69 - Bench Top Storage System, страница 13

couple of extra ingredients — mostly chromium and tungsten. These additions give blue steel a wider temperature range for tempering. But it also makes tougher steel, which is more suited to working with abrasive woods like teak. But sharpening takes longer than white steel.

Having just a thin layer of hard steel means that there isn't a lot of difficult material to remove when sharpening the bevel. And the hard steel is only on die cutting edge — right where you need it.

The other half of sharpening is flattening the back. Here too, chisel makers have made things easier. If you flip a chisel over, you can see why — the back of the chisel has been hollowed out, reducing the amount of steel to remove, as in the photo above right.

You may notice that some wider chisels have a single hollow in the back while others have two or three. Having more than one hollow doesn't really affect the strength of the chisel. Some woodworkers say it comes in handy when you're using a wider chisel on a narrow workpiece. The ribs help W keep the chisel flat.

Length - Another thing ./ you'll notice about Japanese

The trutii is that, used properly, they can do any job you ask them too.

That's because they're not made entirely of hard, brittle steel. If you look at the bevel of a Japanese chisel, you can see that there are two layers of metal. A thick, top layer of softer iron or steel is "forge-welded" to a thin, bottom layer of hard steel. This helps back up the steel to keep the blade from chipping or cracking.

Choices - When you read the catalogs, you'll see tiiat some chisels are made of "white steel" and others are made of "blue steel." These are simply designations of different types of hard steel. The names actually come km the color of paper the steel is wrapped in at the foundry. But what makes this confusing is that you can't tell the difference between the two by looking at them.

White steel is just a high-carbon steel. It's a little more difficult for blacksmiths to work because the temperature range that it's tempered at is very narrow. This means that it takes more time and a lot of skill to work with this steel. Some woodworkers will tell you that white steel can get sharper than blue steel but it breaks down quicker.

Blue steel on the other hand, is a high-carbon steel witii a

m Hdlowed-OutBack.

Some chisels have only one hollow, while others have two or more. The hollows maker it easier to flatten the back.

chisels is their shape. The blades are often a lot shorter than the chisels you have in your toolbox. The reason for this difference is greater control when striking the chisel. Think of it like writing with a pen. When you're writing, you hold your pen close to the point where you have more control than if you were to grab it by the end.

The chisel handles are traditionally made of wood. There are four Japanese hardwoods commonly used in the handles: boxwood, white oak, red oak, and sandalwood, as in the margin photo below.

Style - Beyond their general shape, you can choose from a variety of chisel styles, as in the photo at left. The most common are bench chisels (also called cabinetmakers' chisels), which have flat-topped blades.

Dovetail chisels are similar in size to bench chisels. But the shape of the blade is what makes them unique. The top of the chisel comes to a point, like a pyramid. As the name implies, they're designed for cutting and fitting dovetails. The sloped edges can get into tight places that other chisels can't get to.

Mortise chisels are a third type. These beefy chisels look a lot like western mortise chisels with flat sides and long blades.

A final type is the paring chisel. Unlike the others, this type is made for pushing only. The blades and the handles are much longer for

Mortise

Dovetail

more control while pushing. They're used for trimming large mortises and tenons.

A Types of Chisels. Japanese chisels come in a variety of styles depending on their use. Bench chisels (bottom) are designed for everyday work. Long-handled paring chisels (top) are designed for pushing only.

Sandle Wood

A Handle Choices.

These are the most common hardwood handles found in Japanese chisels.

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