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 (see photo). In this project, the groove is “the thing itself” that’ll guide your cuts.
Make the grooves on the tablesaw with a dado set. It’s a simple set-up: the groove is 3/8-in. wide, 3/8-in. deep and 3/8-in. 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 the stiles.
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 fence board.
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) 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-in. deeper than the length of the tenons (Photo 5).
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LEG AND RAIL JOINTS
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THE GROOVE’S THE THING. Its size and location determine where the mortises will go, so here’s the place to start. |
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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. |
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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. |
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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. |
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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. |
Hope Chest
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Tools, Materials, & Sources
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Exploded View of Hope Chest
The Grooves & Mortices
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The Tenons
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The Tenons (Continued)
The Stiles & Panels and The Top & Bottom
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Assembly
Project of the Month • Frame and Panel Hope Chest • February 2000
© 2000 American Woodworker