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Ray Iles revives a long-vanished,
Photocopying is when a toolmaker creates something that looks like a bevel-edge chisel you'd see in a catalog, but the chisel lacks critical details that make it do chisel-like things. And with each generation of tool, the photocopy degrades in quality until you finally find it in the home center's tool crib by the laser levels. Chances are the unbeveled side of the tool will be horribly out-of-flat. The chisel's side bevels will be entirely too thick to allow the tool to cut a dovetail. The handle will have the silhouette of a wooden handle, but it will be made with a heavy plastic, making the chisel too top-heavy to control when holding the tool by the blade. So it's no small wonder that beginners get frustrated when their home-center chisels don't work. After a failed chisel session, beginners either turn to old chisels that were made correctly, or perhaps they find one of the few modern makers that haven't forgotten how to make a chisel, or they give up on handwork.
This particular pattern of
mortising chisel – sometimes called pigstickers – hasn't been
manufactured for many years. It looks primitive at first
glance , like a cartoon thug's knife. But on close
examination, it's a tool of much subtlety. And so I had to
get re-acquainted with the mortise chisel to find out why it
works so well and explore the almost-forgotten techniques for
wielding them. Unlike the sash mortising chisels and firmer chisels that are labeled mortising chisels these days, the Ray Iles tools are massive and heavy. The six tools Iles offers are more than 12" long – about half the tool is the blade; the other half is the beech handle. Both halves are equally important to the function of the whole. The blades (offered in widths from 3/16" to 1/2") are remarkably thick at the tool's bolster (almost 3/4") and this thickness tapers as you approach the shallow 20° primary bevel. The cutting edge of the tool is ground at a stout and appropriate 35° secondary bevel. One nice aspect of all this blade geometry is that you can use the 20° bevel as a depth indicator. When all of the bevel is buried in the mortise, your mortise is a shade more than 1-1/4" deep, which is the typical depth used with 3/4"-thick stock. As you sharpen the primary bevel back, this will change slightly, but I don't suspect you'll be sharpening these much.
Also worth noting: One of the narrow chisels (that 1/4" again) was ground initially out of square, and one of the larger tools (the 7/16") had some chips in its edge. Both of these needed a brief trip to the grinder before honing. Note that the top surface of these chisels is domed, and that's the surface that will contact your grinder's tool rest. The doming isn't a problem as long as you are aware of it as you begin grinding. If you sharpen freehand, you're home free at this point. If you use a honing guide, you might be scratching your head as you head into honing. The tools will kinda fit in the garden-variety side-clamp honing guides with some fiddling, but they are too big for other honing guides in our shop. The VERITAS honing guide (the old one; not the new Mk. II) holds the tools reasonably well, and that's the guide I ended up using the most. After sharpening them up, I can report that the D2 seems worth it. Even after a whole cabinet's worth of mortises, for example, the edge to the 1/4" chisel looked and felt like it was still freshly sharpened. My Sorby mortisers (which I have since given away) would not have survived half that much work before crumbling like tinfoil. The final detail worth
noting is that the blade is not rectangular in
cross-section. The flanks are tapered (I measured
the taper as varying between 1° and 2°). This taper
is present on quality older tools and missing on
later tools and every modern chisel I've
encountered. The taper helps the chisel
release when you pull it out of a deep cut. It also
makes it easier to lever the waste out in my
experience. And the taper has no disadvantages that
I can discern. The chisel does not twist in the cut
at all.
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With
all the fancy steels and CNC equipment available these days,
it's both amusing and pathetic that some toolmakers cannot
manufacture a functional hand tool. The problem, I believe, is a
phenomenon called "photocopying."
