How would you
like to assemble
cabinet without using
clamps or fasteners? That’s the
promise offered by tapered sliding
dovetail joints. The joint
consists of a tapered socket cut
into the face of one piece and a
tapered dovetail cut on the end
of the other. The pieces simply
slide together (photos at right).
Like a dado joints with attitude,
tapered sliding dovetails lock
mechanically to form rigid 90-
Before reliable glues or economical
fasteners were available,
cabinetmakers relied on
these sturdy joints to connect
cabinet components. The
tapered parts must fit precisely
to create a wobble-free joint, so
cutting these joints by hand is a
real woodworking tour de force.
Fortunately, a dovetail bit, a
router table and a simple shopmade
jig make tapered sliding
dovetails much easier to master. You use the jig (Fig. A, below) to
make the sockets and the router
table to make the dovetails.
Shims make it easy to
create the tapers.
The dovetails and sockets
increase in width at the rate of
1/16-in. every 12 inches. (Both
sides of each dovetail and socket
are tapered, so each side increases
by 1/32-in.) Shims milled to 1/32-
in.-thickness create perfect tapers
on the 12-in.-wide workpieces
shown here. To maintain the taper
angle on assemblies wider or narrower
than 12-in., simply adjust the
Make the jig and rout the sockets
Use a sled to make the jig’s
tapered guide boards (Photo 1).
The sled and both guide board
blanks must be squarely cut. Mark
the taper’s 12-in. run on the sled.
Position the sled flush against a
block and a stop. Tape a shim on
the block, above the mark you’ve
just made on the sled. The shim’s
1/32-in. thickness constitutes the
taper’s rise. Butt the guide board
blank against the stop and the shim
and nail it to the sled. Cut the taper
(Photo 2). Mark the tapered edge
and the direction of its slope.
Assemble the jig (Photo 3). It
should fit snugly over the cabinet
sides. Make sure the tapered guide
boards angle outward from front to
back. The distance between the
guide boards at the front of the jig
determines the narrow width of the
dovetail socket. For example, to
make a 5/8-in.-wide socket using a
1/2-in. dovetail bit, the distance
between the faces would measure
the diameter of your router’s base
plus 1/8-in. This socket would swell
to 11/16-in. at the back of a 12-in.-
wide workpiece. Tapered sockets
(and dovetails) of this width are
perfect for the 3/4-in.-thick stock
Rout the sockets (Photo 4). The
sockets’ depth can vary. In 3/4-in.-
thick stock, 5/16-in.-deep sockets are
Rout the dovetails and fit the joints
Install the dovetail bit in your
router table. Then attach shims to an
extra long shelf (Photo 5). Use the
shelf’s extra length for test cuts while
you adjust the joint’s fit. The shims
hold the back end of the shelf 1/32-
in. away from the fence when you
rout (Photo 6).
Test the dovetail’s fit in a socket
(Photo 7). If the dovetail is too wide,
the joint won’t go together. If it’s too
slender, the shelf will slide past the
cabinet side’s front. I won’t lie. These
joints are finicky. To dial in a perfect
fit, you’ll have to be able to make
paper-thin adjustments. So when you
get close, outfit your router table with
a simple micro-adjust system that’s up
to the challenge (Photo 8).
Sliding dovetail joints don’t have
to be glued: They’re the predecessors
of knock-down hardware. But
gluing makes them stronger for the
long haul. Apply glue to the beveled
sides of the sockets. Slide in the
dovetails and tap them home (Photo
9). Give your clamps a rest.
Fig. A: Routing Jig
This story originally appeared in American Woodworker October 2007, issue #131.
October 2007, issue #131
Purchase this back issue.
Click any image to view a larger version.
In a tapered sliding
joint, the dovetail
taper from back
to front. The
parts fit loosely
at first, because
narrow front end
enters at the
As the dovetail
in the socket,
the fit gradually
result is a snug
1. Fasten the jig’s guide boards to a sled for tapering, using a block, a stop and a
shim for positioning. Butt the sled to the stop and the block. Then tape on the
shim. It’s thickness and location determine the taper’s slope. Butt the guide board to
the stop and the shim. Then nail it to the sled.
2. Taper the skewed edge of each guide
board. Holding the sled against the
rip fence skews the guide board’s back
end toward the blade. The taper is very
slight, so indicate the tapered edge and
the taper’s direction.
3. Assemble the jig around the cabinet
side. Butt everything against a block
to guarantee the jig goes together
squarely and the guide board tapers run
true. Spacers elevate the rails for fastening
the guide boards.
4. Rout the tapered sockets. Orient the jig’s front with the cabinet side’s front, so the
sockets grow wider from front to back.
5. To create the tapered dovetails, attach
shims at the back edge of each shelf.
These shims must be the same thickness
as the shim used to skew the guide boards.
6. Use a tall fence to rout the tapered
dovetails. The dovetails gradually
decrease in width from back to front,
because the shims hold the back end of
the shelf away from the fence.
7. A stop and paper shims installed
behind the fence allow microadjusting
the fence to dial in the perfect
8. The shelf fits perfectly when it can be
pushed to within 1-inch of the end by
hand. Tap it home with a mallet.
9. Gluing tapered dovetails is easy. The
glue doesn’t get forced out because the
joints stay loose until the last inch. Once
you tap them home, they’re rock-solid.