Why Four Chisels Beat a Tin of Twelve

Walk into any tool shop and you will find chisel sets of twelve, sixteen, even twenty pieces, neatly nested in a wooden case. They look like tremendous value. In practice, most contain four or five sizes you will use constantly and a long tail of narrow blades that spend their lives untouched. You are paying for steel and grinding you do not need, and the money would be better spent on fewer chisels of genuinely good quality.

A chisel is a simple tool, but making one well is not cheap. The steel must be hard enough to hold an edge in oak, yet tough enough not to chip when you lever out a waste block. The back must be flat and the bevel ground true. When a manufacturer sells twenty chisels for the price of four, something in that list is compromised, and it is usually the steel. Buy four good ones instead and add to the set later as your work demands it.

The Sizes Worth Owning

For most furniture-scale work, 6mm, 12mm, 19mm and 25mm — roughly 1/4in, 1/2in, 3/4in and 1in — will cover the overwhelming majority of joint cutting and paring tasks. If you can only stretch to three, take the 6mm, 12mm and 19mm.

• 6mm: cleaning out the corners of dovetails, small mortises, and fiddly work around repairs or inlay.
• 12mm: the workhorse. Hinge mortises, chopping waste between saw cuts, general paring, and anything where you need control more than power.
• 19mm: larger mortises, cleaning tenon shoulders, trimming end grain, and shifting material without reaching for a bigger blade.
• 25mm: housing joints, heavy paring, flattening the bottoms of shallow recesses, and tidying board edges.

Consider the shape as well as the size. Bevel-edged chisels, with their slim, tapered sides, get into dovetail corners and let you pare at an angle without bruising the surrounding wood. Firmer chisels, with square, thicker edges, are stronger and better suited to mortising with a mallet. A set of bevel-edged chisels will serve a beginner best.

Reading the Steel Before You Buy

Steel quality is hard to judge from a description, but there are things you can check in person.

• Weight and density: a good chisel feels solid in the hand rather than hollow or tinny.
• A flat back: hold a rule against the back of the blade. It should sit flat. A back that rocks or shows a hollow means hours of lapping before the tool is usable.
• An even grind: the primary bevel should be symmetrical and clean, with no blue or purple discolouration near the edge, which signals the steel has been overheated and its temper ruined.
• The file test: if you are allowed, draw a fine file across the bevel near the edge. On properly hardened steel the file skids; on soft steel it bites and cuts.
• Avoid stainless steel: it resists rust but struggles to take and hold the keen edge that woodworking demands. High-carbon steel is what you want.

Handles, Hoops and Handling

The handle matters more than most beginners expect. You will grip it for hours, and one that is too chunky, too square or too slick will make accurate work harder than it needs to be.

Hardwood handles in ash or beech absorb the shock of mallet blows and sit comfortably in the hand. Modern synthetic handles are perfectly serviceable and shrug off damp workshops, but choose ones with a slight taper rather than a plain cylinder. Look for a metal ferrule where the tang enters the handle — this stops the wood splitting under load — and a hoop or domed striking face if you plan to use a mallet. Socket chisels are worth considering too, because a worn handle can simply be replaced.

Second-Hand Chisels and What to Avoid

Some of the best chisels in circulation are old ones. Car boot sales, house clearances and market stalls regularly turn up chisels made fifty or a hundred years ago from genuinely excellent steel, often for a few pounds each. Check the following before you hand over your money:

• Pitting and rust: surface rust comes off easily; deep pitting near the cutting edge will not.
• Blade length: a blade ground down to a stub has lost its tempered section and will not hold an edge.
• Bends and twists: sight along the blade. A bent chisel can sometimes be straightened, but it is rarely worth the effort.
• Cracked handles: a new handle is a ten-minute job if you have a lathe or a spokeshave, so do not walk away over a split, but do factor it in.

Sharpening: The Cost Nobody Mentions

Whatever you spend on chisels, set aside a similar amount for sharpening. A blunt chisel is a dangerous chisel, and a cheap one sharpened properly will outperform an expensive one left dull. You will want a coarse diamond stone or a bench grinder for reshaping bevels, a combination waterstone around 1000 and 6000 grit, a honing guide if you find freehand angles difficult, and a strop for the final polish.

The first job with any new chisel, second-hand ones included, is to flatten the back. This is tedious, unglamorous and absolutely essential — without a flat back you will never get a keen edge, because the two surfaces must meet cleanly. Once that is done, a primary bevel around 25 degrees with a small secondary bevel at 30 degrees will handle almost everything. Ten minutes of maintenance every few weeks will keep a modest set of chisels working beautifully for decades, which is a far better investment than a large case of tools you never quite get round to sharpening.