Bevel angle
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Jacob
What goes around comes around.
A sharpening thread! Is this a trap? 
The answer:
1 Don't grind them at all they were ground at 25º by the maker
2 Hone them very quickly at 30º.That's all you need to do - just a few quick dabs over a fine stone.
3 Ignore any advice you may get about flattening and polishing.
The answer:
1 Don't grind them at all they were ground at 25º by the maker
2 Hone them very quickly at 30º.That's all you need to do - just a few quick dabs over a fine stone.
3 Ignore any advice you may get about flattening and polishing.
Last edited:
Thanks Jacob
profchris
Established Member
I'd check that the back is flat (a few rubs across the sharpening stone will tell you), and if not I'd flatten the final half inch or so. If the back is concave or convex you'll find it hard to get a good edge across the full width.
Otherwise what Jacob said for everything except very fine, delicate work, where you might want to work more to get the best possible edge.
Otherwise what Jacob said for everything except very fine, delicate work, where you might want to work more to get the best possible edge.
The shallowest angle where the edge stops failing.
If they need a considerable angle, I would give them an angle shallower and then a tiny secondary angle. Like really tiny - for most reasonable angles, it's only the tip of the chisel that fails, so only the tip needs to be steepened. The more of the bevel you put at a fat angle, the more the chisel will resist a cut and wedge.
This is a good thing on a large mortise chisel, but in many other cases, it's not that great.
If they need a considerable angle, I would give them an angle shallower and then a tiny secondary angle. Like really tiny - for most reasonable angles, it's only the tip of the chisel that fails, so only the tip needs to be steepened. The more of the bevel you put at a fat angle, the more the chisel will resist a cut and wedge.
This is a good thing on a large mortise chisel, but in many other cases, it's not that great.
Jacob
What goes around comes around.
OP is presumably a beginner which is why I suggest just honing at the universal default angle of 30º.
He can always venture down the rabbit hole of modern sharpening later, if he really wants to, but best avoided IMHO!
He can always venture down the rabbit hole of modern sharpening later, if he really wants to, but best avoided IMHO!
I get more chisels from japan (that were used professionally and then cast aside for 50 years) sharpened my way than yours. There's nothing modern about it.
A very long very shallow bevel was also often used on english tools with a steep secondary or final bevel, presumably to speed sharpening. I've gotten in both on professionally used chisels (all deliberately sharpened the same) and planes that way.
The angle where a chisel stops failing is generally between 32 and 34 degrees. It's far smarter to sharpen a chisel at 25 degrees and then add a tiny stripe at one of those (and faster), but not much of the market of users is particularly smart. We're generally trying to do good clean work the easiest way possible.
Jacob
What goes around comes around.
Interesting. You advocate one thing. I advocate a minor variation that's far more effective, just as easy to do. My suggestion is "too complicated and a rabbit hole".
Proof always makes this less fun, I'm sure. This only needs to be worked through once - do it right the first time, especially on second tier chisels like these.
For the OP, this is an article I wrote last year. You can ignore all of the article for now, it's more of a thing for long-termers. BUT, look down the page until you see groups of pictures of edges. Note the difference for most (sorby chisels are soft, so not as well helped here by a small adjustment to angle) of these chisels between a 30 degree angle and 32.
Somewhere 32-34 is where chisels stop failing. The failure shown in these pictures is gained in minutes, sometimes almost immediatley. Eliminating it is in your interest.
The only way you won't see something like this is if you are work only softwoods that have no hard "stripes" (latewood) in them. Some fir and spruce has these latewood lines and still damages edges. All medium hardwoods and harder create this effect - these chisels were not abused - rather the way they were tested is a bit idealistic.
The 32 or a little more bevel can be very tiny on the 25, keep grinding the 25 back to keep the secondary bevel very small. The smaller it is, the easier the chisel goes through wood and the less crushing it does (if this isn't something you've seen yet, you will soon).
A 30 degree chisel bungled up like these pictures within minutes is far less sharp than a "oh, it's too blunt to add a couple more degrees" chisel. I counted strokes in this test - with improved edge retention came far fewer strikes hammering through a set amount of work.
http://woodcentral.com/cgi-bin/readarticle.pl?dir=newarticles&file=articles_958.shtml
At this point, the simple difference of adding a tiny steeper stripe instead of going all toward 30 degrees is what's of value. This is a very easy experiment to undertake.
All that said, if you have a chisel that continues to get edge damage much above 33 degrees, it's junk. The range for all chisels (from expensive japanese all the way to decent western) where failure stops is only a couple of degrees. like 2 degrees different between mediocre chisels and others.
Keeping the secondary bevel very small also makes it easier to nail dead on, and easier to remove/grind off if you don't. People who think they hone at 30 degrees as jacob advocates often don't come nearly as close as they think because they're honing all kinds of parts of the chisel that have nothing to do with cutting. I've received a lot of tools sharpened the way jacob advocates and they're never what people think they are.
Proof always makes this less fun, I'm sure. This only needs to be worked through once - do it right the first time, especially on second tier chisels like these.
For the OP, this is an article I wrote last year. You can ignore all of the article for now, it's more of a thing for long-termers. BUT, look down the page until you see groups of pictures of edges. Note the difference for most (sorby chisels are soft, so not as well helped here by a small adjustment to angle) of these chisels between a 30 degree angle and 32.
Somewhere 32-34 is where chisels stop failing. The failure shown in these pictures is gained in minutes, sometimes almost immediatley. Eliminating it is in your interest.
The only way you won't see something like this is if you are work only softwoods that have no hard "stripes" (latewood) in them. Some fir and spruce has these latewood lines and still damages edges. All medium hardwoods and harder create this effect - these chisels were not abused - rather the way they were tested is a bit idealistic.
The 32 or a little more bevel can be very tiny on the 25, keep grinding the 25 back to keep the secondary bevel very small. The smaller it is, the easier the chisel goes through wood and the less crushing it does (if this isn't something you've seen yet, you will soon).
A 30 degree chisel bungled up like these pictures within minutes is far less sharp than a "oh, it's too blunt to add a couple more degrees" chisel. I counted strokes in this test - with improved edge retention came far fewer strikes hammering through a set amount of work.
http://woodcentral.com/cgi-bin/readarticle.pl?dir=newarticles&file=articles_958.shtml
At this point, the simple difference of adding a tiny steeper stripe instead of going all toward 30 degrees is what's of value. This is a very easy experiment to undertake.
All that said, if you have a chisel that continues to get edge damage much above 33 degrees, it's junk. The range for all chisels (from expensive japanese all the way to decent western) where failure stops is only a couple of degrees. like 2 degrees different between mediocre chisels and others.
Keeping the secondary bevel very small also makes it easier to nail dead on, and easier to remove/grind off if you don't. People who think they hone at 30 degrees as jacob advocates often don't come nearly as close as they think because they're honing all kinds of parts of the chisel that have nothing to do with cutting. I've received a lot of tools sharpened the way jacob advocates and they're never what people think they are.
Jacob
What goes around comes around.
When the OP is almost certainly going to be using a guide, choosing one "that your master told you" to do and one that works, both being equally difficult. Ghee, wouldn't you choose the one that actually works better? I don't know. Part of the problem on these forums is that ideas that are provably less good are peddled as better "because I said so".
it's no different than cosman telling people that he really recommends they get a 30k stone. I've noticed that I can prove to people that it's not better, it costs more, and that for $10 I can find something even finer and faster in combination if someone really wants it - but they'll listen to cosman because...look, his signature is everywhere and he's a "coach".
it's no different than cosman telling people that he really recommends they get a 30k stone. I've noticed that I can prove to people that it's not better, it costs more, and that for $10 I can find something even finer and faster in combination if someone really wants it - but they'll listen to cosman because...look, his signature is everywhere and he's a "coach".
Yes I'm a relative beginner & yes they are ground to 25 degrees
AESamuel
Established Member
Noises from the rabbit hole!
They come close enough, within a degree or so.
PS and avoid starting off with a sharpening jig - they actually make it slower and more difficult. Nobody bothered with them at all until the modern sharpening boom kicked off.
I disagree. I am perfectly proficient at free-hand sharpening, having sharpened knives for many years. However, when I sharpen with a jig it is faster, more accurate and more reliable too. I say learn both and see which you prefer.
As to the OP's question. Usually chisels are ground at 25 degrees from the factory, and sharpened by the user at around 30 degrees. This isn't a fixed rule through, I sometimes sharpen at 25 degrees for a cleaner cut in joints or 35 for heavy use chisels, but 30 is a good general use angle.
Despite the bickering, you can really try anything - 30/32, whatever. But note that solving any issues with perceived difficulty through wood or fast edge damage is something you can do yourself rather than relying on rules of thumb. It usually results in less effort all around, and not more.
Quite often, we're told that comparing two chisels at a set angle shows one to be junk and the others to be great, but a degree or two may make the former just as good - you're just finding what works. If you're going to do more than just a little bit of work, you want to find what works well and makes work pleasing and not run around blind assuming observations match your expectations and never adjusting the latter when the former doesn't turn out as expected.
David C
In Memorium
Personally, I grind at 25 or sometimes 22 degrees.
Please be certain not to grind right to the edge, or bluing/overheating is likely. Leave a small sliver un ground.
I agree with D-W that honing at 32 to 35 degrees will give a longer lasting edge. This honing band is best kept very small, for rapid sharpening.
Simple honing guide like Eclipse 36 is very effective. (Beware, some of the clones are horrid, Faithful comes to mind).
Best wishes,
David Charlesworth
Please be certain not to grind right to the edge, or bluing/overheating is likely. Leave a small sliver un ground.
I agree with D-W that honing at 32 to 35 degrees will give a longer lasting edge. This honing band is best kept very small, for rapid sharpening.
Simple honing guide like Eclipse 36 is very effective. (Beware, some of the clones are horrid, Faithful comes to mind).
Best wishes,
David Charlesworth
Thanks to all for your input , it is a great help. Regards Tony
I have a Veritas guide that belonged to my father , would this do. Thanks Tony
Attachments
David - you know I learned to sharpen first in a vacuum from your DVDs. I learned a great deal from the method even though I've become lazy and impatient over the years - I still suggest it as a starting point for people to be able to have instant success of the "the smallest scratches all meet the edge on both sides" type.
My studies of edge failure following have been an attempt to continue further on my path to provable laziness, but they can become kind of intense.
The idea is still the same - the failure or success of sharpening is at the tip, and so is the failure or success of the edge in general.
That is a very good guide and will serve you well.
Jacob
What goes around comes around.
You will make up your own mind I'm sure!
I'd say don't give up on freehand honing too soon.
Once you've got it it's much quicker and easier. It's what sharpeners have done since the stone age, worldwide, without problem, without jigs.
If you are in the middle of a job you don't want to fhave to stop iddle about with jigs and angles. If necessary you can freshen an edge every few minutes - about as easy as sharpening a pencil.
The main thing about it is you can put lots of force and speed into it.
Paul Sellers demo is good
You can do the same with oil stones which makes it a lot cheaper (they last for life)
