I used to struggle with mortise and tenon joinery. I tried every new
system that came along, but they all seemed way too complicated. One day
a friend of a friend walked into my shop, said “Throw away those fancy
jigs!” and showed me an elegant way to make these classic joints. This
blanket chest is the ideal project to showcase this technique.
One of the ways I used to get into trouble with joinery was to
constantly measure everything. No more. Whenever possible, I use “the
thing itself” to guide my cuts, especially in mortise and tenon work.
That is, I use an object, not a ruler, to measure directly from one
thing to another. Settle on the most important sizes first, make the
pieces and then everything else falls into place.
You’ll see how fool-proof the system is in building this blanket
chest. The design utilizes a form of frame and panel construction that
goes back hundreds of years. This joinery has proved to be durable and
reliable, so if you’re thinking of making an heirloom project, here’s
one that will last many generations.
Tools and materials
You should have some experience
milling rough lumber straight and
square before tackling this project.
You’ll need a jointer and a planer to
prepare the wood, a carbide-tipped
stack dado set to cut grooves and
tenons and a miter gauge you can
trust to make square cuts. I prefer
a mortising machine for its speed
and accuracy, but you can use a
plunge router or a drill press to cut
You’ll need three different thicknesses
of rough hardwood. I used
Pennsylvania cherry, which is easy
to work and available in both rift
and plain sawn boards (see Sources, below). The legs are made of 8/4
stock and require about 10 board
feet of lumber. The rails and stiles
come from 5/4 stock and you’ll
need about 30 board feet. I used the
straight grain of rift-sawn wood in
the legs, rails and stiles to offset the
plain-sawn top and panels, which
required about 20 board feet of
4/4 wood. I used about 12 board
feet of white pine for the bottom
boards and back panels partially
for economy, but mainly because I
like the smell.
Begin by milling all the legs and
rails to thickness, width and length
(see Cutting List, below). Be sure to
cut the rails to their overall length,
which includes both tenons. Mill the
stiles to thickness and width, too,
but leave them a bit long for now.
Make a few extra short rails to use
as test pieces down the road.
I’ve learned the hard way that it’s
best to make the mortises first,
then size the tenons to fit them.
Begin mortising by making the
grooves, because they define the
sides of the mortises. In addition,
the depth of the grooves
defines one end of the mortises
(see Fig. B). Notice how the bottom
of the groove becomes the
edge of a tenon. In this project, the groove
is “the thing itself” that’ll guide
Make the grooves on the tablesaw
with a dado set. It’s a simple
set-up: the groove is 3/8" wide,
3/8" deep and 3/8" from the fence
(Fig. A, Detail 2). Mark the face
side of each piece before you
begin to cut. The face side always
goes up against the fence. Groove
one edge of all the rails, including
the test pieces, and both edges of
Cut one stopped groove in each
leg (Photo 1). You’ll have to limit
the length of the groove because
it stops at the bottom edge of the
lower mortise (Fig. A). Clamp
a stop block to a long auxiliary
Reset the fence to the left side
of the saw blade to cut the other
groove in each leg. Use one of the
legs as a measuring tool to position
the fence. Unplug the saw,
nestle the grooved edge of a leg
right on top of the dado set (face
side pointing to the left) and snug
up the fence. Run the other face of
each leg up against the fence when
you cut the groove (Photo 2).
Next, cut the wider groove that holds the bottom in place (Fig. A, Detail
5). It will become the lower edge of a tenon.
Use the top of the rail as your reference edge.
The tenons on these lower rails fit exactly
between the two kinds of grooves you’ve
made (Fig. B).
Deepening parts of the grooves creates the
mortises. Where exactly do the mortises
go? Pick up any rail and you’ve got the
information right in your hand.
Lay the top rail on a leg and you’ll be using
“the thing itself” (Photo 3). Place the rail so
it barely hangs over the leg (Photo 4). Just
follow the lines down from the grooves (Fig.
B). Cut a piece of wood the length of the
panel opening (Cutting List, below) to precisely
position the lower rail.
Once you’ve marked one leg, clamp all the
legs together and transfer the mortise marks
from the first leg to the others. Make the
mortises 1/8" deeper than the length of the
tenons (Photo 5).
Having made the mortises, cut the tenons to
fit them. You won’t have to measure. Simply
use the parts you’ve got so far. To get started,
install the dado set with all its chippers and
raise the blade the height of the outer wall of the groove (Photo 6). This is the
same distance as the tenon’s shoulder,
because this is a flush joint.
Try this dado setting on a test piece
(Photo 7). Adjust the height of the
dado set until the face of the tenon is
exactly in line with the groove (Photo
8). Then cut both ends of all the long
and short rails. You’ll be revisiting this
setting later, so improvise a simple
paper indicator to record it (Photo 9).
Cutting the opposite face of the
tenon requires lowering the dado set.
Leave the fence where it is. Place a rail
with its face side up next to the blade.
Lower the blade until it lines up with
the bottom wall of the groove, just as
you did before. Cut a test piece and try
it in the mortise (Photo 10). This is a
finicky setting, so it will take a number
of attempts to get it right. Record this
blade height, too.
Saw each haunch on the bandsaw
(Photo 11). Lay it out directly from the
mortise (Fig. A, Detail 3). The haunch
serves three purposes: it fills in the
groove; adds more gluing surface; and
widens the tenon to fight racking of
the case. It’s great. I use a haunched
joint in table legs, too.
Finish the legs by beveling the
inside corners (Fig. A, Detail 3). Tilt
the blade away from the fence at a
15˚ angle. Clean up the saw marks
on the jointer.
The stiles and panels
There’s one more fussy operation
to do, and that’s fitting the stiles
between the rails. You might think
this is asking for trouble, but it only
takes a minor adjustment of your
fence to get it right.
The first thing to figure out is
the exact length of the stile, which
includes two tenons. Assemble the front
of the chest, without glue, by clamping
together two long rails and two
legs. Measure the opening and add the
length of the two tenons (Fig. A, Detail
6). You can do this without a ruler by
marking directly on a stile.
Cut all the stiles to length. Then cut
a complete tenon on one end of each
stile. Because you recorded the two
heights of the dado set to make a tenon,
this should be easy. If you use all the
dado chippers, add a wooden face to
Fit the stiles to the opening when you cut the
tenons on the other end. You can fine-tune the
stile’s length between its shoulders by moving
the saw’s fence.
Now you can precisely mark the mortises
directly from the tenons (Fig. C and Photo 12).
Take the front apart and make three spacers the
width of the panel openings. Mark alongside
the tenons on one rail, then clamp all the rails
together and transfer these marks across them.
Cut the mortises.
You can size the panels by another method
of direct measurement using “pinch sticks”
(Photo 13). They’re two narrow sticks, each a
bit shorter than the opening. Reassemble the
front with the stiles in place. Butt one end of
each stick into opposite grooves and pinch them
together with a small spring clamp. Wiggle the
pinch sticks out of the opening and you’ve got
another “thing itself.”
Cut the panel 1/16" smaller in width and
height than the length of the pinch sticks. Shape
the panels with a 3/4" dia. round-nose bit on a
router table equipped with a tall fence (Fig. A,
Detail 2. Also see Sources, at right for the bit).
Sand and apply a finish to the outside of the
panels before you glue up the case.
The top and bottom
The bottom is notched around the legs. Don’t
mess around with measuring angles to make
the notches. Here’s a direct method:
Put the whole chest together without glue
to figure out exactly how big the bottom needs
to be. Measure from the bottom of one groove
to the opposite groove as you did for the panels.
Make the bottom from three loose boards
connected by tongue and groove joints (Fig. A,
Detail 2). Cut the bottom boards to length and
width, put them together on a flat surface and
place the chest on top of them. Scribe around
the legs onto the bottom, remove the bottom
from under the chest and cut out a notch in
each corner on the bandsaw (Fig. A).
Glue up the top and cut it to fit the chest.
Rout a molding on the front edge and ends, but
not the back (Fig. A, Detail 1).
Glue up the front and back. Plane down the
top rails so they’re even with the legs (Photo
14). Cut the double-deep mortises for the
hinges on the back rail (Fig. D). Set in the dowel pins and cut them off flush
(Photo 15). Plane, scrape or sand
all the joints flush.
Glue up the entire case (Photo
16). Plane the top of the side rails
even with the legs. To install the
hinges, lay the case on its back
supported by boards that are the
same thickness as the top. Butt the
top up to the back rail and mark
the positions of the hinges (Photo
17). Install the top and add two
spring-loaded lid supports (see
Sources, below right) to prevent
the top from squashing a kid’s
fingers as it closes.
Cherry naturally darkens with
age, especially under a thin finish.
Patience, rather than stain, will
yield the best results. If you oil
your chest it will turn a beautiful
deep color in a year or two. You
can leave the interior of your chest
unfinished, or use shellac or wax
to avoid unpleasant odors.
(Note: Product availability and costs are subject to change since original publication date.)
Groff and Groff Lumber,
groffslumber.com, 717-284-0001, Pennsylvania cherry.
Woodcraft, woodcraft.com, 800-225-1153, Cherry dowel rod, #50B02.
MLCS, mlcswoodworking.com, 800-533-9298, 1/2” Shank 3⁄4” dia. Round-nose Router bit,
#8747; 1/2” Shank Round-over Router Bit,
#8655; 1/2” Shank Tongue and Groove Router
Lee Valley, leevalley.com, 800-871-8158, 2" x
1-1/2" Plain Hinges (pair), 01B01.07.
Rockler, rockler.com, 800-279-4441, Lid supports,
Woodcraft, woodcraft.com, 800-225-1153,
Lynx Flush Cut Saw, #147417.
Fig. A: Exploded View
Fig. B: Leg and Rail Joints
Fig. C: Joints Between Stile and Rail
Fig. D: Detail of Hinge Mortise
This story originally appeared in American Woodworker February 2000, Issue #78.
Click any image to view a larger version.
The tenons of this
chest line up exactly
with the grooves that
hold the panels. This
simplifies laying out
the joints. Cut the
grooves first and the
rest naturally follows.
1. The groove’s the thing. Its size and location determine where the mortises will go, so here’s the place to start.
2. Saw one stopped groove in each leg with a dado set. The end of the leg is marked with lines identifying the two face sides. Put the face side against the fence. Re-set the fence to the other side of the saw blade to cut the second groove.
3. Put away your ruler and lay out the mortises directly from the rails. This is much easier and more accurate than using a bunch of numbers. Sketch in the tenon on the end of the rail and extend lines down onto the leg. To position the bottom rail, make a spacer that’s the exact length of the panel opening and place it between the rails.
4. The top rail should extend about 1⁄32-in. above the leg. This makes your life a whole lot easier because after glue-up you are able to plane the rail to meet the leg, rather than trying to plane the end grain of the leg.
5. Mortise the legs. A mortising machine with a tuned-up bit and chisel makes short work of these deep mortises. The groove locks in the chisel, producing a mortise with perfectly straight walls.
5 Ways to Soup Up Your Mortiser
These machines can cut accurate mortises incredibly fast. Here are five tips to make a good machine even better for any project:
1. Install a wider and longer support table.
2. Fasten the machine to your workbench.
3. Add a homemade riser block to the machine to accommodate wide legs and rails.
4. Lock the work in place with a clamp.
5. Blow out the chips with compressed air.
6. Set the dado blade height for cutting the tenons. It should be even with the groove in a leg. Fine-tune the setting by trial and error. It’s best to start out low and work your way up.
7. Cut a cheek on the face side of a test piece. Set the saw’s fence to the length of the tenon. Take two passes across the tenon’s face to remove all of the waste. Make sure the end of the rail is tight against the fence during the second pass.
8. Check the accuracy of your cut by holding a tight-fitting stick of wood in the groove. Run your finger across the tenon and stick. They should be perfectly even.
9. Save this setting! You’ll need it for cutting tenons on the stiles. Mark the position of your hand wheel to record the height of the dado set. Then lower the dado set and cut the back side of each tenon.
10. Size the tenon by inserting the test piece into the mortise. If it takes a mallet to get the tenon into the mortise, the fit is too tight. If the tenon drops into the mortise with ease, it’s too loose. The correct fit is somewhere in between. Adjust the height of the dado blade to find that fit, then cut the back side of all the tenons.
11. Bandsaw the notch that forms the haunch. A fence helps keep the cut straight, but you can also cut freehand, following a pencil line. Clamp a board onto the fence and raise it above the bandsaw’s table. When the waste piece falls out of the notch, it will slide underneath the board and won’t get trapped between the blade and the fence.
We accidentally cut off the haunch on one tenon. Here’s an easy fix: You can insert a new one! Cut a dado right in line with the tenon and glue in another haunch.
12. Lay out the mortises in the long rail directly from the stiles. Cut spacers that are the width of the panel opening and place them between the stiles. Then draw a pencil line along the side of each tenon.
13. Pinch sticks directly measure the size of the panels. Misreading a ruler can get you in trouble, but these sticks are always accurate.
14. Plane the top rail flush with the leg after you glue up the chest’s front and the back. This beats planing down the end of a leg to meet a rail!
15. Cut off the dowel pins that lock the joints with a Japanese-style flush-cutting saw (see Sources, below, left). Its teeth have no set, so they won’t cut into the wood around the pins. Glue the pins in the front and back assemblies and saw them flush before you glue up the entire case.
16. Slip in the bottom boards during the final glue up. They fit in a groove that goes all the way around the inside of the chest. Tongue and groove joints hold the boards together so you don’t have to glue them to each other.
17. Position the hinges on the top and mark the screw holes with an awl. Each hinge sits snugly in a mortise that’s as deep as the thickness of a doubled-over hinge, so there’s no need to mortise the top.