until it hit the harder matrix below. Once I removed the damaged layer it began to work quite well again. I am going to have to re-visit all my waterstones under magnification. You are quite right I am not sure how you would express this short of doing a writeup for each stone you use and how you use it (surface prep, soak time, etc.).
Yeah that is one of the problems with a lot of waterstones, especially the new ones which they are making non-soak. If you do soak them they can get a very soft and gummy layer on top which behaves just like you noted. It is becoming apparent to me that stones are like knives/steels, there is a lot more to them than people think and making some kind of evaluation of them isn't that trivial as they can excel when used in one way and fail horribly if used in another. But making some kind of general statement isn't always sensible. Is a fillet knife "bad" as it doesn't chop up 2x4 quickly? Obviously no. But in the same way a stone might not be bad simply because it doesn't grind well under heavy force with lots of water because it was designed to cut well with low force with just a little water on a different type of steel.
Sigma power 6000 behaved the same way for me using it for woodworking blades. After dressing it with an atoma 400, it has become my favorite middle stone for all types of steel even HSS.
Yeah, if I didn't care about money/cost, I would likely just use the Sigma Power Select II stone, with diamond plates to finish/apex for the knives using coarse edges.
so, how do you actually like it? it semms pretty interesting on the bit about the scratch patterns it leaves. it's amazing the difference in performance of stones and steels are so much similar in that aspect. i am looking forward to picking up a couple new stone in a few months. i look forward to trying something new. i'm really leaning towards a sigma power select stone both low and high grit. if what you say about the pricing on this stone, i may get one sooner than later, sounds pretty affordable.
I've been wondering how you calculate the amount of pressure you put on stones while sharpening or into cuts during cut testing. Do you apply pressure to a scale, then try very hard to apply the same amount of pressure to the work? I've been thinking that while this is far more repeatable than most techniques, it'll still leave you with quite a bit of variation in your results. Have you thought about making a jig system to do cut tests as repeatably as possible? As a maker I'd find this pretty interesting. I'd also be willing to make blades specifically designed for that sort of jig in a number of different steels. Unrelated, but worth mentioning, I really enjoy your videos and have been trying to work a number of techniques and design elements you talk about into my knives. Thanks!
Mitchell Sheppard I measure the force applied on a scale and then calculate the pressure from the contact area. The major source of the spread isn't the force but the contact area. As you move the stone along the blade, especially as it moves into the belly, then the edge length can easily change by by more than 2:1, in fact even 4:1 is possible. This is why the pressure ranges I quote are quite large and represent the average spread. In regards to cutting I do similar in regards to force applied and also measure speed (time and distance are easily measured). These have a small random effect but it isn't significant because remember I am averaging over very long cut cycles, 1000+ cuts is common even in short trials. The average behavior is quite stable because of statistical rules such as the law of large numbers.
It is much faster, more than 2:1, but it is also much more coarse. I know Carter likes then King 1000 for rough work but something like the Suehiro 'Chemical' is the minimum I would want and unless I am playing around I would drop down to the coarse India, Sigma Power 120, TASK, etc. . for any significant shaping. They are faster than the Suehiro by the same amount it is over the King.
I purchased this stone for about $30 in hast looking for something to fill the void of my limited stone collection. It was all that I could find locally that was marketed to fit the bill for what I was looking for that day. I really don't know much about it but I'm happy to hear that it is rated as much softer than an 800 grit stone. I'm almost thinking that I should invest in three quality diamond plates and forget about all this experimenting to find a system for working with as apposed to testing, exploring and being able to educate others. Cliff, does a system come to mind that you would recommend for a one time investment, forever, get the work of sharpening done and use the the tool kind of system? Or in other words- if you were trapped on a dessert island and had a a few pieces of your airplane strewn about and found a sharpening system in a small suitcase, what would it be? Please don't say a bastard file and an old Coke bottle, lol. As for the Suehiro #800, I feel like it will take some time to know, it does seem to change in it's character a lot but I find it needs a very good soaking (more than 10 minutes, closer to 30 minutes) or it absorbs water so quickly its too dry to work with. Thanks for sharing your experience with it.
Ha Ha Ha, I've collected a few folders with on average 3.25" blades- VG10, S30V, Aus8a, CTS BD1, 8CR14Mov and one 1095 Tops "Cuma Hiss" neck knife which I carry on my life jacket at work with a reverse curve that I find a bit of a challenge to sharpen well, but after some moderate reprofiling with a coarse diamond file at 15 degrees it's getting a bit easier to address with the sharpmaker or with an economy four sided diamond plate block. So mostly EDC folders and one enjoyable yet challenging high carbon utility knife.
Jeff Smith Jeff, Norton Crystolon. This is a strong bond stone, still a little friable and can take very high forces/pressures without excessive wear. Use with a light oil (baby oil or similar). It will work well on the steels you describe. The fine side is still fairly coarse, nice for slicing but poor for push cutting. If you want to do more push cutting, carving woods, chopping/dicing foods, then a Soft Arkansas is a nice stone to add a much higher polish micro-bevel, using the Norton to remove any damage and reset the edge as required. You can use the Norton to recondition the Arkansas periodically as it will just wear as it won't release abrasive. If you don't condition one side it will eventually just keep getting much finer still so it can easily reach the polish ability of very fine stones like the Spyderco white and similar razor level stones.
Are the initial grit particles similar in size between the two stones before the mud forms? Is the naniwa more friable? Also do they maintain their aggressive cutting speed w the thick mud?
Yes, they are similar in size in the stone as viewed under 50x magnification. Yes, they maintain high cutting speed with the mud. I believe all it does it generate side grinding through movement of the abrasives in the mud/slurry. Here is the concern - what exactly do you mean by friable? Is the binder easy to break or is the abrasive easy to break?
Cliff Stamp Dang, youz be up early man. I thought friable meant the abrasive itself fractures easily? I was thinking of the shots of the grit in the mud you posted and how the particles in the Naniwa mud seemed smaller ( friable) and so could "roll" over each other better (at least I think that's what you were saying). My wondering was if the abrasive being easy to break also reduced cutting efficieny as the mud formed? Or is there large pieces of grit released at the same time to keep the cutting efficiency high?
C amber Ha, when did you think I did all of that cutting. Friable in industry can mean abrasive (silicon carbide is very friable compared to aluminum oxide) but it can also refer to the bulk abrasive as in very friable wheels release fresh abrasive quickly while non-friable wheels need to be dressed to prevent glazing. I think the Naniwa abrasive is breaking down and either getting smaller or getting to a particular shape (or has one) which allows more lateral movement. I just can't see this with traditional microscopes because of field of depth issues. I have been playing with focus stacking but even then it isn't clear. I think I can maybe look at it by just mixing some of the dried slurry into a fluid and watching how it disperses. If I am correct the Naniwa will disperse much faster/wider than the Suehiro which will tend to just sink faster. In general the only way you will really see the mud slow down the cutting is if you let the stone dry out so the mud masks the abrasive.
Cliff Stamp You know I wasn't sure...for all your love for science there does seem to be some sort of voodoo with how much you get done in a day...must have 26 hours up there in Canada. Thanks for the clarification on friable...seems like there should be two different terms used for clarity, but surprisingly few industry experts consult with me... You really have me wanting to pick up a Suehiro (and a Sigma 120), but I have to get over the shipping shock.
C amber The issue is that while we may care in industry the main focus is on what happens, not why it happens. If a wheel releases fresh abrasives constantly because the binder is breaking or it does because the abrasive is breaking the net effect is very similar - an aggressive, self-sharpening, non-glazing surface. If you are a guy who is grinding a piece of steel what really do you want to know - some internal characteristic of the abrasive or how it actually behaves when you jam the steel into it?
The initial performance is likely to cause some issues if they are all like the one I had. When you get past that it is a solid coarse stone. Now as for a beginner I would ask first what are they sharpening, in general waterstones as much as I use them are not ideal for a lot of steels. If the steels are simple then a standard India stone is a very nice abrasive. If you take a look at videos, a lot of people will let stones get really out of flat. When this happens the edge bevels start to vary and unless you account for that you will have problems when you jump grits. Then you add to that the complexity of how the mud affects how the stone forms the edge. If you don't adjust for that in your technique you can be frustrated as well. In general I would recommend using a coarse/fine india on simple steels until you have a solid understanding of sharpening. Then the waterstones can allow much faster grinding and you will be able to deal with the additional complexity they put into the process. If you try it all at once you can end up being very frustrated. But as for this stone, it is half the price of a Norton/King, it is hard to say not to get it if you want a decent coarse waterstone in this range. The only thing I would note is that softer stones are pressure sensitive. If you really like to lean into stones hard then this stone could be a frustration.
Cliff, thank you for the detailed response. I for some reason I thought "this is a japanese india stone" when you first started talking about this. I look forward to seeing how this stone continues to play out. On the aside, has the Yanagiba improved at all?
Bill22252 I just ran it on this stone and will put up pictures later, still has a lot of damage though. I might break out one of the UC stones this weekend as I just picked up another one. The Sigma Power 120 is likely to chew through the remaining damage itself.
C amber 24 grit, designed to recut grinding wheels when they glaze. I bought it to see if it could be used to recut the Sigma Power 120 and just for kicks. It looks identical to the "King Tiger Rough Sharpening Stone". I bought it when I bought the 70+ pile of stones from Congress Tools.
RIP Cliff 🙌🏼😔
I needed a course stone for getting a quick burr. I got the Suehiro cerax, large brick. Made life easier for me. I'm learning to sharpen knives on stones, finally getting consistent results.
Cliff: I think you may have solved a long standing riddle for me. I am really glad you did this video. For years I have sharpened different steels on either diamond stones, natural stones, or waterstones and of course Norton stones because experience taught me that a specific stone worked best on a specific steel all this time I should have been looking at not only the stone I was using but the pattern it produces on a given steel and the medium I use to float the slurry, water, oil, windex, simple green, etc and how that and the slurry affect the pattern. I recently noticed this on an old waterstone I was given at ten thousand grit. It was terrible until I lapped it on a diamond stone and cleaned it up I realized that the owner had left it in water so much that the outer layer of binder was completely broken down and as soon as you tried to use it the knife would just dig into that until it hit the harder matrix below. Once I removed the damaged layer it began to work quite well again. I am going to have to re-visit all my waterstones under magnification. You are quite right I am not sure how you would express this short of doing a writeup for each stone you use and how you use it (surface prep, soak time, etc.).
Yeah that is one of the problems with a lot of waterstones, especially the new ones which they are making non-soak. If you do soak them they can get a very soft and gummy layer on top which behaves just like you noted. It is becoming apparent to me that stones are like knives/steels, there is a lot more to them than people think and making some kind of evaluation of them isn't that trivial as they can excel when used in one way and fail horribly if used in another. But making some kind of general statement isn't always sensible. Is a fillet knife "bad" as it doesn't chop up 2x4 quickly? Obviously no. But in the same way a stone might not be bad simply because it doesn't grind well under heavy force with lots of water because it was designed to cut well with low force with just a little water on a different type of steel.
Sigma power 6000 behaved the same way for me using it for woodworking blades. After dressing it with an atoma 400, it has become my favorite middle stone for all types of steel even HSS.
Yeah, if I didn't care about money/cost, I would likely just use the Sigma Power Select II stone, with diamond plates to finish/apex for the knives using coarse edges.
so, how do you actually like it? it semms pretty interesting on the bit about the scratch patterns it leaves. it's amazing the difference in performance of stones and steels are so much similar in that aspect. i am looking forward to picking up a couple new stone in a few months. i look forward to trying something new. i'm really leaning towards a sigma power select stone both low and high grit. if what you say about the pricing on this stone, i may get one sooner than later, sounds pretty affordable.
Yeah, it is a really solid stone for the price assuming you are willing to work with a softer/muddy stone.
I've been wondering how you calculate the amount of pressure you put on stones while sharpening or into cuts during cut testing. Do you apply pressure to a scale, then try very hard to apply the same amount of pressure to the work? I've been thinking that while this is far more repeatable than most techniques, it'll still leave you with quite a bit of variation in your results. Have you thought about making a jig system to do cut tests as repeatably as possible? As a maker I'd find this pretty interesting. I'd also be willing to make blades specifically designed for that sort of jig in a number of different steels. Unrelated, but worth mentioning, I really enjoy your videos and have been trying to work a number of techniques and design elements you talk about into my knives. Thanks!
Mitchell Sheppard I measure the force applied on a scale and then calculate the pressure from the contact area. The major source of the spread isn't the force but the contact area. As you move the stone along the blade, especially as it moves into the belly, then the edge length can easily change by by more than 2:1, in fact even 4:1 is possible. This is why the pressure ranges I quote are quite large and represent the average spread.
In regards to cutting I do similar in regards to force applied and also measure speed (time and distance are easily measured). These have a small random effect but it isn't significant because remember I am averaging over very long cut cycles, 1000+ cuts is common even in short trials. The average behavior is quite stable because of statistical rules such as the law of large numbers.
Interesting. Thanks.
I know your testing isn't complete, but how would you compare this to something like the King 1000 in terms of cutting speed?
It is much faster, more than 2:1, but it is also much more coarse. I know Carter likes then King 1000 for rough work but something like the Suehiro 'Chemical' is the minimum I would want and unless I am playing around I would drop down to the coarse India, Sigma Power 120, TASK, etc. . for any significant shaping. They are faster than the Suehiro by the same amount it is over the King.
Thanks 👌
60 Rockwell?
I purchased this stone for about $30 in hast looking for something to fill the void of my limited stone collection. It was all that I could find locally that was marketed to fit the bill for what I was looking for that day.
I really don't know much about it but I'm happy to hear that it is rated as much softer than an 800 grit stone. I'm almost thinking that I should invest in three quality diamond plates and forget about all this experimenting to find a system for working with as apposed to testing, exploring and being able to educate others. Cliff, does a system come to mind that you would recommend for a one time investment, forever, get the work of sharpening done and use the the tool kind of system? Or in other words- if you were trapped on a dessert island and had a a few pieces of your airplane strewn about and found a sharpening system in a small suitcase, what would it be? Please don't say a bastard file and an old Coke bottle, lol.
As for the Suehiro #800, I feel like it will take some time to know, it does seem to change in it's character a lot but I find it needs a very good soaking (more than 10 minutes, closer to 30 minutes) or it absorbs water so quickly its too dry to work with.
Thanks for sharing your experience with it.
Jeff Smith Jeff, can I say Jessica Alba carrying a file and coke bottle?
What kinds of steels do you normally sharpen?
Ha Ha Ha,
I've collected a few folders with on average 3.25" blades- VG10, S30V, Aus8a, CTS BD1, 8CR14Mov and one 1095 Tops "Cuma Hiss" neck knife which I carry on my life jacket at work with a reverse curve that I find a bit of a challenge to sharpen well, but after some moderate reprofiling with a coarse diamond file at 15 degrees it's getting a bit easier to address with the sharpmaker or with an economy four sided diamond plate block. So mostly EDC folders and one enjoyable yet challenging high carbon utility knife.
Jeff Smith Jeff,
Norton Crystolon. This is a strong bond stone, still a little friable and can take very high forces/pressures without excessive wear. Use with a light oil (baby oil or similar). It will work well on the steels you describe. The fine side is still fairly coarse, nice for slicing but poor for push cutting.
If you want to do more push cutting, carving woods, chopping/dicing foods, then a Soft Arkansas is a nice stone to add a much higher polish micro-bevel, using the Norton to remove any damage and reset the edge as required.
You can use the Norton to recondition the Arkansas periodically as it will just wear as it won't release abrasive. If you don't condition one side it will eventually just keep getting much finer still so it can easily reach the polish ability of very fine stones like the Spyderco white and similar razor level stones.
Thanks Cliff.
Are the initial grit particles similar in size between the two stones before the mud forms? Is the naniwa more friable? Also do they maintain their aggressive cutting speed w the thick mud?
Yes, they are similar in size in the stone as viewed under 50x magnification.
Yes, they maintain high cutting speed with the mud. I believe all it does it generate side grinding through movement of the abrasives in the mud/slurry.
Here is the concern - what exactly do you mean by friable? Is the binder easy to break or is the abrasive easy to break?
Cliff Stamp Dang, youz be up early man.
I thought friable meant the abrasive itself fractures easily? I was thinking of the shots of the grit in the mud you posted and how the particles in the Naniwa mud seemed smaller ( friable) and so could "roll" over each other better (at least I think that's what you were saying). My wondering was if the abrasive being easy to break also reduced cutting efficieny as the mud formed? Or is there large pieces of grit released at the same time to keep the cutting efficiency high?
C amber Ha, when did you think I did all of that cutting.
Friable in industry can mean abrasive (silicon carbide is very friable compared to aluminum oxide) but it can also refer to the bulk abrasive as in very friable wheels release fresh abrasive quickly while non-friable wheels need to be dressed to prevent glazing.
I think the Naniwa abrasive is breaking down and either getting smaller or getting to a particular shape (or has one) which allows more lateral movement. I just can't see this with traditional microscopes because of field of depth issues. I have been playing with focus stacking but even then it isn't clear.
I think I can maybe look at it by just mixing some of the dried slurry into a fluid and watching how it disperses. If I am correct the Naniwa will disperse much faster/wider than the Suehiro which will tend to just sink faster.
In general the only way you will really see the mud slow down the cutting is if you let the stone dry out so the mud masks the abrasive.
Cliff Stamp You know I wasn't sure...for all your love for science there does seem to be some sort of voodoo with how much you get done in a day...must have 26 hours up there in Canada.
Thanks for the clarification on friable...seems like there should be two different terms used for clarity, but surprisingly few industry experts consult with me...
You really have me wanting to pick up a Suehiro (and a Sigma 120), but I have to get over the shipping shock.
C amber The issue is that while we may care in industry the main focus is on what happens, not why it happens. If a wheel releases fresh abrasives constantly because the binder is breaking or it does because the abrasive is breaking the net effect is very similar - an aggressive, self-sharpening, non-glazing surface. If you are a guy who is grinding a piece of steel what really do you want to know - some internal characteristic of the abrasive or how it actually behaves when you jam the steel into it?
Station effect 👍
How about "scratchy" as a term for the metric you describe in this vid?
+Sasha Quaich Not sure what you are talking about exactly.
Interesting stone. Do you think this might be a better option for the neophyte waterstone user than something like the King.
The initial performance is likely to cause some issues if they are all like the one I had. When you get past that it is a solid coarse stone. Now as for a beginner I would ask first what are they sharpening, in general waterstones as much as I use them are not ideal for a lot of steels. If the steels are simple then a standard India stone is a very nice abrasive.
If you take a look at videos, a lot of people will let stones get really out of flat. When this happens the edge bevels start to vary and unless you account for that you will have problems when you jump grits. Then you add to that the complexity of how the mud affects how the stone forms the edge. If you don't adjust for that in your technique you can be frustrated as well.
In general I would recommend using a coarse/fine india on simple steels until you have a solid understanding of sharpening. Then the waterstones can allow much faster grinding and you will be able to deal with the additional complexity they put into the process. If you try it all at once you can end up being very frustrated.
But as for this stone, it is half the price of a Norton/King, it is hard to say not to get it if you want a decent coarse waterstone in this range. The only thing I would note is that softer stones are pressure sensitive. If you really like to lean into stones hard then this stone could be a frustration.
Cliff, thank you for the detailed response. I for some reason I thought "this is a japanese india stone" when you first started talking about this. I look forward to seeing how this stone continues to play out.
On the aside, has the Yanagiba improved at all?
Bill22252 I just ran it on this stone and will put up pictures later, still has a lot of damage though. I might break out one of the UC stones this weekend as I just picked up another one. The Sigma Power 120 is likely to chew through the remaining damage itself.
Cliff Stamp Ohhh, what's the new UC stone?
C amber 24 grit, designed to recut grinding wheels when they glaze. I bought it to see if it could be used to recut the Sigma Power 120 and just for kicks. It looks identical to the "King Tiger Rough Sharpening Stone". I bought it when I bought the 70+ pile of stones from Congress Tools.