Half-Blind Dovetails: Drawer Front Joinery

Half-blind dovetails are the standard joint for drawer fronts. The tails are cut on the drawer side, the pins in the drawer front, and the joint stops short of the front face. From the front, the drawer looks like a solid panel; the joinery is visible only from the side and inside. That hidden lap is what separates the half-blind from a through dovetail, where both pin and tail boards show end grain on both faces.

The half-blind exists because a drawer front has a public face. A through dovetail would put end grain and saw marks across the front of every drawer, which is unacceptable on furniture where the front is the show surface. The half-blind keeps the front clean while retaining the mechanical interlock that resists the pull and racking a drawer sees. The trade-off is that the joint cannot be cut straight through, so the saw and chisel must work at an angle and stop at a line.

How the joint is arranged

The tail board is the drawer side. The pin board is the drawer front. The tails themselves are cut right through the drawer side, exactly as for a through dovetail; what makes the joint half-blind is the front. There the sockets that receive the tails stop short of the show face, leaving a solid lap of wood in front of them. Those sockets are blind: they have a floor and a back wall, and the tail ends seat against the lap.

Two gauge settings define the joint. The first is the socket depth: how far the tails reach into the front, which is the front’s thickness minus the lap. That setting marks the baseline on the drawer side, all the way round, and the matching line on the end grain of the front. The second is the thickness of the drawer side, which marks the baseline on the inside face of the front. Mark both with a marking gauge, not a pencil. A sharp gauge leaves a scored line the chisel can register against; a pencil line does not.

Cutting by hand

Most hand methods cut the tail board first. The tails are easier to lay out and saw because the cuts run straight through, and once they exist they can be used to transfer the pin layout directly to the front. That transfer is the reason for the order: it removes the need to measure pin spacing and guarantees the two boards match.

Tails

Mark the tail spacing on the end grain of the drawer side. A common approach is to use a dovetail template or to step off the spacing with dividers, but any layout that produces consistent tails and sockets at least as wide as the chisel will work. Extend the lines down both faces to the baseline.

Saw the tails as for a through dovetail. The saw is held vertically and the angle is in the layout; cut on the waste side of the line and stop at the baseline on both faces.

Chop the waste between the tails from both faces, working halfway in from each side so the baseline does not break out. Pare the end-grain shoulders flat and square. The tail board is the easy half; the difficulty of the joint is in the front.

Pins

The pins are cut in the drawer front. The saw cannot go through the front, so the cuts are made at an angle: the saw starts on the end grain and is tipped down until the plate meets the gauge line on the inside face. This is the operation that separates a clean half-blind from a ruined drawer front. The saw must stop at the lap line. Sawing past the baseline puts a cut into the visible face, and no amount of paring removes it.

A common method is to clamp the front in a vise with the inside face up and the lap line toward the user, then saw with the saw plate angled so the toe of the saw is lower than the handle. The cut is short and the angle is steep; light strokes at the start establish the kerf without overshooting.

After sawing, chop the waste from the sockets. Work from the end grain toward the lap line, removing the bulk with a chisel and then paring the floor flat. The floor of each pin socket is the surface that seats against the tail; it must be flat and square to the sides, not rounded or sloped.

Transfer and fit

With the tails cut, place the tail board on the end of the front, register it against the gauge line, and mark the pin positions with a knife or a fine pencil. Saw and chop as above. Test the fit by assembling dry. The joint should go together with hand pressure and no hammer. A joint that must be forced will split the pin board; a joint that drops in with no resistance will be loose.

A good fit shows no gap at the lap line when viewed from the side. The shoulders of the tails should meet the front with no visible opening. From the front, the lap line should be invisible after final planing; any saw kerf that reaches the face will show as a dark line.

Cutting with a router jig

A router jig cuts both halves of the joint with a dovetail bit and a template. The work is clamped vertically and horizontally, and the bit follows a comb that sets the spacing. The jig method is faster and more repeatable than hand cutting, but it has its own failure modes: the bit can tear out the lap, the template can shift, and the depth setting determines whether the joint seats or bottoms out.

Set the bit depth so the tails stop at the lap line. Cut a test joint in scrap of the same thickness before touching the drawer parts. The test joint should assemble with hand pressure and show no gap at the lap. If the joint is tight, reduce the depth in small increments; if loose, the bit is too shallow or the template has moved.

Tear-out is most common on the outside face of the drawer side, where the bit exits the tail cuts. A backing board clamped tight against that face prevents it; a loose backing allows the bit to lift fibres.

Where the joint fails

The most common failure is sawing past the baseline into the visible face. It happens because the saw is angled and the user is watching the kerf on the end grain rather than the gauge line on the inside face. The saw plate is thin and the lap is short; a single stroke too far puts a kerf across the front. The fix is to stop the saw before the line and finish with a chisel, or to clamp a stop block at the lap line so the saw cannot advance.

The second failure is a socket floor that is not flat. A rounded or sloped floor holds the tail away from the front, leaving a gap at the lap. The cause is chopping with a chisel that is not sharp or paring at an angle rather than flat against the floor. A sharp chisel and a light paring cut, checked with a straightedge, prevent it.

The third failure is tear-out, most often from a dull bit or chisel, or a backing board that is not tight. On the front, the corners of the sockets next to the lap are short grain, and levering the chisel against the lap instead of paring breaks them away.

Comparison

The mistake most people make

The mistake is treating the half-blind as a through dovetail with a stopped cut. The two joints look similar in layout, but the half-blind has a lap line that must be respected on every cut. The through dovetail allows the saw to exit the far face; the half-blind does not. People saw past the baseline because they are used to the saw running free, and because the lap line is on the inside face where it is easy to ignore while watching the end grain. The fix is not more care in general; it is a physical stop—a clamp, a block, or a gauge line deep enough to catch the saw—so the cut cannot advance past the lap.

Related

For the through version, see dovetail joints. For paring and chopping, see sharpening chisels.