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Philipp Jaindl
03-17-2018, 3:34 PM
So this is kinda a followup to my other Thread looking for a Finishing Stone, which ended up being a Imanishi 8000. Also as stated i've been doing this long enough to know that if you ask 5 people how they sharpen you get 10 answers.

Now coming from Diamondplates and being used to skew tools and pressure on the push stroke it doesnt work on the Stone, i did put 2 gouges in the stone fortunately they werent deep, though that made me realise rather quickly that i gotta change technique.

Basically what technique are you guys using on the Waterstones? especially for smaller, narrow tools.

Apart from the chance of gouging the stone i have trouble raising and getting rid of the burr on the waterstone then again its my first 8000 Grit stone, not certain if it should even raise a burr. Dont get me wrong the edges do get sharp but i can barely see and feel some remains of a burr in the light, dont know if thats normal from an 8000 Stone or not since its my first.

Any advise is appreciated

Regards Philipp

Chet R Parks
03-17-2018, 4:53 PM
I've always heard and practiced that if you don't have a burr your not at the edge. I'd be interested to hear of any other practice that contradicts this.

Tom M King
03-17-2018, 5:18 PM
Being self taught, I never bother to feel for a burr, but learned when a stone has done what it can by feel. I sharpen narrow tools on the sides of the stones so as not to worry about a large face getting a nick.

Patrick Chase
03-17-2018, 5:50 PM
I've always heard and practiced that if you don't have a burr your not at the edge. I'd be interested to hear of any other practice that contradicts this.

For a cutting stone, yes. For a finishing stone like Phillip's 8000#, it depends on the stone, the steel, and the technique. If it does draw a burr then it should be a microscopic one in any case. I can get a clean edge by lightly palm-stropping after a stone like that.

Note also that harder abrasives cut more cleanly and have less tendency to draw a burr (though at coarse grits *everything* does).

Chet R Parks
03-17-2018, 6:07 PM
Then I stand corrected. Thank you Patrick

Robert Hazelwood
03-17-2018, 7:26 PM
It could be a burr from one of your coarser stones that has not fallen off yet. I like to work the back of the tool on the finishing stone a little bit after working the bevel on each stone, to minimize the burr before I get to the final step. After working the bevel on the finishing stone I take some alternating passes, one bevel down, one with the back down, etc. If any burr remains at this point it is microscopic and not detectable by touch. Then I strop a bit on some bare leather, which should remove whatever remains. I test the edge with my finger callouses during the process and that will usually tell me if I need to do more work.

John C Cox
03-17-2018, 9:25 PM
I think as Patrick says - it depends a lot on the steel... This is a very common technique with conventional carbon knife steels... Most of the old classic knife steels ran 0.6% to 0.85% - and assuming good heat treatment - all the carbon is dissolved inside the steel... So moving the steel into a burr, then polishing and straightening the burr makes perfect sense. It's fast and very effective.

I get concerned when this same technique is used on modern high carbon carbide forming steels... Because these steels are made up of a matrix of carbon steel with really super hard carbide particles between the steel crystals... I worry about the carbides popping out of the matrix when "drawing a burr" and leaving you a very sharp, but very fast wearing edge..

I would not be surprised to find out that many of the old chisels we are familiar with were made of alloys and carbon contents that would be cooperative to this type of sharpening method... It was extremely commonly practiced after all...

Patrick Chase
03-17-2018, 10:08 PM
After working the bevel on the finishing stone I take some alternating passes, one bevel down, one with the back down, etc. If any burr remains at this point it is microscopic and not detectable by touch.

I can sometimes detect a burr at that stage by drawing my fingernail or fingertip very lightly along the edge. The burred parts will have slightly increased "drag" on my nail and will tend to bite at the skin of my fingertip
. You'll never detect it by trying to feel it directly, though.


I have a camera setup that can image down to ~2 microns, and at one point I went back and forth between taking shots of edges and feeling them. You really can detect remarkably small burrs by feel.

Derek Cohen
03-17-2018, 11:04 PM
You'll never detect it by trying to feel it directly, though.

You know Patrick, many say this. Yet I firmly believe that I can feel a 13000 wire. I must go and explore this more consciously to understand what it is. My thought is that either I can detect the fine wire with my finger pads, or it is the smoothness/roughness of the blade's edge that is creating this impression. Regardless, I can detect when it is present and diminishing in size. This observation is aided by looking for light reflecting off the edge.

Regards from Perth

Derek

Robert Hazelwood
03-17-2018, 11:27 PM
I can create and feel a wire edge off of any stone I have, even a Shapton 15k. Fingertips are pretty sensitive. But even when I have done everything I can to remove the burr and can no longer feel it, I still assume that there is always some tiny bit of deformed metal at the edge. I figure that is why the edge seems to get sharper after stropping on bare leather (no compound) even when I have been very careful to remove detectable burrs on the finishing stone. Of course who's to say the stropping isn't simply aligning the burr rather than removing it? I don't know, but at some point you have to say it's good enough and get to work.

I will try Patricks's trick of drawing a fingernail along the edge. I definitely think that managing the burr makes the difference between a good and great edge.

Patrick Chase
03-18-2018, 12:00 AM
One other remark, tangentially related to burring.

Sharpening stones can produce a fairly wide range of results depending on the amount of water and/or slurry present. In particular letting a water stone "run dry" at the end of honing makes it cut more finely and leave less of a burr in my experience. I do that almost all the time, and my comment about how I get a good edge from an 8K with hand-stopping assumes that sort of manipulation.

These sort of techniques aren't specific to Japanese-style waterstones, though each general type seems to require different variations.

Philipp Jaindl
03-18-2018, 10:06 AM
I've been running edges over my fingernail ever since i started sharpening and agreed you can absolutely feel if theres a burr or not and fingertips are very sensitive too, over time you know what a sharp edge should feel like. Thats how i know theres still an ever so slight burr remaining or not one where it should be.

In terms of Technique itself i assume its no pressure on the Push and pressure in the Pullstroke? or are you guys using only Pullstrokes to begin with? I know its different for everyone however im curious anyways, how far, if at all, are you guys Skewing Tools on the Stone?

Most of my Tools are regular Carbon Steels, O1 and the likes, not too fond of the High Alloyed Tool Steels like D2 or such. For HSS just the Diamondplates are good enough, dont have any tools that require a fine edge made out of it or Carbide.

Tom M King
03-18-2018, 10:21 AM
I sharpen everything on the push stroke. I think I was about 9 when my Dad showed me how to sharpen a pocket knife, when I wanted to whittle neckerchief slides for Cub Scouts, and that's the way I've done it ever since. The neckerchief slides are still here, and the Eagle does look a bit like a chicken, but I had never seen a real Eagle then.

Fancy steels have no love here either, but I rarely work extremely dense woods like Derek does.

Robert Hazelwood
03-18-2018, 11:21 AM
To continue on the burr theme, I used to be into knives and read a lot about sharpening. The knife sharpening gurus I liked to read thought that forming any burr during sharpening was a bad idea, because it would always leave some fatigued metal at the edge. To that end, one thing they would advocate is doing the initial shaping work on a "muddy" stone that produces lots of slurry, something like the classic King stones. The idea is that the slurry abrades away at the burr as it's forming. But when it's time to set the edge, the slurry would be a problem as it's always abrading away at the apex you're trying to perfect, so they recommend finishing on a harder stone that does not release many particles.

I don't think knife sharpening always translates in a practical way to woodworking tools- for example a muddy stone is a hassle if you are trying to maintain flat geometry. And since you are normally removing all of the wear and edge damage by working on one side only, it is pretty difficult not to form a burr during the early stages. But the general concepts are similar.

Philipp- when I am shaping the edge I go back and forth, generally putting more pressure on the forwards strokes. I think pulling strokes have more tendency to create a burr, or at least they make it more obvious, but I am probably going to be raising a burr regardless so I opt for speed. When the edge is shaped and polished, I finish it with alternating passes on the bevel and back, and these are all push strokes, very light, with the pressure biased to the very edge so as to cut away the burr.

Except for very narrow chisels, I usually sharpen between 45 degrees and 90 degrees (which would be side sharpening) to the direction of travel. This is just because it seems to make it easier to maintain control over the angle versus going straight on. For very narrow chisels it seems easier to control going dead on, so that's what I do.

Patrick Chase
03-18-2018, 9:13 PM
OK, I pulled my Imanishi/Kitayama 8K out this evening and honed a couple irons and a gouge on it (O1 and A2 FWIW).

As I remembered it has fairly average firmness for a polisher. It's harder than the Sigmas or Ohishis, softer than the Naniwa Snow White, but otherwise pretty typical for a magnesia stone (which is what it is). To initially establish the tip angle I must only use pull strokes. Once the tip's bevel angle is established (such that I'm honing a rectangle rather than a line) I can do light push strokes freehand, particularly if I skew the iron a fair bit so that the honing motion has a significant "side" component. With a guide you can do pretty aggressive push strokes on it with no skew, though again only after the tip angle has been established with pull strokes.

When you do gouge that stone it doesn't go terribly deep, so it isn't the end of the world. I wouldn't even bother to flatten them out - just pivot the iron a bit so that it won't "fall in" and keep working.

In terms of burr I can detect a small one when using the stone wet, though I can work much of it away by letting the stone dry out towards the end of honing (a very well known "stupid waterstone trick"). Palm stropping is sufficient to get a "woodworking clean" edge off that of stone, at least for me. I'd do more than that if I were going to shave with it, obviously.