Sharpening - dealing with the wire edge.

[John C Cox]

Hey guys.

I would appreciate some tips for dealing with the wire edge when sharpening.

I got a set of Aldi chisels.... So far so good - except they take a hideous and persistent wire edge when sharpening. That's aggravating - because the wire edge can peel off on the work - leaving a chipped chisel or a dull spot.... :( :(

Thanks

[Pete Taran]

Sounds like so far not so good. A wire edge when sharpening at coarse grits is normal, but should disappear when moving to finer grits. If you have edge failure while using your chisel, one of two things is happening. Either your sharpening angle is too small (like 20 degrees and using that chisel for mortising) or the steel is of dubious quality, or possibly both. I've been watching for the Aldi chisels at our local store, but they have never come in stock. Not that I need new chisels by any means, but just to check out the quality and test the hardness. They have not appeared here in NeOH. Sounds like they would make good chisels for beating in a tool box, but not cabinetry work.

[Jim Koepke]

It is often said once the back of a blade is flattened it will never need to be worked on again. Well, that is wrong. The back needs to be worked to get rid of the wire edge or the burr as some call it. There are many ways this is done. For me, it is done on the next stone. Some folks do not worry about it until the finishing or polishing stone. To me it seems better to get it off at each step.

My routine if the edge is rather worn is to start with a 1000 or 2000 grit stone then the wire edge is removed on a 4000 stone by pulling the back of of the blade on the stone. If the wire persists, then the bevel is pulled on the stone. This is repeated as needed alternating from back to bevel.

After the finishing stone, 8000 in my case, any burr or wire edge is worked on the 8000 stone or on a strop.

A few blades will hang on to the wire. In that case a few test cuts on a piece of scrap will usually take care of it.

This is pretty much the same if instead of water stones you are using oilstones.

My blades are made up of an eclectic accumulation from many makers. All the different steels do not act the same. A few of my blades seem like they could be stropped for an hour and there would still be those little pieces of metal trailing behind. It looks like small pieces of foil stuck to the edge.

jtk

[John C Cox]

Honestly - these Aldi chisels are performing better than my brand new Pfeil chisel - which cost 4.5x more for 1 chisel than the entire set of Aldi chisels. I am not happy with the Pfeil so far - as the edge keeps rolling on spruce!

[Rob Luter]

I work the back as Jim suggests above. As a final step I drag the edge through the end grain of a soft pine board. It strips any wire edge off. It's a tip I picked up in an issue of Fine Woodworking.

[Patrick Chase]

Sounds like so far not so good. A wire edge when sharpening at coarse grits is normal, but should disappear when moving to finer grits. If you have edge failure while using your chisel, one of two things is happening. Either your sharpening angle is too small (like 20 degrees and using that chisel for mortising) or the steel is of dubious quality, or possibly both. I've been watching for the Aldi chisels at our local store, but they have never come in stock. Not that I need new chisels by any means, but just to check out the quality and test the hardness. They have not appeared here in NeOH. Sounds like they would make good chisels for beating in a tool box, but not cabinetry work.

Another possibility is that he didn't spend enough time on his polisher (i.e. at the fine grits).

To the OP: Can you see or feel the wire edge in the sharpened chisel, or are you inferring its presence from the subsequent chipping?

If the former then you need to spend more time working the chisel on fine stones. If the latter then look to Pete's suggestions.

[Prashun Patel]

If you are getting a prominent wire edge at the higher grits (5000-8000) I am jealous. It's hard to see and feel at those grits. Achieving it means you are properly honing to the edge. Removing should almost always be easy by swiping the back on the highest grit once or twice, then inspecting the front and possibly going once on that side.

[John C Cox]

Sharpening setup:

worksharp electric unit. I am sharpening at 25-27 degrees of thereabouts... It is typically a bit higher angle than the original factory bevel grinds on my chisels.

Nearly everything I am doing is "paring".. Basically zero mortising. I haven't hit a chisel with a hammer or mallet in a couple years.

The wire develops visibly at the lower grits (220 and 400) when grinding out chips.
As I move up the grits - I can still see the wire edge, though it gets progressively finer.
When I rub the edge across my thumbnail after the micromesh grit - I can see the "edge" appearing to shift over.... This is the wire...

If I use the chisel at this point - it will roll the wire edge visibly...

Throughout the sharpening process - I give the back a go on my Extra-fine Diamond stone to ensure the burr doesn't roll over the back.

I am giving it a sideways run through soft wood (spruce or pine) and can see some of it come off... Not always all of it.

I typically then strop the bevel and touch up the back on my diamond stone... And repeat this as I work to keep it cutting well..

[Rob Luter]

Do you know the type of steel the chisels are made from? Years ago I had a coffin smoother with a homebrew iron I got at an antique store. It was over 1/4" thick. I took it to a toolmaker at work to have him grind a fresh primary bevel on it and flatten the back. He set it up on a die grinder and established a mirror flat back and perfect 30* bevel. No matter what, he could never seem to get rid of a feathery wire edge. I did some research on the steel and it turned out the chemistry wasn't very good for edge tools. It would harden OK, but the grain structure was too large as I recall. I would have to constantly hone it to get it to cut and always had to add a steeper microbevel to get rid of the wire edge.

[Kurt Cady]

I want to bet that you are using 200 and 400 grits way too often and getting a large thin feathery wire edge like you would get when re-shaping the bevel. I can visibly picture in my mind what you are seeing, something similar to what I saw with Narex chisels and a Worksharp (similar steel I believe) when I first started.

Here's an idea. Only use anything less than 1000 to reshape the bevel at 25deg. Then completely remove the wire edge with a high polish on the back. Next, sharpen at 1000 and up at 27 degrees. Do not move to the next grit until you can feel a wire edge with your fingers - it is very small, but can be felt. Hard for me to see without magnification. this will make your wire edge much smaller. Also, I don't know what grit your extra fine diamond is, but I doubt it is anywhere close to 8000 or the green compound - and I wouldn't use it to remove the wire and polish the back. It is also possible the chips you see are actually scratches on the back from the fine diamond stone.

I personally go many many many sharpenings until I go back to less than 1000.

Also, once you finish, you should essentially polish the back on a very high grit stone until the wire comes off completely. This is where the ruler trick comes in handy for plane blades - not chisels.

[John C Cox]

Re: crystal structure...

I was wondering about that...
Large crystal grain size can be caused by lack of normalizing or poor heat treatment even with "modern" alloys that are otherwise well behaved for this.

[Patrick Chase]

If you are getting a prominent wire edge at the higher grits (5000-8000) I am jealous. It's hard to see and feel at those grits. Achieving it means you are properly honing to the edge. Removing should almost always be easy by swiping the back on the highest grit once or twice, then inspecting the front and possibly going once on that side.

It's actually quite easy to get a prominent wire edge at the higher grits: Just don't work them enough to remove the one from the lower grits. Beginners do that all the time, and I suspect it may be happening here.

[Patrick Chase]

Do you know the type of steel the chisels are made from? Years ago I had a coffin smoother with a homebrew iron I got at an antique store. It was over 1/4" thick. I took it to a toolmaker at work to have him grind a fresh primary bevel on it and flatten the back. He set it up on a die grinder and established a mirror flat back and perfect 30* bevel. No matter what, he could never seem to get rid of a feathery wire edge. I did some research on the steel and it turned out the chemistry wasn't very good for edge tools. It would harden OK, but the grain structure was too large as I recall. I would have to constantly hone it to get it to cut and always had to add a steeper microbevel to get rid of the wire edge.

Oh, so you're saying your plane iron was made of A2? :-)

Sorry, I couldn't resist. Terms like "large ... grain structure" are of course relative.

IIRC Aldi advertises their steel as Cr-V, which can refer to an extremely wide range of alloys. Some of them take very refined edges, others are veritable chip-fests.

[Patrick Chase]

To the OP: I would lay off the extra-fine diamond plate. That's very coarse relative to any polishing stone, and may actually be drawing a burr. Just focus on using your polishing stones and untreated leather for now.

[lowell holmes]

Take a piece of wood and glue some rough raw hide to it. Then after sharpening your chisels, strop the edge on the rawhide.

I learned this from Paul Sellers at Homestead Heritage in Waco Texas 15 years ago. Try it, it works.

[Frederick Skelly]

I have been experimenting with my Aldi's at 22* for several months now, and use them for paring. So far, so good.

To remove the wire edge, I work the back as others suggest. Then I use a trick that I think I got from one of Charles Hayward's articles..... I make 1-2 passes down the length of the bevel, on the corner of a softwood block - like a knife slice, pendicular to the corner. It works for me, anyway.

Fred

[Rob Luter]

Oh, so you're saying your plane iron was made of A2? :-)

Sorry, I couldn't resist. Terms like "large ... grain structure" are of course relative.

IIRC Aldi advertises their steel as Cr-V, which can refer to an extremely wide range of alloys. Some of them take very refined edges, others are veritable chip-fests.

Nope. My A2 stuff sharpens great. This was some form of tool steel I wasn't familiar with (and I used to be a tool and die designer). As I recall it was group M Molybdenum high speed steel.

[ernest dubois]

I wouldn't rely on stroping to remove the burr, here is why. The pressure exerted against the flexible surface is going prematurely cause the burr to break off and leave a serrated edge. For an edge as smooth as possible the burr needs to release of its own accord by being honed off against a flat inflexible surface.375419375421375422 So, the quality of the sharpened edge is directly related to the grit of the last stone used to release the burr.

[Andrew Hughes]

You could try jointing the edge it will be stronger edge. Hold the chisel vertically on you finest grit stone and pop that wire off. If it's one long piece you will know that there's no defects in the edge.
You will need to go back to your finest stone in the same manner as before. The new wire should be very small and easily removed.

[Robert Hazelwood]

The advice so far seems good to me. I will add my own method: After I've finished polishing the bevel, on the finish stone I alternate back and bevel strokes, very light pressure with the bevel moving forwards. Perhaps 5-10 strokes; this seems to remove the burr effectively. The typical advice I've heard for woodworking tools is to remove the burr by just working the back on the finish stone. In my opinion that is not quite enough- it tends to just push the burr over to the bevel side. So you have to alternate working from each side, and with each iteration the burr gets smaller/weaker and is eventually gone. I follow up with a bare leather strop to remove any burr remnants....but the edge is almost always good right off of the finish stone. Alternating sides is easier to do while freehand sharpening, but can be awkward with jigs or machines.

I also agree with the other posters who did not like the idea of the diamond hone as a finishing stone for the back. I think you can still get a good enough edge with it (once you manage the burr issue) but they are very harsh for a finish stone in my opinion. If you don't have anything else to use (like a fine oilstone or waterstone, or something like a spyderco UF ceramic) then I would try very fine sandpaper or micromesh (on a flat surface)

[Derek Cohen]

Some steels, such as A2, are more reluctant to "let go" the wire. I think that it is important that one does not let the wire become large, as then it becomes more difficult to remove.

Years ago I would recommend removing the wire between stones, by flipping the blade and working the back as well. Today I feel for the wire and move on to the next stone as soon as it is present (I can feel a wire - or see it - at 13K). I suspect that some work the bevel with the lowest grit (e.g. 1000) more than they need to do, possibly to ensure that they have hones across the bevel face. A fine wire is enough - the bevel will not improve with a larger wire.

I expect that the wire to diminish in size as the stone becomes a progressively higher grit. By the highest grit the wire should be fragile and fall off. If it does not, then be prepared to work the wire back-and-forth on the highest grit until it has worn down and falls off. It must not be forced off (such as dragging the blade through end grain) as this will tear the wire and leave behind a serrated edge.

Regards from Perth

Derek

[Andrew Pitonyak]

Where do you live John? Perhaps you can duplicate the problem with someone from the creek present..... If you live in Ohio, you can swing by my place....

[John C Cox]

It would be a bit of a hike from South Carolina... ;).

I used to be a member in the Greenville Woodworker's Guild when I lived up that way.. Unfortunately they don't have anything like it down state.

The guys I have met down here hardly even use chisels and hand planes... If it can't be done with a table saw, drill press, or power nailer - they don't do it..

[Stanley Covington]

Pete has it right: Either the bevel angle is too low, or the steel has problems. Or... there might be other factors to consider.

I think many people do not understand just what a “wire” is.

Think about it. Draw yourself a cross sectional diagram of a chisel or plane blade with a "wire." Ask yourself “How does this thing develop?" "What happens when it breaks off?" Does it make my blade cut better?" "My job easier or more enjoyable?" Really think it through.

A “wire” is just a big honking burr: A long, thin flag of steel projecting from the cutting edge and curving out into space. They most often develop when the angle of the blade as it is sharpened on the stone is less than the angle of the blade's existing bevel. Draw these lines on your little diagram and you will see what I mean. Pressure of the blade on the stone causes the steel at the extreme cutting edge to thin, project outward, and bend, even if it is relatively thick.

Repeatedly bending this "wire" from one side of the blade to the other causes its root to work harden, become brittle, and break/ tear off. Work hardening results even if the steel does not heat up, you know. Imagine what the cutting edge looks like after this "wire" breaks off at its root. Not pretty. This damage can be fixed, but why waste the time, effort, steel, and sharpening stones? Best to avoid the whole bloody mess altogether.

When working a blade hard on rough stones to waste a lot of steel, such as when removing a chipped edge, creating a large burr is unavoidable, but it is pointless otherwise. Unless you are intentionally wasting a lot of steel, the burr that develops when using your roughest stone in the process should be invisible to the naked eye, and barely detectable when you drag your fingerprint ridges over it. This is the objective when using your first stone in a normal sharpening session. 1000 grit is where I start for normal sharpening.

Going back to the point I touched on above, it may also be helpful to consider why the bevel angle created during one sharpening session might become less than that made during a previous session, and how to avoid this tendency. Over repeated sharpening sessions, nearly everyone tends to gradually lay the blade down reducing the bevel angle. It simply feels more stable to do so. And at lower angles, the blade seems to cut even better,... until it fails, that is. Be sure to use a gauge of some sort to check your bevel angles when sharpening to confirm you are maintaining an adequate angle. When in doubt, 30 degrees is a good place to start.

Besides regularly checking your blade's bevel angles with a gauge, there are other things you can do to maintain the angle that works best for your tool and the wood you need to cut. First, pay attention and keep the blade’s entire bevel in contact with the stone when sharpening. It serves as a jig. This is more than a little difficult to do if your blades have double bevels or rounded bevels :).

Second, and most importantly, at the same time focus your efforts like a laser on keeping the blade’s extreme edge in contact with the stone. Use a marking pen to color the bevel so you can see where it is actually in contact with the stones. You may be surprised with what this reveals. Train your hand to sense when the extreme cutting edge is being abraded.

If you do this properly, a small, barely detectable burr (see "the objective" above) will develop on the rougher stones (e.g. 1000 grit), but will be cut down to nothing on the next stone without work hardening, breaking off, and creating a ragged, jagged edge that needs further repair.

Remember that your rougher stone must do more than just grind away damage at the cutting edge. It must also maintain the bevel angle that best suits the blade and the wood to be cut. In addition, it must also true and flatten the entire bevel, making the sharpening process quicker and surer. If you use your rough sharpening stones well, the rest of the process will be quicker and easier, and your blades will be sharper. I promise.

You can use a kanaban, or other lapping plate, with carborundum grit (or diamond paste, if you can afford it) to true and flatten the bevel. I was reminded of this technique last week by Mr. Nakano, a plane blacksmith, over crackers and tea in his living room. This is the surest and quickest way to achieve the ideal bevel. Hard to argue with 70 years of daily hands-on blade-making experience, and feedback from thousands of customers.

If you are doing all this right and your edge still develops a “wire,” it is very likely the blade’s steel is too soft at the cutting edge, and is being deflected and deformed into a “wire” instead of staying in place and being abraded away to nothing. Perhaps the blade was locally overheated on a grinder and lost its temper, or perhaps the manufacturer intentionally made it soft for his convenience. Maybe he just didn't pay attention. They look good on the website, after all. Such blades have their uses, I suppose, but do not make good woodworking tools IMO. Quality talks and posers walk.

[lowell holmes]

I say stropping cures a lot of ills when sharpening. Try it, if it does not work, do something else.

[Jim Koepke]

Even if my blade has a chip, the burr is worked off as soon as it is noticed. It may be a few removals of burr (wire) before the chip is gone. As Stanley mentions, a big burr is a big mess waiting to happen.

jtk

[Stewie Simpson]

Unless you are intentionally wasting a lot of steel, the burr you first develop on your roughest stone in the process should be invisible to the naked eye, and barely detectable when you drag your fingerprint ridges over it. 1000 grit is where I start for normal sharpening.

(politely) disagree with that comment.

[Derek Cohen]

Stewie, I think that Stanley is saying the same thing as I did, that is, there is no need to create a wire that is any larger than tiny - a larger wire is not a "better" wire. One can feel (with a finger tip) very tiny changes in a surface ... far smaller than one can see. I have no difficulty is detecting an 8000 grit wire with my fingers. If you can feel it, it is large enough.

Regards from Cape Town

Derek

[Stanley Covington]

Stewie, I think that Stanley is saying the same thing as I did, that is, there is no need to create a wire that is any larger than tiny - a larger wire is not a "better" wire. One can feel (with a finger tip) very tiny changes in a surface ... far smaller than one can see. I have no difficulty is detecting an 8000 grit wire with my fingers. If you can feel it, it is large enough.

Regards from Cape Town

Derek


Thanks for clarifying, Derek.

BTW, what are you doing in Cape Town? Can Perth survive your absence:)

[Derek Cohen]

Hi Stanley

Cape Town? My annual visit to parents, who live here ... well, my mum now. Dad passed away 3 years ago (nearly 101). I've been doing the trip from Oz for 35 years now. Post-Christmas is a quiet time in my practice as it is the long school vacation (I specialise in the child area), and so the best time to be away. We - Lynndy and I - usually use it as the first leg to "somewhere else". Last year it was the UK. This year? ... in a few more days we fly home ... and then I get a couple of weeks in the workshop!

Regards from Cape Town

Derek

[Stanley Covington]

Hope you have a great time in CT!

If your travels lead you to Tokyo, please let me know. I would love to meet you in person.

Regards,

Stan

[Derek Cohen]

Thanks Stan. Tokyo is definitely on the bucket list. And I hope you get to Perth one of these days.

Best regards

Derek

[ernest dubois]

Stanley, I think you are saying that at the moment the initial burr that develops at the lower grit stone is detectable it is time to move on to finer grit or even more ideally one would move up a grit just before, (inking the bevel as visual confirmation is better than the tactile confirmation the burr gives, if I understand you), there is a detectable burr and that a fully developed burr, one that is ready to release wouldn't even occur until the final strokes on the finest grit stone, and then come off with a stroke on the reverse side.
As I understand your posture toward the occurrence of a burr it has no utility in and of itself.

[Stanley Covington]

Stanley, I think you are saying that at the moment the initial burr that develops at the lower grit stone is detectable it is time to move on to finer grit or even more ideally one would move up a grit just before, (inking the bevel as visual confirmation is better than the tactile confirmation the burr gives, if I understand you), there is a detectable burr and that a fully developed burr, one that is ready to release wouldn't even occur until the final strokes on the finest grit stone, and then come off with a stroke on the reverse side.
As I understand your posture toward the occurrence of a burr it has no utility in and of itself.

Your summary of my position is partially correct. Allow me to restate.

First, manage the bevel angle, bevel flatness, and sharpening angle to ensure a big fat burr is not created, except when it is necessary to waste a lot of steel to remove chips or damage at the cutting edge. This assumes, of course, that the blade's steel is decent. The bevel angle gauge and ink on the bevel help with these tasks.

Second, the burr created on the first stone should be miniscule, evenly sized, and continue across the full length of the blade's width. Ideally, it will be difficult or even impossible to see with the naked eye, but detectable when you pass your fingerprints over it. If the blade is chipped or damaged, you will be able to feel discontinuities in the burr with your fingers and fingernail. When you reach this point, you can consider whether or not to move onto the next finer stone.

This burr should then disappear entirely on the next stone in the process leaving a clean, undamaged cutting edge. Physically breaking it off, or tearing it off in wood endgrain is counterproductive. Derek said the same thing, I believe. You don't want to work harden the burr, or leave a jagged edge behind, just abrade it smoothly away.

Before you move on to the finest stone in your series, there should be no detectable burr remaining. Fine stones excel at removing scratches and refining/smoothing the blade's surface, but are not effective at removing burrs.

Last week I visited with a professional sharpener in Nagaoka that specializes in sharpening blades newly forged by blacksmiths. We discussed this very subject. He uses carborundum stones followed by a lapping plate to develop the bevel, just like Nakano san. This creates a small burr, of course. He then uses a #1000 grit King stone, leaving NO burr behind. Of course, since these are new blades, he is working both bevel and flat on his stones. He then switches to a natural finishing stone. Not sure what the equivalent grit would be in synthetic stone terms. He produces a very good edge, with the beautiful appearance only natural waterstones can produce, on 40-50 plane blades a day. This jump to a natural stone straight from 1000 grit synthetic stone is a technique I have seen other top professionals in Japan use. Not just professional blade sharpeners either. I assume this is because they are able to do a superior job on the rougher stones than non-professional sharpeners. It is a a beautiful process to see.

I hope this makes sense.

Stan

[ernest dubois]

Thanks Stan for laying it out like that.
As I understand this is all, the thread, the bulk of the discussion ect... is going on and on in particular about plane irons with obvious application for chisels and maybe, theoretically, or under conditions of incredible discipline and control; edge geometry, steel characteristics at the moment of sharpening, condition of the sharpening surface ect... , each and every edge. In regards to planes and chisels I think this Japanese conception is obviously a practical one and have no reason to doubt it but for many other tools, gouges, gutter adzes, drawknives, axes and knives - what about your straight-edge razor? to name a few, just for the purpose of visualization, I find the burr - given that this implies a certain liberal attitude toward sacrificing steel - the most reliable - in that there is actual evidence - way to judge the moment of reaching the 0° defining actual sharpness, I mean, lets say as opposed to the fingernail test or intuition - not to discount that last at all, or at least in all cases - or something involving much more subjectivity. This is all just to say that, at least in my own case, the burr is not to be discounted. With the exception of when your steel is crap, and even then, you know at least there is no more need to waste your time on such an edge. As far as forcing the burr off whether jamming into ingrain - new to me - stropping the Doug Miller way - or who was it now? you will have an edge to work with for sure, it will just be a short-lived one, and I wouldn't want to shave my face with that edge.

[steven c newman]

And...you expect to learn all of that..from the "Normal" sharpening threads that haunt this site........:eek::confused::rolleyes:;)...Riiiight ...

[Stanley Covington]

Thanks Stan for laying it out like that.
As I understand this is all, the thread, the bulk of the discussion ect... is going on and on in particular about plane irons with obvious application for chisels and maybe, theoretically, or under conditions of incredible discipline and control; edge geometry, steel characteristics at the moment of sharpening, condition of the sharpening surface ect... , each and every edge. In regards to planes and chisels I think this Japanese conception is obviously a practical one and have no reason to doubt it but for many other tools, gouges, gutter adzes, drawknives, axes and knives - what about your straight-edge razor? to name a few, just for the purpose of visualization, I find the burr - given that this implies a certain liberal attitude toward sacrificing steel - the most reliable - in that there is actual evidence - way to judge the moment of reaching the 0° defining actual sharpness, I mean, lets say as opposed to the fingernail test or intuition - not to discount that last at all, or at least in all cases - or something involving much more subjectivity. This is all just to say that, at least in my own case, the burr is not to be discounted. With the exception of when your steel is crap, and even then, you know at least there is no more need to waste your time on such an edge. As far as forcing the burr off whether jamming into ingrain - new to me - stropping the Doug Miller way - or who was it now? you will have an edge to work with for sure, it will just be a short-lived one, and I wouldn't want to shave my face with that edge.

Ernest:

Most of the points you make escape me. Sorry.

If I understand it correctly, I respectfully disagree with your point (?) that "the burr... the most reliable - in that there is actual evidence - way to judge the moment of reaching the 0° defining actual sharpness..." If a burr exists at some point in time, the edge has not yet reached 0°. The thickness of the attached burr's root is the width of the actual cutting edge at that point in time, which is not zero. I think this is obvious.

Some like the idea that once the burr or "wire" is formed, continued sharpening will cause it to be severed cleanly from the edge in one piece. Perhaps this can happen, but what benefit does the extra length of a long "wire" provide compared to a miniscule burr? All I see is wasted time and the risk of a raggedy edge.

I am not saying to "discount" the burr. Please reread my posts carefully and confirm this. I am saying that only a miniscule burr is necessary, certainly not a "wire," and that a large "wire" is a result of careless sharpening technique. I am also asserting that there is no benefit to be gained by toying with the miniscule burr once it develops, but instead one should get right to work creating the 0° you mentioned. Indeed, if the blade geometry is properly maintained, it is my experience that the burr will disappear quickly leaving the desired 0° edge.

Does this address your points?

I am confused.

[Stanley Covington]

I use a straight razor custom made for me by Iwasaki from tamahagane. It seldom needs to be sharpened because I strop it on linen. No compound. When I do sharpen it, I use only a dedicated, fine grit, soft, natural stone.

I do not try to create a burr because I am experienced enough to discern the edge's progress.

Sharpening the razor does not consume much stone. But this is not a practical approach for planes and chisels and knives.

Unlike a straight razor, a plane blade, chisel blade, or knife blade almost always have some damage that must be removed. They are subjected to more abuse than a straight razor. Removing this damage requires wasting more metal.

A detectable burr is good way to confirm this damage has been eliminated. But the big loopy "wire" some feel to be a necessary step in sharpening is wasteful IMO. I don't know about you, but my blades are expensive, and my time is worth a lot, so I don't want to waste either.

With that thought, and vacation ending, this will be my last post for a few more weeks.

[lowell holmes]

My experience is that stropping on rawhide leather charged with green stropping compound works.
I learned this at a Paul Sellers class in Elm Mott Texas (Homestead Heritage) many years ago.
Like Paul, I keep a diamond hone out on the bench. When the edge needs touching up, two or three strokes
on the hone followed by stropping leaves a scary sharp edge.


DIFFERENT STROKES FOR DIFFERENT FOLKS.. :)

[ernest dubois]

Ernest:

Most of the points you make escape me. Sorry.

If I understand it correctly, I respectfully disagree with your point (?) that "the burr... the most reliable - in that there is actual evidence - way to judge the moment of reaching the 0° defining actual sharpness..." If a burr exists at some point in time, the edge has not yet reached 0°. The thickness of the attached burr's root is the width of the actual cutting edge at that point in time, which is not zero. I think this is obvious.

Some like the idea that once the burr or "wire" is formed, continued sharpening will cause it to be severed cleanly from the edge in one piece. Perhaps this can happen, but what benefit does the extra length of a long "wire" provide compared to a miniscule burr? All I see is wasted time and the risk of a raggedy edge.

I am not saying to "discount" the burr. Please reread my posts carefully and confirm this. I am saying that only a miniscule burr is necessary, certainly not a "wire," and that a large "wire" is a result of careless sharpening technique. I am also asserting that there is no benefit to be gained by toying with the miniscule burr once it develops, but instead one should get right to work creating the 0° you mentioned. Indeed, if the blade geometry is properly maintained, it is my experience that the burr will disappear quickly leaving the desired 0° edge.

Does this address your points?

I am confused.
Ernest:

Most of the points you make escape me. Sorry.

If I understand it correctly, I respectfully disagree with your point (?) that "the burr... the most reliable - in that there is actual evidence - way to judge the moment of reaching the 0° defining actual sharpness..." If a burr exists at some point in time, the edge has not yet reached 0°. The thickness of the attached burr's root is the width of the actual cutting edge at that point in time, which is not zero. I think this is obvious.

Some like the idea that once the burr or "wire" is formed, continued sharpening will cause it to be severed cleanly from the edge in one piece. Perhaps this can happen, but what benefit does the extra length of a long "wire" provide compared to a miniscule burr? All I see is wasted time and the risk of a raggedy edge.

I am not saying to "discount" the burr. Please reread my posts carefully and confirm this. I am saying that only a miniscule burr is necessary, certainly not a "wire," and that a large "wire" is a result of careless sharpening technique. I am also asserting that there is no benefit to be gained by toying with the miniscule burr once it develops, but instead one should get right to work creating the 0° you mentioned. Indeed, if the blade geometry is properly maintained, it is my experience that the burr will disappear quickly leaving the desired 0° edge.

Does this address your points?


I am confused.
I don't want to ruffle feathers so please forgive me.
Ok, we stick strictly to the plane and chisel family.
At the point when the burr releases of its own accord, the angle at the edge is then close to the theoretical 0°. That was my meaning. It was a blunder not saying it outright just then.
No disagreement as far as I can tell on, the smaller the burr the better, or let me put it another way, the more ideal. Raise the burr and get on with it, I also say. What is important is the existence of the burr along the entire length of the blade, the more consistent the better. But you know, and I must confess, sometimes I get the beginnings of a burr here and not there and before I do get the burr there, who knows, maybe I have let a hollow in the stone develop, or something, un-centralized downward pressure on the blade, I don't know, but it happens, call it sloppiness then if you want but that burr is more developed at the edges than through the middle. Yes, I will address the cause of the problem - this time or the next time - but it does happen, bla bla bla, ok I go on and on...

But I did go back quickly through your posting ups Stan and I'm sorry when I missed it or am to dim to catch on but in your process I don't see how you are using the burr other than maybe as a gauge of consistency or whether the geometry of the bevel and flatness of the stone are in sync.

I too rarely sharpen my straight-edge, stropping all the time you know. But it has been 10 years or more since I took my razor strop from the bathroom and hung it at my sharpening station in the workshop, and that a razor of any kind has crossed my rosy cheek.375732

[Stewie Simpson]

To add further to the confusion Stanley iterations on working the full bevel, and avoiding 2 bevel angles, refers to the Japanese practice of a single flat bevel to protect the softer laminate steel relevant to Japanese chisels and plane irons. It has little to no relevance to the common practice in western world countries of a hollow ground primary, followed by a steeper secondary bevel.

[lowell holmes]

I never had issues with the burr breaking off. My edges are razor sharp.
Barbers have stropped razors for centuries. I consider it to be a proven practice.
I don't sharpen my plane irons and chisels thin. I think my bevel is probably close to 30 degrees.
I will measure them tomorrow.

Don't over think this issue of sharpening. If you had 15 woodworker in a class, there would probably be 15 different
ways of sharpening.

[Patrick Chase]

Don't over think this issue of sharpening. If you had 15 woodworker in a class, there would probably be 15 different
ways of sharpening.

More ways than that, I think :-).

[Robert Hazelwood]

I agree with the idea that ideal sharpening would create no burr at all, and that if any burr must be created the smaller the better. I sharpen knives like this. But with woodworking tools with a bevel on one side only, this is not so feasible. This is especially true for plane irons- if the iron has any significant amount of wear (a visible wear bevel on the back) it is always the case that I will form a burr before the wear is completely removed. By the time the wear is gone, the wire edge may be fairly large, depending on how worn the iron was. I will usually work the back a little on the finish stone before continuing bevel work on the next stone, which minimizes the burr.

[Stewie Simpson]

Well stated Robert. The size of the wire edge being worked from your roughest stone is of little consequence. What's of primary consideration is removal of the wear line, and the re-establishment of the steeper secondary bevel. The initial wire edge will diminish in size as you proceed further through your finer grit stones.

[Jim Koepke]

Don't over think this issue of sharpening. If you had 15 woodworker in a class, there would probably be 15 different
ways of sharpening.

And many of them would have alternate methods they use at times.

jtk

[david charlesworth]

My habit is to get a small wire edge on an 800g stone at say 30 or 33 degrees.

Then make about 4 gentle polishing strokes on a 10,000g stone having raised the angle by about 2 degrees. This just means shortening Eclipse projection by a 2-3mm.

If it is a plane blade, I use ruler trick on back maybe 20 very short strokes (10,000 stone). Chisels of course are kept completely flat. There is a short clip of this on my You Tube channel)

If I see any trace of a wire edge after wiping and drying, something has gone wrong!! (And I might repeat). But this happens very rarely.

Persistent wire edges are a throwback to the bad old days of "coarse and fine oilstones).

Best wishes,

David

[Patrick Chase]

Persistent wire edges are a throwback to the bad old days of "coarse and fine oilstones).

Them's fightin' words in some circles.

Seriously though, you raise an important point: Sharper and cleaner-cutting abrasives generally deform the steel less than ones with more rounded grains (or than softer abrasives with more tendency to go blunt), and leave smaller burrs or wire edges when all else is equal. In my experience alumina as in your waterstones leaves less of a burr than Silica on most steels, and diamond leaves the least of all. This is not to say that one is "better" than the other - sharper-cutting abrasives come with downsides as well (specifically, deeper/sharper scratches which may or may not impact edge life depending on the steel and who you ask).

The steel also matters though, with tougher/softer steels being more prone to deformation and burr formation than harder and more brittle ones. I like my various Narex chisels quite a bit, but that austempered Bainitic steel is tougher and chewier than most martensitic tool steels, and it's definitely more burr-prone. Of course that same toughness also makes it very tolerant of heavy [ab]use.

[steven c newman]

Same here..IF I do see a wire edge flaking away....means I have to keep going, as the edge is now duller than when I started....sometimes a small burr will show up. Used to see them wire edges....not much anymore.

[lowell holmes]

I keep a diamond hone out on the bench along with rawhide on a wood strip of wood. The rawhide is charged with green sharpening compound.
The hone leaves a slight burr which the raw hide strop removes.
I learned to do this from Paul Sellers at Homestead Heritage in Waco Texas.
My edges are razor sharp.

[Warren Mickley]

. Persistent wire edges are a throwback to the bad old days of "coarse and fine oilstones). Best wishes, David
When I read stuff like this it makes me think the writer has little feel for how an oil stone works.

[Patrick Chase]

When I read stuff like this it makes me think the writer has little feel for how an oil stone works.

Can we all just agree that an experienced WWer can get terrific results from any of the aforementioned abrasives and move along?

I don't think it should be a controversial observation that sharper-cutting abrasives cause less plastic deformation than "rounder" ones. Like everything in life it's a tradeoff with both good (potentially cleaner edge off the stone) and bad (sharper/deeper scratches) consequences. It should be no surprise that the very same property that makes natural oilstones "gentler" also causes them to deform the metal more.

IMO reasonable people can disagree as to which is "best".

[Stewie Simpson]

It should be no surprise that the very same property that makes natural oilstones "gentler" also causes them to deform the metal more.

I will leave that comment for Warren to answer.

[Warren Mickley]

<p>

. IMO reasonable people can disagree as to which is &quot;best&quot;. I would like to point out that I did not disparage anybody else&#39;s method, but someon did disparage my method. I can&#39;t believe this escaped your notice.&nbsp;</p>

[Prashun Patel]

Everyone:

Let's not further the disparagement debate.

We should all be able to endure criticism of the content of our posts. But be careful that it isn't a veiled attack on a person's ability or knowledge. There are ways to object amicably. You know it when you write it, and we all know it when we read it. So please abide.