Bevel angle on double bevel chisel

[Sean Hellman]

Come on Jacob we are taking about straight chisels and skews, not gouges or single bevel general wood chisels. For these skew and straight chisels for letter carving, what I say stands. When having to cut or incise an accurate line at a set and consistent angle a flat bevel really helps, of course you could do it with a convex bevel but why? I agree that other chisels can and are often convexed, not too much of and issue expect to say for the beginner that they can often get really big bevel angles especially near the edge.
Again if not experienced with stropping on wheels it is very easy to round over the edge and corners, it is fair and right to warn people about this as if you get it wrong it can be a lot of work to correct.

I have taught hundreds of people over the years and see what happens when the inexperience sharpen and I like to give people ways of sharpening that help avoids issues. Of course there are lots of way to achieve sharpness and my opinion is based on 25 years of teaching and personal practise. It takes time to learn accurate freehand sharpening and even if you dip you still have to place or lift back up to the sharpening angle and this can be a bit hit and miss at first. Far better to set the sharpening angle as I describe and then convex the rest of the bevel that way if you over lift hopefully you do not change the included bevel angle.
We have an issue here because if we talked and showed each other face to face we would probably agree on most sharpening practises, or would we stab each other with our freshly sharpened tools : )

 

[D_W]

Come on Jacob we are taking about straight chisels and skews, not gouges or single bevel general wood chisels. For these skew and straight chisels for letter carving, what I say stands. When having to cut or incise an accurate line at a set and consistent angle a flat bevel really helps, of course you could do it with a convex bevel but why? I agree that other chisels can and are often convexed, not too much of and issue expect to say for the beginner that they can often get really big bevel angles especially near the edge.
Again if not experienced with stropping on wheels it is very easy to round over the edge and corners, it is fair and right to warn people about this as if you get it wrong it can be a lot of work to correct.

I have taught hundreds of people over the years and see what happens when the inexperience sharpen and I like to give people ways of sharpening that help avoids issues. Of course there are lots of way to achieve sharpness and my opinion is based on 25 years of teaching and personal practise. It takes time to learn accurate freehand sharpening and even if you dip you still have to place or lift back up to the sharpening angle and this can be a bit hit and miss at first. Far better to set the sharpening angle as I describe and then convex the rest of the bevel that way if you over lift hopefully you do not change the included bevel angle.
We have an issue here because if we talked and showed each other face to face we would probably agree on most sharpening practises, or would we stab each other with our freshly sharpened tools : )

Warren Mickley is a somewhat well known professional here who does a lot of carving. He is pretty militant (my words) about working with flat bevels, including on chisels. I'm fairly sure that he does a whole lot of non-carving work with the bevel into the work rather than facing away from it, too, which isn't bad policy as the edge seems to fare better that way.

Well, Warren is well known because he can be a little hard on people making inaccurate statements, but he doesn't show his work much. Some of his carving is on Anderson and Stauffer's page as contributions to pieces there.

By flat bevels, I mean that the edge is relatively little relieved from the actual angle ridden, it's all one. I'm aware other people do it differently, but much of the bad advice on here and other places relates to willy nilly bits about grinding or referring to people like paul sellers who are just trying to get anything half workable to beginners (and my opinion, operate something akin to pro wrestling kayfabe when it comes to anything else above the level of that). Poor grinding and "anything goes" there is a recipe for failure sharpening or using tools.

I'm more of a toolmaker than a woodworker, but I do often get tools to refit from people, and lack of clearance from chasing over a rounded edge is extremely common. The intent is to avoid using a grinder, but it almost always ends the same way as amateurs try to follow people like sellers and they're not familiar with something like a crystolon stone if they want to grind by hand, and how it's a huge part of the process, like all work. The set up for the finish is the key, and the finish is a brief few blinks if everything else was done right.

 

[thetyreman]

I prefer freehand sharpening with gouges but don't claim to be even close to an expert carver, I just use my one gouge to remove huge chunks of wood or whenever I need to hollow out a flat surface.

 

[Jacob]

Nice letter carving demo here. Very low keyed approach.
https://www.finewoodworking.com/2006/10/15/letter-carving-basics

 

[Jacob]

.....It takes time to learn accurate freehand sharpening and even if you dip you still have to place or lift back up to the sharpening angle and this can be a bit hit and miss at first. ...

Yes hit and miss for a beginner for half an hour or so but it doesn't take long to hit 30º fairly consistently. You place the chisel on the stone at 30º and push it forwards, dipping very slightly as you go and with as much force and speed as you can muster. Then repeat.
Sharpening is much easier than the "experts" would have you believe. Actually it took me some time to work this out for myself, having got diverted into the crazy world of modern sharpening with jigs etc etc. It was quite a sudden realisation and a great relief!

 

[Argus]

Free-hand carving is one area where jigs don't come into it....... theoretically, it's possible to lash a (Sheffield List) No: 1 straight chisel into a jig, but try doing that with a gouge, or better still, a Vee tool!

In carving, a bevel with a defined 'heel' at the back of a gouge or straight chisel is the last thing you need - it will mark the work and likely cause splits, so a curved heel is part of the geometry where it differs from what is thought necessary in conventional chisels coming straight from a sharpening system...... some of us even round over the 'ears' at the edges of the bevels for the same reason, but that's a personal choice........

Anyway, the OP mentioned an obscure section of the carving spectrum when he said that he is cutting incised letters - presumably a sign.

If a No: 1 straight chisel is used for this, a 30 degree total bevel angle is a bit generous for lettering; it's fine for rough-hewing larger pieces to a shape with a mallet where a strong edge is the first essential, but paring back the straight sections of a typical 'Roman' font needs a much lighter touch and a sharp, sharp tool.

 

[mudman]

Flat bevels not essential. Two bevels not essential. Just myths of the modern sharpening fraternity. Difficult to achieve anyway if not using a machine or a guide. Slightly rounded bevels is the norm with trad sharpening. Not deliberately, it's just easier to relax a bit!
Rounded bevels can be essential for carving - it's obvious really, a lot of carving involves a scoop action especially gouges which go in and come out of a smooth cut

Not if you are careful. I strop on face of an MDF disc + autosol, on outboard end of lathe. Very fast almost instant polish.

Rocking is perfectly OK as long as you dip rather than lift, so that the edge doesn't get dubbed over 30º, or your chosen angle. in fact it's a very efficient way of hand sharpening - you start at 30º and dip the handle as you go, which means you can put a more force into and make it faster, but still control the edge angle.

There's a lot of different opinions about sharpening!

By damn you do talk some dung.
Rounded bevels may be fine for generic bench tools but for carving gouges you need a flat bevel. No point telling you why.
You seem to have some obsession with promulgating rounded bevels everywhere but refuse to consider that there may be occasions where they are to be avoided. I remember a time, a fair few years ago that you tried to promote the rounded bevel for woodturning, a positively dangerous thing.
So FFS, give it a rest, do your evangelical rounded bevel thing with planes and bench chisels, I even did it on my OBM chisels l. But when it comes to more specialised areas that are outside of your area of expertise, I think you need to think a bit more before offering advice that you really aren't qualified to give.

 

[Jacob]

By damn you do talk some dung.
Rounded bevels may be fine for generic bench tools but for carving gouges you need a flat bevel. No point telling you why.
You seem to have some obsession with promulgating rounded bevels everywhere but refuse to consider that there may be occasions where they are to be avoided. I remember a time, a fair few years ago that you tried to promote the rounded bevel for woodturning, a positively dangerous thing.
So FFS, give it a rest, do your evangelical rounded bevel thing with planes and bench chisels, I even did it on my OBM chisels l. But when it comes to more specialised areas that are outside of your area of expertise, I think you need to think a bit more before offering advice that you really aren't qualified to give.

I'm not into "promoting" rounded bevels I'm just pointing out that a slight convexity is nothing to worry about. If you do a casual but speedy freehand sharpening that's what you'll get anyway, difficult to avoid, but there's no need to struggle for perfect flatness. This applies to turning chisels too, though I do mine on a flat sanding disc - they'll never be concave at least.
No doubt there are special circs where perfect flatness helps, but these are rare.
It's become an obsession with modern sharpeners but hardly gets a mention in the older books. I think it's a by product of the use of jigs, where flatness is inevitable and even stones have to be perfectly flat to work at all. Jigs were almost unknown not that long ago.
Looking at our letter carving expert above he seems to use a normalish bevel edge chisel (though he's wrapped it up for holding) with a normal looking bevel which looks to me to be slightly convex. For flatness he's using it flat face down, which makes sense.

 

[Jacob]

.....so a curved heel is part of the geometry

"...a curved heel.." amounts to the same thing as slightly convex.

where it differs from what is thought necessary in conventional chisels coming straight from a sharpening system...... ....

Not thought necessary in the past and still isn't necessary.

PS I'm not "promoting" a convex bevel as something to be aimed for deliberately, it's just an incidental, but there are some occasions when it is really useful.
Chris Pye shows this on p27 of "Woodcarving Course...." where a flat bevel chisel wouldn't do the job.
On the page 26 opposite he also recommends "slightly rounded" and "rounded" bevels for all gouges.
On page 24 he recommends "flat" to "slightly rounded" to "softened heel". Softened heel seems to mean effectively the same as slightly rounded.
In older books the word "flat" hardly gets a mention!

 

[AJB Temple]

This thread seems to be introducing some confusion about bevels. What Chris Pye means by double bevel is a chisel that is beveled on both sides - like a western knife. He promotes the auriou chisels that are sold by Classic Hand Tools and I expect this is what the OP has got.

A conventional chisel of course has a flat back and a single bevel - confusion is added when people out a micro bevel on the cutting edge and then describe it as double bevel.
The excellent video that Jacob linked to, mostly shows letter carving with a conventional flat backed single bevel chisel. Personally I prefer this for letter carving (having tried both) but one can adapt to either with practise. There is no doubt that having a very sharp, stropped edge makes carving cleanly a great deal easier.