Well, it’s the latest thang, in the world of edge treatments, for long lived ultra-sharp. The latest thang in a long line of latest thangs perhaps. 🙂
Yet the experimentations offered to us on the web by the various advocates seem convincing ……….. Who here, I wonder, has tried this method of sharpening; and what have they found?
A short summary is:
Make a primary bevel (shallow but can be otherwise); then a slightly increased-angle secondary bevel; then a rounded edge with 5 seconds of buffing on a cotton wheel charged with buffing compound at about 45 degrees. The 5 seconds produces a teeny-weeny round-over at the very tip of the edge, which acts like a normal sharp edge but is far more resistant to wear or break-down, even in lesser steels on hard timbers.
The experimentation and evidence via subsequent microscopic pics of the edge seem convincing. Theories are offered about why such as edge holds up so much better, even in poor steels …. but these are still theories.
Here’s two links to descriptions of the technique and the experimental results.
http://www.woodcentral.com/cgi-bin/readarticle.pl?dir=newarticles&file=articles_958.shtml
https://chisel-test.netlify.app/
Lataxe
Replies
Here we go.
"The result is a chisel that holds an edge as well as or better than a chisel with a steep bevel, but also has the cutting ease of a chisel that has a shallow bevel, or at least near it. Perhaps more importantly, application of this method will allow underperforming chisels to work about as well as those of much higher quality".
If true, think of how this will please the many seekers after good tools here in the forum. We can tell them, "Buy a set for $25 from any old place then perform this magic spell upon them".
Mind, Lie-Nielsen and Veritas might go broke overnight!
Lataxe
This only works if a unicorn is spinning the buffing wheel on his horn.
By the law of transposed ends allied with the use of a Philosopher's Stone to transmute a unicorn into a porcine beast, a pigtail will serve as well with the buffer as the horn of the mythical demi-horse.
Despite being rather conservative (not that kind of "conservative") preferring the traditional to the new-fangle, I am not yet so ossified i' the head that I won't try a fangle or two, should they look promising. After all, I have two Festool Dominos, me! (As well as many of those queer old things called chisels and planes).
So I will attempt the unicorn with a cheap cotton buffing wheel and some left over honing paste from once owning a Tormek I sold as too fangly by half, not to mention hugely expensive. The subject will be a 1" cranked Narex chisel of the their bog-standard steel that I've just bought. Mind, ordinary sharpening procedures have it wicked-sharp already. .....
Lataxe
Never heard of it by that name, but I have tried using a buffer.... It worked as well as several other methods I've tried. I found it rounded ends of chisels too much for my taste, though.
I was a scary sharp kinda guy for about fifteen years or so... wet/dry paper on plates of some kind. Always dreaming of a worksharp, or diamond plates, etc.
But, I have recently become a convert to Rob Cosman's methods. I use a 300/100 Trend diamond stone, then I jump to a Shapton 16,000 glass backed stone. Also going primary, secondary, tertiary bevel route. It's what works best for me. But, that's just me and my work habits. Definitely not saying it's the best overall, or even a workable solution for anyone else.
Sharpening theory and practice - it could be a hobby all by itself!
I suppose many of us have been through the sharpening fashion cycle, although others have stuck with their oil stones on the grounds that "it works" - always a good argument really.
But, despite a great empathy for the oilstoners, I haven't been able to resist playing with the sharpening gubbins myself, as they hove into view in a forum, FWW article or even a Svengali advert.
Still, one does tend to gravitate eventually to a method that's as quick and effective as possible. Currently I try to buy already back-lapped sharp-edge things (or already reasonably flattish, at least) to avoid hours of back-flattening. I'll also use that Ruler Trick, given half a nudge, on many plane blades. Then comes the three bevel angles ...
These days I just leave the factory ground bevel as-is, even if it has roughish grinding scratches. I aim to make a secondary bevel just big enough the get the grinding scratches out near the edge; then a third micro bevel that gets the ultimate polishing. Diamond for the fast metal removal and 3M papers on glass for the few strokes making the final cutting bevel.
If a bevel needs a serious re-grinding, a Sorby Proedge belt grinder is switched on.
I strop the blades back to very sharp when they get a little harder to push through the workpiece. I have no real knowledge of why stropping brings back an edge three or four times before a re-doing of the teeny cutting bevel is needed, only guesses .... which I suspect may all be wrong.
The unicorn stuff with its microscope pics of edges like those I make vs edges made a la unicorn are therefore very interesting. The theory seems to be that machine-stropping the edge effectively gives it a much more even "line" (really a very small roundover) as well as a steep cutting angle of 45 - 50 degrees. The unicorner's guess is that this is what allows the edge to behave as a sharp edge but without so much readiness to break down via micro-fractures and bent-over thin edge metal.
One uniconer remark is that he wishes to dispute the notion that sharpness is the perfect meeting of two planes of different angles. That theoretically perfect edge is in practice too weak to last past one thrust o' the chisel or plane.
Fascinating! (Unless you have that very effective oilstone). :-)
Lataxe
As usual, Lataxe is right about the reasons for success. Also way funnier! Basically it lasts longer because it is a steeper bevel. It will not cut as well as a well-honed lower angle, but will cut a lot better than the poorly sharpened examples shown in the images.
Yeah, I don't know who sharpened those other blades. They did a really crappy job. Those aren't photos from an electron microscope. They are just poorly sharpened.
I build several major pieces of case furniture a year.
I heard about this technique in April and evaluated it by chopping a foot of practice dovetail with a Narex chisel. (not my normal chisel but I wanted to evaluate this profile on something I knew would otherwise fail) The Narex at 25 degree bevel will suffer some micro folding of the edge under these conditions. With the convex profile added to the last few thousandths of an inch there was no damage visible with a 10X lens.
Next up was a set of 4 drawers in ash for an ask desk. Again no visible damage at completion or drawers and tenons.
Currently doing a table with 4 drawers. Chopped something over 150 inches of dovetail and tenon waste and no damage with a chisel that by long experience would have suffered visible damage at this point.
I only keep one set of chisels in service. They pare and they chop. After the 150+ inches of chopping I am detecting some loss of paring sharpness. You will find after applying the Unicorn profile that the chisel will pare better, not worse as is claimed above.
If you build stuff with dovetails and mortises that needs chopping I encourage you to learn how to apply this profile (Article in Articles section of WoodCentral forum). Differing from the Article I add the profile after sharpening my usual way with a 25 degree primary bevel.
Well, for the folks above:
* no, the pictures aren't from an SEM, they're from a metallurgical scope. If you can't see edge problems under a metallurgical scope, for the purposes of woodworking they don't exist. For the purposes of straight razors, even, they don't exist.
* no, it's not the same thing as a flat steep bevel (a tiny flat steep bevel will work well, but not as well - if you want to eliminate chisel damage -an edge a couple of thousandths in chord at 34 degrees or more will mostly stop chipping. The buffed edge will get through wood far more easily and more cleanly in softwood). A larger flatter steep bevel is pointless (even a couple of hundredths) because it gives no greater durability and creates cut resistance. Oh, I guess you could say that cut resistance doesn't matter if you're not actually making anything.
* no, the edges aren't poorly sharpened, no two flat planes don't need to meet in a perfect point. The very point of two flat planes meeting on a "woodworking edge" exists for a very short period of time, perhaps 10 feet of planing. What can occur with it, though is that before it's removed, it can take damage and then that damage propagates further.
No, it is not the same as anything else, it is more similar to an enlarged version of what happens with a straight razor edge when the straight razor has seen linen and leather for a few cycles (at that point, a razor edge becomes strong). If a straight razor is shaved with straight off of a stone, the edge feels really sharp for a couple of passes, and then it begins to deflect (the same thing happens with commercial razor blades, which fail due to deflection and chipping, not due to wear).
As far as being substandard, here is a view of my bench through a shaving. The edge that created this (in cherry) was finished on a buffer with no finish stone and no further stropping.
https://i.imgur.com/nuk3Q0a.jpg
The idea is simple - remove the part of the edge that fails, or combination remove and modify. Make the part behind the edge (that never needed to be so steep) shallower after that's done, and then ditch the finish stone and the strop because no poster on this board has ever finished an edge with a strop and stone as well as a buffer can.
You can talk about what is or isn't, or you can do it and find out you're wrong.
There is nothing fiddly, cliquey, expensive or exclusive about the method. It's easier than most methods of sharpening, faster, and the edge lasts far longer. If you are afraid to try it but want to be an expert, that's just dumb. I was on this board for a short period of time a decade ago and it was saturated with people who pretended to be professional woodworkers or critics but who did their work during the day on a computer. The entire time I read, there was extreme hand wringing about suggestions to buy expensive tools or too-fine stone. This comes up as something that's almost free to do (literally a cotton buff, an arbor and compound -it can be done in a drill press for $15).
The response here is what I would've expected from years ago - I saw little of not being made then and most of the users criticizing people actually making things hid behind tage frid or someone else.
I wouldn't have been aware that there was even an active forum here if someone hadn't sent me an email. Someone who builds about a dozen 18th and 19th century pieces a year and who left this in their email:
" but I am up to
150+ inches of chopping in walnut to
make this table and drawers and no
detectable edge damage. It seems too
good to be true but the proof is a near
done table and the facts before my eyes"
The reference to the chair jockeys here was less flattering, so I left it out.
Nobody makes money off of this method, nobody is selling a video or a website, and it costs less than a single finish stone and makes the sharpening process agnostic about the hardness of the chisel or iron.
I can't tell anyone what to do, but when something works as well as this does, and people compare supposition of nots against actual proof otherwise....are you grasping what I'm saying there? In practice, this works one way. You suppose otherwise without any experience and feel like you're on equal footing - that's a very shaky footing to start from.
The other thing this does is protect the edge on really cheap chisels (just as it does all chisels), so edge holding and sharpness don't need to be gotten by spending a wad of money on chisels. Anything that's remotely close to usable hardness holds up, and nobody on this thread will have used a chisel that's effectively sharper for more than one hammer strike. And the edges shown here stay as their shown instead of being transient initial sharpness.
You think it's goofy because it costs almost nothing and it works? Don't suppose what you think is correct, actually do something and prove it wrong. Go ahead.
by the way, the "poorly sharpened" edges you're talking about are edges that have been used and have sustained damage.
They were sharpened to 1 micron diamond finish on the bevel side and an oilstone on the backside. The level of sharpness is better than anything you can attain with a typical 8000 grit waterstone, and they were done that way to avoid anyone claiming that initial sharpness was the issue.
They are magnified to 150x optical
This is an edge off of a shapton cream (12000 grit waterstone)
https://i.imgur.com/aEYDo5C.jpg
This is an edge off of the washita stone used for this test, and honed with a fine abrasive on the opposite side.
https://i.imgur.com/Ppn8wK4.jpg
Check the edge (not the lightness or darkness of scratches, but the evenness of the actual edge). If you think the shapton cream edge is a "poorly sharpened edge", you're in the weeds. 1 micron diamonds or buffer on one side and washita on the other is just a better edge.
Five birds custom, you were closer than you think. The trick to making this work is to start with a shallow angle and only allow a small strip of rounding. Too much and the chisel feels dull (and if used on a plane iron, the plane iron won't cut).
The notion about this kind of thing has always been either or. In this case, the edge is made by both. The initial setup is crisp, from a stone, but the fine work and modification of the tip is done (on purpose) by the buffer. Buffing isn't anything new, but guidance that goes with it has always been to avoid rounding the edge over. That's a theoretical wish from anyone recommending that, thinking that the edge starts as a crisp apex and stays that way, but the apex is gone beyond the level of rounding that we're doing in fewer than 100 feet of planing, and then there's damage to contend with.
You won't get an edge off of cosman's expensive suggested regimen that lasts with this, and if you want to buff plane irons with a finer abrasive, you won't get a sharper edge with cosman's regimen. Neither will he.
This method will be faster in general and lead to fewer edges where you haven't removed all of the nicks.
not sure if the other picture of the view through the shaving came through moderation, but his is the view through a cherry shaving. Through one, a continuous shaving, not through holes in a shaving.
The iron used to make this picture was done with this method and the actual iron was one of the really cheap buck brothers irons they used to sell at home depot for $2.99. They're so soft that they can be difficult to sharpen finely on stones, and the apex gets damaged easily if it's left in place.
buffing just the tip of the blade leaves this (focus less on the scratches on the bevel and the actual finish at the edge).
https://i.imgur.com/XmxkY1k.jpg
This is the scratch pattern and edge left by a shapton cream (which is only slightly coarser than a shapton 16k glasstone)
https://i.imgur.com/aEYDo5C.jpg
(I sell nothing, make no living teaching people with anything, and name nothing after myself - this whole method is just a matter of provable fact. you can go right from a 1k diamond hone to the buffer and get a similar result - it takes little time to perfect touch).
This is a picture of the back of an iron sharpened on 1 micron diamonds. I guess they're a lot more closely graded than the alumina in most waterstones as they don't leave much for visible scratches.
https://i.imgur.com/2lD38Td.jpg
Before sustaining damage, the chisels in this test were sharpened on the bevel side with the same diamonds used to make this picture. What's the virtue of the diamonds? They will create a finer edge on hardwood than the shapton 30k stone does, for about $10 for several years' worth. $25 for 100 carats (dry 1 micron diamond powder) would probably outlast a hobby woodworker's career, and they don't load or need flattening.
Lataxe - the chisels shown are through a little more than 1 cubic inch of maple, chopping. Not lightly and not overly heavy.
The deflection and damage occurs in that short span. You can keep using the chisel then (it's a lot more dull) or resharpen. When the damage gets to a couple of thousandths of an inch deep, you won't resharpen all of it out on just stones. Don't believe me? Buy a hand held scope and look at your edges after five minutes of use. It literally costs about $15 to find out what it is you don't know here.
Nothing more spent than $15 will really give you any greater information, just better pictures and a little bit easier to use.
You won't find your edges to be damage free or even lightly damaged if you sharpen less than 34 degrees, you'll spend about 10 times more time sharpening (a whole lot more effort using the chisels) and more money with your method, but you can assume you've won something. I don't know what it would be.
No chisel that I've ever seen (I've had hundreds) chops hardwood without damage. Almost all of them chop hardwood without damage when set up like this. Even the really cheap ones. The sorby chisels hold an edge less well than the chisels sellers popularized from aldi, and even they hold up almost perfectly - not quite. I've run into dozens of people who had them and sharpened on oilstones and waterstones and sold them because they couldn't get them to hold a usable edge.
The problem with 34 degrees plus is that it feels dull. If you aim to make a tiny bevel that doesn't feel so dull, then you need a honing guide (that's a waste of time).
The finest of oilstones (I have them all or have used all of them, from llyn idwall, to vintage trans arks to dan's black stone) is less fine than the buffer can make quickly. You can see it in pictures, and you can feel it. Someone with almost no sense and no touch can feel the difference.
About three times a week now, I get emails from people with excerpts like this:
"...do you think I could sell my 9 pc Fujihiro bench chisels in the forums and get a good price"?
This is from someone who unicorned a marples blue chip and trimmed plywood with it.
The apex of an edge is weak. People who set up slicing knives have known it for a long time. So have barbers. It only took me 15 years to realize you could intentionally do the same thing to woodworking tools.
It's not the same as sellers making a big fat round edge and wasting time honing parts of the tool, and it's not the same as pulling a chisel across a loaded strop unless you're willing to do the latter for a solid minute. The buffer lays about 90 feet per second on the edge of a chisel and leaves no evidence of a wire edge or anything of the sort, and the apex is gone if it's not babied. What's left lasts almost indefinitely on chisels.
Planes don't get as much impact damage unless wood is dirty or has silica, so there's less of an incentive to use the buffer on them. It can be used to create a better edge than you'll ever make by hand, cheaper and quicker, but it's not the absolute difference that exists on chisels.
Unicorn sharpening is a cruel practice and should be banned.
Ha ha - cruel to the oilstoners, who fidget and squirm as their hallowed practices are gradually made obsolescent and their ancient lore of little force compared to, at last, the new & improved modern modes of creating a long lasting super sharp edge on even a Bucky chisel!
It must be worse than being told that their 50 hours carving a ball & claw foot can be done on a CNC portable router in 8 minutes and 32 seconds. Yes.
Where will it all end? Perhaps there is a bloke experimenting with a magic putty that forms a perfect chisel handle shape for whoever grips it, returning to its neutral mode when put back in the rack to await a different user with a different shape of mit, even one with just two fingers and half a thumb (Unisaw users).
Lataxe
I'm not a carver or a furniture maker, I make some furniture, mostly tools, some guitars. I have yet to see much made entirely by CNC that looks like anyone with sense made it.
power carving to remove waste and then finishing carving by hand with minimal sanding is probably more typical. I don't think most of the people who buy ball and claw furniture are going to care for the taste of CNC users, and most will be educated enough to spot bad proportion.
Buffing is about as new as holtzappfel. As to how much better these edges hold up than two flat planes meeting, it must've been done a thousand times before and nobody thought it was worth sharing because buffing equipment wasn't that cheap, or more realistically, nobody has done much hand tool work for profit since before the industrial revolution.
What I am interested in is spending more time making guitars, tools, and occasional furniture and less time honing the damaged bits off of a chisel, or rehardening the odd set of marples gear that must've missed the splash on a high speed induction hardening line.
Two questions on the unicorn method.
Q1. Will it work on a chisel sharpened on a Tormek to 25 degrees ie, hollow ground, without any secondary bevel?
Q2. When presenting the chisel blade to the bottom of the buffer wheel, what is the angle of the blade to the horizontal, and is it above or below horizontal?
Let’s make that three questions.
Q3. If I have a hollow ground 25 degree chisel, surely all I have to do is hold the chisel at the buffing wheel so it fits in the centre of the hollowed bevel at a tangent, then simply lower the handle by 15 degrees so it is then buffing a 40 degree microbevel?
I had the joy of looking at a mate’s new Veritas A2 steel spokeshave blade, flat grind at 30 degrees, and could see the hairline thin 35 degree microbevel
I would also be interested in whether the Tormek's honing wheel can stand in for a buffer here.
“[Deleted]”
Greetings from the UK
Back in the early 1980s when I was demonstrating my Vascular biometric invention to the UK's NRDC ( National Research Development Corporation) See https://sites.google.com/site/veinpatternhome/home?authuser=1
I recall another inventor who was demonstrating a novel method of laying down diamond coatings on metal. The process involved loading diamond dust into a buffing wheel by incorporating it in a buffing compound applying it to the wheel and then buffing a diamond coating onto a steel implement... Interestingly it worked! No one knows why it works or what the physics is that produces this remarkable result. However, if you want diamond-coated wood chisels cutting edges do get some cheap industrial diamond dust and blend it with your polishing compound and get buffing.
Hope this tip helps do report your results.
Joe Rice
One can only hope that David Weaver notices this post then goes into his shed to perform Some Experiments With Diamond Dust, the results of which he will show here via pics from his microscope and some measured objective-data comparisons! How could he resist!!? :-)
Having now had unicorned chisel edges and a couple of unicorned block plane blades, for a good few months, I would opine that the edges are not only just as sharp as when sharpened conventionally but also seem to have a greater resilience than heretofore.
In particular, a Veritas A2 block plane blade used in a wooden plane I made myself has performed an enormous amount of work on a cherry item, filling a large waste bag with the shavings yet seeming to remain sharp for the whole process. That's a better performance than usual for any Veritas A2 blade of the many I have in various planes.
Of course, I haven't weighed the shavings, timed the planing done or made any objective measurements. But I do have a definitie impression of this unicorned plane blade being rather longer lasting i' the edge than is usual.
Lataxe
Yup, it works and is not new.
I was taught the trick in the early 80’s by famed carver WP Wilcox, who honed carving chisels on a leather disc made from glued up shoe leather bolted to a washing machine motor.
WP would touch up his tools at each break in seconds, (he used a 2 inch gouge for 90 percent of his carving) and would say, “We don’t get paid to sharpen tools, we get paid to cut wood.”
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