You can never be too careful!
Raising burr of every stone vs. only once
- Thread starter WaTFTanaki
- Start date
Help Support Kitchen Knife Forums:
FWIW, the ultimate version of this is @Kippington's method. He pushes the burr way over to one side using a high angle stroke, then does an edge leading (still somewhat high angle) stroke to fold it over and cut/abrade it off.
I remember a vid where you use an "edge following" horizontal stroke for deburring. Is that still an integral part of your routine?
Grayswandir
Senior Member
Interesting stuff.
I've only recently entered into the world of Japanese knives and Japanese water stones. Before this, I would sharpen knives on cheap stones, usually oil stones (I used transmission fluid because that's what I had lying around) and not very often. My knives would get sharp, but never to the degree that I really wanted. Since purchasing some good knives and good Japanese stones (I guess good is relative, as some stones are inexpensive and work very well, while others are very expensive, and I imagine work very well also), I'm really shocked at how sharp my knives get now. I don't think I really understood what sharp really meant until I started my journey into Japanese steel and water stones.
I class myself as an amateur when it comes to sharpening, but thus far, I'm happy with the results I'm getting. I didn't notice anyone bringing up Murry Carter's method of deburring using a piece of wood? Someone did make a brief mention of using cork, but I wanted to mention wood, which is what I tried recently on my newest knife. I basically let the weight of the knife do the job for me, and passed the edge over a piece of particle board (my desk actually, it's old and there's a nice sized divot on the edge that faces me). It seemed to work really well. There was no more burr, and I moved onto my 6K stone to finish things up.
I used a nagura stone to create a slurry (it was an 8K nagura stone), thinking the finer grit would help polish and refine my edge. It seemed to work pretty well, or at least I think it worked pretty well. I don't really have enough experience to know for sure, since it's the first time I tried it. I also stropped using the pad of my hand like the other fellow, I read something about it not very long ago and figured I'd give it a try.
I finished things off with trailing strokes, and the edge has held up well so far, the blade is wicked sharp. Also, I'd appreciate any advice someone is willing to give in regards to my use of that 8K nagura stone. I know nagura stones are used to clean stones, but I've also read that the finer nagura stones can be used to raise a slurry and help polish the edge as well.
I've only recently entered into the world of Japanese knives and Japanese water stones. Before this, I would sharpen knives on cheap stones, usually oil stones (I used transmission fluid because that's what I had lying around) and not very often. My knives would get sharp, but never to the degree that I really wanted. Since purchasing some good knives and good Japanese stones (I guess good is relative, as some stones are inexpensive and work very well, while others are very expensive, and I imagine work very well also), I'm really shocked at how sharp my knives get now. I don't think I really understood what sharp really meant until I started my journey into Japanese steel and water stones.
I class myself as an amateur when it comes to sharpening, but thus far, I'm happy with the results I'm getting. I didn't notice anyone bringing up Murry Carter's method of deburring using a piece of wood? Someone did make a brief mention of using cork, but I wanted to mention wood, which is what I tried recently on my newest knife. I basically let the weight of the knife do the job for me, and passed the edge over a piece of particle board (my desk actually, it's old and there's a nice sized divot on the edge that faces me). It seemed to work really well. There was no more burr, and I moved onto my 6K stone to finish things up.
I used a nagura stone to create a slurry (it was an 8K nagura stone), thinking the finer grit would help polish and refine my edge. It seemed to work pretty well, or at least I think it worked pretty well. I don't really have enough experience to know for sure, since it's the first time I tried it. I also stropped using the pad of my hand like the other fellow, I read something about it not very long ago and figured I'd give it a try.
I finished things off with trailing strokes, and the edge has held up well so far, the blade is wicked sharp. Also, I'd appreciate any advice someone is willing to give in regards to my use of that 8K nagura stone. I know nagura stones are used to clean stones, but I've also read that the finer nagura stones can be used to raise a slurry and help polish the edge as well.
Kawa
Senior Member
Something I still dont quite get,
Where is the difference between 'stropping on a little higher angle as where you were sharpening' and 'you ruined your edge due to too high angle stropping'.
Maybe its the same question as in the difference between a microbevel and hitting too high angle and ruin al you work done before..
I think its a small nuance, but maybe one can put it into words..
Where is the difference between 'stropping on a little higher angle as where you were sharpening' and 'you ruined your edge due to too high angle stropping'.
Maybe its the same question as in the difference between a microbevel and hitting too high angle and ruin al you work done before..
I think its a small nuance, but maybe one can put it into words..
Maybe they're talking about having an inconsistent angle along the length of the edge? Like if you screw up your edge leading strokes by lifting your hand a whole bunch at the tip or something? My most common error is lifting my hand too much when dealing with a knife with a super flat profile and having the edge of the knife run along the edge of the stone.
Personally, I'm not sure why everyone seems to think leading strokes are so much harder to execute than trailing strokes. Maybe it’s more obvious when you screw up the angle, since you can have the edge dig into the stone? Or maybe people don’t flatten their stones? If you have a concavity in the stone, that can make it more likely for the edge to dig in.
One thing that helps me is that I always have a finger of one hand contacting the edge and the stone as a guide:
Personally, I'm not sure why everyone seems to think leading strokes are so much harder to execute than trailing strokes. Maybe it’s more obvious when you screw up the angle, since you can have the edge dig into the stone? Or maybe people don’t flatten their stones? If you have a concavity in the stone, that can make it more likely for the edge to dig in.
One thing that helps me is that I always have a finger of one hand contacting the edge and the stone as a guide:
Luftmensch
Senior Member
- Joined
- Dec 13, 2017
- Messages
- 2,316
- Reaction score
- 3,186
As others have said, the best method is the one that works for you. Although that might sound frustratingly vague (everybody is a winner), you need to build up muscle memory and technique. You will get better results if you pursue a method that feels less awkward. As you gain confidence and control, you will find experimenting with other techniques easier.
Forming a burr is generally evidence you have removed enough steel from both sides to form an apex. In an ideal situation, you only need to do this once. Theoretically there is no need to do it on each stone. As you move up the grits, you are refining the scratch pattern on the bevel so the edge becomes less ragged. You are not attempting to join/apex the bevels - you have already done this!
But take a few steps back. Do you even need to form a burr? If you are using a burr as evidence you have completed a step and can move to the next step, I would recommend using other methods. For example, the three finger test - it is a more general method for judging your progress. If you are doing maintenance sharpening because the edge is "ok but not amazing", you probably don't need to reform a burr. Use the three finger test instead. If you are sharpening a high hardness and wear resistant steel, it might not want to produce a stonking great burr like softer steels. Again... use the three finger test!
Grayswandir
Senior Member
Would you consider the paper test to be an accurate way to measure sharpness vs. the 3 finger test? If the blade cuts through paper cleanly, you should be good to go, no? You can also test every area of the edge, from heel to tip, using paper.
Paper won't really tell you how sharp it is. Just it's sharp enough, sharp along the edge and the feedback from the sound let's you know the burr is removed.
Grayswandir
Senior Member
If the blade is really sharp, the cut will be clean. A duller knife cuts the paper differently, it leaves behind a jagged cut. I've never listened for burr removal, to be honest, didn't even know that was a thing. I did listen to an older Japanese gentleman talk about listening to the stone and how it sounds while you're sharpening, but that was more about being consistent with your technique, you can hear changes with more or less pressure, speed, etc. I'll have to try and listen for burr removal next time I sharpen. Should be interesting.
It's really the sound will be a little different, cut not as smooth and can't cut circles if the apex isn't fully deburred and formed. Not anything dramatic, just something if you're paying attention you'll notice.
Try fully deburring half the knife then cut paper.
I only really started paying attention to this a few months ago. It's a good idea. Prevents you from having to test for burrs on other media as much.
Grayswandir
Senior Member
I was speaking more to sharpness in general, but I imagine a half deburred knife edge wouldn't cut very well, or would it?
I think he means you'll feel and hear the difference as your cut transitions from the deburred half to the undeburred half.
Grayswandir
Senior Member
It makes me think of Jim Carry in the In Living Color Days, when he pulls a gun on the old kung-fu master, "Just give me the stone old man!"
He could be trying to trick me.
He could be trying to trick me.
Well, ok, but you're still trying to hit the edge, no? Raising a subtle burr is a good way to verify that you're not just polishing the shoulder of the previous bevel. If it's a big initial bevel, you can feel when you're polishing it correctly, but sometimes with really small bevels it's hard to distinguish by feel whether you're hitting the bevel or the shoulder.
Maybe I should try doing that more often. I use the three finger test, but mostly toward the end of the session to check on burr removal rather than earlier on. A burr is stupid easy to feel and verify, though, which makes it attractive...
Mostly agree with this.
matchplay18
Banned
- Joined
- Sep 4, 2018
- Messages
- 264
- Reaction score
- 317
Great thread I have been sharpening knives over 30yrs. Find the best multiple sources you can to learn the fundamentals. From there you come into your own. For the greenhorn and newcomer this thread is invaluable. The nuances are infinite. For most people the biggest problem is to practice practice practice until it becomes this innate ability setting that blade is a kinetic sense. So far I have reinforced and learned a few new things
mpier
Senior Member
I would agree with just about everything said here, practice all the techniques you can and add them to your arsenal. There are so many different shapes and sizes of knives and steels used that having all the techniques at your disposal can only help.
On another note you can cut a piece of paper with ease and still not cut a tomato
On another note you can cut a piece of paper with ease and still not cut a tomato
If you consider a 200 grit edge sufficient for kitchen work. Then cleanly cutting paper is a sufficient test of sharpness. (Sorry about the vacuum noise, if that wasn't there you could probably hear me remove the burr).
My typical progression for a knife in fairly poor condition is as follows. 60grit Sic, king 300, shapton 1000, then either I go on to a natural, or my king 4000, or kitayama 8000.
My goal with this progression is to repair damage with the 60 grit (which usually doesn't take long) It's so coarse I dont even feel a proper burr with it. Then I'm going on to my 300, then I keep going until I can't see any deep scratches on either side. I by then I usually have a decent sized burr. Then I do a couple stropping strokes to reduce it a bit. Moving on to the 1000 i repeat, just making sure all the scratches from the previous stone are gone, not so much worried about removing any burr at this point. After this I go onto my finishing stone. Whatever it is, I get rid of the previous grits scratches, then finally I start to really try to remove the burr doing as many strokes as I find necessary. After this I go on to a strop with either green compound, or .5 micron diamond emulsion to really be sure any burr is gone.
That's the thinking behind my whole progression. The whole process usually takes me about 5 to 10 minutes a knife.
Indeed! It's the old 'fine line between genius and insanity' thing. Obviously it's mostly just a matter of practice, and finding what you like but for me...
Do you go that high on knives you're sharpening professionally for other people, or is this for your own? When I'm sharpening for other 'non-knife-geek' people I'd rarely go past 1.2k...
Non-knife-geeks get Chosera 1K (after SG220 and/or Chosera 400 if needed for desperate cases) and stropped on denim.
My knives either finish on Chosera 3k or Debado 6K, depending on their own personal... idiom.
My knives either finish on Chosera 3k or Debado 6K, depending on their own personal... idiom.
Grayswandir
Senior Member
I would agree with just about everything said here, practice all the techniques you can and add them to your arsenal. There are so many different shapes and sizes of knives and steels used that having all the techniques at your disposal can only help.
On another note you can cut a piece of paper with ease and still not cut a tomato
I didn't realize that. My knives cut tomatoes with razor precision.
Grayswandir
Senior Member
No I don't, but that knife barely cuts paper. I think it's pretty evident that when a knife is sharp enough, it cuts through paper very cleanly. It's not a hill I'm trying to die on or anything, but if you inspected the edge of the paper that was cut in that video, you'd find a very jagged, ragged edge.
I apologize. That sounded more flippant than I meant. Paper cutting is fine as an evaluation tool. My point is just that it's a very low hurdle to jump.
Luftmensch
Senior Member
- Joined
- Dec 13, 2017
- Messages
- 2,316
- Reaction score
- 3,186
I did say:
I was attempting to raise a theoretical reason for why raising a burr once may be better than doing it multiple times (on each subsequent stone). I'll maintain that in a purely theoretical scenario, you only need to raise a burr once. After properly apexing a knife, there is no need to do it again. Instead, using your perfect robot arms, you can refine the scratch pattern on the bevel as you progress up the grits. While I dont see any theoretical need to form a burr on every stone, that does not mean there are no other advantages. Like you say, it may be a productive diagnostic tool.
My preference is to avoid burrs. But I'll issue a caveat. My experience is narrow. Unlike people who sharpen knives as a service, I only sharpen my knives. I have been using high-hardness carbons and wear-resistant steels for a long while now. It has been a decade since I used low-hardness stainless steel. I would likely be mediocre at sharpening these. So I am aware my observations are biased by this experience - I guess I should be transparent with anyone reading my posts.
Caveat aside, chasing a burr is not necessarily one of my objectives. I have not read into the material science of burrs but surely burrs are plastic deformation of the steel? If that is occuring you are creating fatigued steel right at the apex. If you have a big, flappy burr, you will have to tear it off somehow. An alternative approach is to keep the honing stresses low (below the yield point of the steel?). Ensure you are in a pressure regime where abrasion is the dominant force and not shear forces stretching/pulling the surface material. This will minimise the size of the burr. The trade-off is you spend more time on the stones (with less pressure). So far this is my experience with light edge leading strokes. Unless I am bevel setting to remove chips or other thinning events, I do not find burrs strictly necessary. If I had to choose a grit, it might say that I ignore burrs above 1K?
My control theory sucks... but it is mediocre enough to acknowledge the utility of closed loop control
.I'll freely admit that fairly early on, my finger sensing precision breaks down into: "better", "about the same" or "worse". At 4K and above... I might only be looking to see the blade feels uniformly sharp and that I haven't made it worse. Regrettably, this means I am operating on faith at higher grits - I dont have magic fingers that can tell the difference between an 8K and 20K edge. On the other hand... I find 4K to be a good practical limit for kitchen knives so I dont have a huge incentive to go any further
Luftmensch
Senior Member
- Joined
- Dec 13, 2017
- Messages
- 2,316
- Reaction score
- 3,186
Yes/No....
You are right. It is good at testing uniformity. You can detect burrs or dull spots. But I have to agree with @stringer:
Fortunately that might not matter. At that level of sharpness you are probably sharper than the overwhelming majority of kitchens. It is also a perfectly serviceable edge.
But you can do these tests in tandem... right?? Feel the edge with your fingers - then cut some paper. Correlate the results.... Do it for a dull edge. Do it for a screaming edge. Do it for an edge with a burr. Eventually you will have pretty good idea of how the feel of an edge will perform. At that point you don't really need to cut through paper. But that doesnt mean it stops being fun
