Bevel edge chisel question

[Dan S]

I was working on some new bevel edge chisels tonight, and started thinking about the side bevels. How come the side bevels are so steep? I know a lot of people say it's so you can work on dovetails, but it seems like the bevel angles would only need to be 10 to 15 degrees for this, not the 45+ that most chisels seem to be.

What's the deal?

[Vic]

Dan, I would assume for the strength of the chisel. If they were less the taper would have to start further in and they wouldn't have as much resiliency. But, as my wife says about many things I say. This may have ass matter on it. )

[Ben H]

I'd say Vic has a very valid point. It could also be less material is less cost = more profit.

[Jonathryn]

I was working on some new bevel edge chisels tonight, and started thinking about the side bevels. How come the side bevels are so steep? I know a lot of people say it's so you can work on dovetails, but it seems like the bevel angles would only need to be 10 to 15 degrees for this, not the 45+ that most chisels seem to be.

What's the deal?

Can you post pictures? Most readily-available chisels are called "bevel edged," but the bevels are negligible, really more like decoration on what are for the most part really firmer chisels, (i.e., chisels with a rectangular cross-section). For real, honest-to-goodness bevel edges you have to go to Ashley Iles, Lie-Nielsen, and Blue Spruce chisels. On those chisels the bevel comes right down to the chisel back, where there's a bit of a "land" so there isn't a knife edge where the sides meet the back, but the bevel is pronounced enough to get into the corners on dovetails.

Some people argue that you don't need that pronounced bevel edge to make dovetails, because dovetail chisels didn't exist back in the day. But if you sharpen old timer chisels by hollow grinding with a wheel, it mitigates that shoulder, and a lot of the older, longer paring chisels I see have fairly small lands.

Western chisels are made by heating up high-carbon drill rod, then die stamping it into rough shape. After hardening and tempering, they're ground on the top and bottom and sides and cutting bevel, so removing metal actually costs time and abrasive material (read: $), rather than adds, to the bottom line. That's why a Lie-Nielsen chisel costs $55--the back is flat, it's honed to razor sharpness, it's mechanically correct, and ready to go. With less expensive chisels, the expectation is for *you* to do that work.

[Dan S]

Here is a quick sketchup drawing.

the cross section on the left is what I'm use to seeing, a flat bottom a land on the sides (height varies by manufacture), and then a sever bevel on the top of the sides (like maybe 45+ degrees from vertical).

The cross section on the right is how i would do it, a flat bottom, and then sides that are beveled just enough (15 -20 degrees from vertical) to clear common dovetail angles.

The cross section on the right would be stiffer, and potentially easier to machine depending on the process. It would probably also be easier on your hands as well (no super acute bottom edge).

[Jonathryn]

Hmm. Good question. On the smaller chisels (1/8, 3/16, 1/4), the two types start to resemble each other anyhow. But when you're trying to get right down into the corner of a dovetail, you want something of a knife edge rather than a square edge, because you kind of wiggle it down into that corner. It's better demonstrated than described. You're not holding the chisel perfectly vertical; the handle sways a bit to the right and left. Another aspect of it I suppose is how you do your dovetails--do you cut the areas between the pins with a coping saw and *pare* with a chisel, or do you skip the coping saw and *chop* them out? My dovetail journey started with some Stanley banger chisels, but the square sides bruised the shoulders of my dovetails. I searched high and low for got some chisels with really thin sides, and found the Ashley Iles dovetail chisels, which are really more for paring. The steel is fantastic, and I've been using them for their intended purpose, but I wanted a set to be able to chop dovetails with also. Finally I got some Ashley Iles American pattern butt chisels. They're perfect for my dovetailing purposes because they're short, which means I don't have to screw around tapping the handle of a long, unwieldy chisel 12" from the work. The steel is excellent, and the sides are ground down to a very fine land so they don't bruise the shoulders. When I need to fine tune something, I use the paring type. There's more than one way to skin that cat, and I'm still trying new things. I like to use a coping saw, but you can't do that on half-blind dove tails.

The butt chisels are very thin, but are plenty strong enough really for most purposes. I wouldn't chop mortises with them, but then, that's why we have sturdy mortise chisels. The long and the short of it is, there's no chisel that will be perfectly suited for every task. I still use my beater Stanleys--on drywall, masonry, all sorts of terrible abuse. They take a lickin' though and still sharpen up suitably well for their purposes.

Which bevel edge chisels are you working on btw? As you can tell I've had a long, bumpy journey am happy to trade experiences and war stories.

[Dan S]

Which bevel edge chisels are you working on btw? As you can tell I've had a long, bumpy journey am happy to trade experiences and war stories.

I just purchased a set of the new Stanley sweetheart chisels, and I'm in the process of flattening the backs. I'm going to grind them to 30 degreees for general bench work, and then regrind my Narex set to 20 degrees for paring duty. All my dovetails have been cut my machine so far, but later this year I want to try my hand at hand cut ones.

I have the tools to make my own chisels if i really want to, so that's why I was doing research. It seems to me like the only thing that would really matter is that the side bevel was more acute than the dovetail your trying to clean out, this would let you get all the way down into the corner.

[Jonathryn]

Do let us know what you think of the Stanleys. I have a sneaking suspicion they're using that really nice Sheffield steel. If they're tempered correctly, I'll bet they'll be outstanding. Kinda wish they'd made 720s instead of 750s. I've been thinking of making some really long, thin crank-necked paring chisels myself, but have so many saw projects going . . . .