Demilune 4. Apron Joinery. Curved Apron Tenon. Bridle Joint Legs. Bridle Joint Front Apron

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Katherine Nicholson
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Demilune Email 4 Apron Joinery There are two types of joints used in connecting the aprons and legs.

Be careful not to get the mortises for the front and rear aprons confused. Mark them carefully then cut the rear leg mortises.

Lay a straightedge on the major axis of the ellipse to establish the shoulders of the tenon, and mark them with a knife.

Mill this cheek to size. Establish the location of the top of the tenon and cut it down about 1/2". Mill the inside cheek for a sliding fit into the mortise.

Bridle Joint Legs The bridle joint in the legs is a simple notch, parallel to the apron with a depth equal to the apron height, a setback from the leg front of 3/8 and a width of 1/2".

The table saw will not cut the notch deep enough, so use a cutting gauge to extend the notch sides to the full length and cut the remailing sides on the bandsaw.

1 Demilune 4 Apron Joinery There are two types of joints used in connecting the aprons and legs. The rear legs use conventional mortise and tenon joints, while the front legs use the less conventional bridle joint. The first step is to mortise the rear legs. Be careful not to get the mortises for the front and rear aprons confused. Mark them carefully then cut the rear leg mortises. The plans call for a 1/2" step at the top of the mortise and no step at the bottom. Curved Apron Tenon The next step is to fit the tenons for the curved apron. Lay a straightedge on the major axis of the ellipse to establish the shoulders of the tenon, and mark them with a knife. Then transfer this line down the sides of the apron, establishing the tenon cheeks. The leg setback for the outside cheek should be 1/8 plus veneer thickness, or about 5/32. Mill this cheek to size. Establish the location of the top of the tenon and cut it down about 1/2". Mill the inside cheek for a sliding fit into the mortise. Repeat these steps for the opposite tenon. Bridle Joint Legs The bridle joint in the legs is a simple notch, parallel to the apron with a depth equal to the apron height, a setback from the leg front of 3/8 and a width of 1/2". A tenon jig is useful here. The photo shows a simple homemade jig to cut this notch. First cut the front edge, then using the same face against the fence adjust the notch width to 1/2". The table saw will not cut the notch deep enough, so use a cutting gauge to extend the notch sides to the full length and cut the r ing sides on the bandsaw. You could also cut the whole notch on the bandsaw if it is tuned to cut without drift. Finally, finish the notch bottom with a coping saw and chisel. When cutting the front leg notches, make a short leg of the exact leg cross section and notch, about 10 long. This will be used in locating the cutouts in the apron to fit the legs. Bridle Joint Front Apron Fitting the square legs to the curved apron requires some special attention. We need dados in the front and rear of the apron which align to receive the square leg. The first step is to locate the front dado. The outside corners of the front dados are 7-3/8 from the front corner of the apron tenon shoulder. Locate and mark this point on the top of the apron.

Demilune Email-4 Page 2 Bruce D. Wedlock Next cut about 2 off the rear stub of the short leg.

Place the short stub against the back of the apron with one edge at the above located mark.

Drop perpendicular lines to mark the edges of the dados.

lines to insure the leg will fit the dado tight.

Chisel bevels to the line and saw to a depth of 1/4" less the veneer thickness.

2 Demilune -4 Page 2 Bruce D. Wedlock Next cut about 2 off the rear stub of the short leg. This is now the gauge to lay out the sides of the front and rear dados. Place the short stub against the back of the apron with one edge at the above located mark. Draw a line on each side on the apron top. These are the edges of the front and rear dados. Drop perpendicular lines to mark the edges of the dados. Next use a marking knife to mark the vertical edges of the front dado a hair less than the lines to insure the leg will fit the dado tight. Err on the side of too tight; that is much easier to correct. Chisel bevels to the line and saw to a depth of 1/4" less the veneer thickness. Extra saw cuts in the waste area eases removal of stock. Finish the depth with a router plane set to the desired dado depth. This produces a plane surface parallel to the apron face. When finished, the leg should fit the dado tight.

Demilune Email-4 Page 3 Bruce D. Wedlock We now need to establish the depth of the rear dado.

Remove the waste with saw and chisel until you get close, but do not go to the full depth. The next step is to fit the width of the rear of the leg to the dado edges.

Note this fit is not visible so planing the leg is easier than trimming the dado s edge.. Finally deepen the dado for a sliding fit with the leg. This is best done with a shoulder plane.

3 Demilune -4 Page 3 Bruce D. Wedlock We now need to establish the depth of the rear dado. This is done by placing the short leg in the front dado and marking the inside edge of the stub end on the top of the apron. This establishes the dado depth. Remove the waste with saw and chisel until you get close, but do not go to the full depth. The next step is to fit the width of the rear of the leg to the dado edges. This is easily done by using a block plane to remove extra wood from the leg edges until a smoot fit is achieved. Note this fit is not visible so planing the leg is easier than trimming the dado s edge.. Finally deepen the dado for a sliding fit with the leg. This is best done with a shoulder plane. All you need is a fair sliding fit as the leg s position will be established by front dado s depth. Rear Apron Tenon The tenons on the rear apron need to be carefully laid out since their shoulder spacing is governed by the front apron tenons. Dry fit the rear legs and front apron place the rear apron against them. With a marking knife locate the tenon shoulder on each end of the rear apron. Working from that edge as the reference surface lay out the tenon shoulder around the rear apron with the knife. Mill the rear tenon cheek to make the rear apron flush with the outside of the rear leg. Work to about 1/16 of the shoulder; the shoulders will be cut by hand as the last step. Cut the tenon top back to fit the mortise. Next mill the remaining cheek for a sliding fit in the mortise. Finish the tenon by paring the tenon shoulder to the marking knife line. Tapered Legs With all the leg joinery finished, the legs can now be tapered. There are a number of ways to taper a leg, but Steve Latta s jig described in Fine Woodworking Nov/Dec 2012, pp 30-35, is strongly recommended. It is truly foolproof. The front and sides of the legs are tapered; the rear sides remain straight. Start by cutting the legs to their final length of 28 and laying out the 3/4' square end of the taper on the foot. Be careful that the tapers are cut on the front and sides of the legs.

Demilune Email-4 Page 4 Bruce D. Wedlock Mount the leg in the tapering jig.

The actual cut should begin an inch or so below the final edge of the taper. Note: it is not necessary to keep the leg axis horizontal.

To finish the tapers, plane the machine marks away and adjust the start of the taper to 1/2" below the apron.

As you plane the machine marks, the edge of the taper is shown by the edge of the chalk. Plane until the chalk line is at the pencil line.

Start with a 3/4 thick blank a bit wider than the apron and a couple of inches longer than the center portion.

This will produce a caul that will bend to the curve of the center apron.

4 Demilune -4 Page 4 Bruce D. Wedlock Mount the leg in the tapering jig. Set the leg about 1/32 inch back from the cutting edge to allow for some stock to remove with a plane. The actual cut should begin an inch or so below the final edge of the taper. Note: it is not necessary to keep the leg axis horizontal. A tapered side can lie directly on the jig. Complete the cut. To finish the tapers, plane the machine marks away and adjust the start of the taper to 1/2" below the apron. Lay out the location of the taper in pencil and use chalk to mark the area below the tenon start. As you plane the machine marks, the edge of the taper is shown by the edge of the chalk. Plane until the chalk line is at the pencil line. Veneering the Apron The first step in veneering the apron is to make a caul to clamp the veneer to the curved apron. Start with a 3/4 thick blank a bit wider than the apron and a couple of inches longer than the center portion. Use a rip blade to cut a series of cross-grain kerfs, spaced about 1/8 apart and leaving 1/8 material, the length of the board. This will produce a caul that will bend to the curve of the center apron. For the ends, you may want to rip the caul in half which makes it easier to bend over the sharper curve. For the ends it also helps to boil or steam the caul, clamp it to the apron and let it dry. It will begin to take on the shape of the curve, making clamping easier. Both oak and pine have been used for these calls with success. Assemble all the tools necessary for gluing the veneer before starting. The process moves very quickly so you want everything on hand. For adhesive, UnibondONE is recommended. It has a strong glue line and will not creep nor leak through the veneer like PVA. You will also need a notched adhesive card applicator, a J-roller, a water sprayer, the caul and clamps Fasten the apron in a vise to keep it steady for gluing and clamping.

Demilune Email-4 Page 5 Bruce D. Wedlock Trim the veneer for a 1/8 overhang.

Apply the adhesive and smooth it with a notched applicator card. Be sure to get a good coating at the edges.

Quickly spray a light coating of water on the surface to prevent the veneer from curling.

Be sure to get squeeze out at the corners and ends.

If the caul is in two halves, you can use the spring clamp to keep the veneer in position while one caul is

Blue tape will also hold the veneer in position, but apply it before spraying the water.

5 Demilune -4 Page 5 Bruce D. Wedlock Trim the veneer for a 1/8 overhang. Roughen the apron surface with a toothing plane or 60-grit sandpaper. Apply the adhesive and smooth it with a notched applicator card. Be sure to get a good coating at the edges. Apply the veneer and clamp one edge with a spring clamp to keep it in position. Quickly spray a light coating of water on the surface to prevent the veneer from curling. Press the veneer onto the apron surface with a J-roller, squeezing out excess glue. Be sure to get squeeze out at the corners and ends. Apply the caul and fasten with clamps to insure a good mating joint between the veneer and apron. If the caul is in two halves, you can use the spring clamp to keep the veneer in position while one caul is clamped, and then fasten the second caul. Blue tape will also hold the veneer in position, but apply it before spraying the water. Be sure the caul clamps the ends of the veneer tight to the apron. When dry, remove the cauls and trim the veneer flush with the apron edges. A flush saw works best for this. A sharp chisel is not a good choice for trimming as the grain around the eyes is gnarly, causing an eye at the edge to pop right out. A fence can be clamped to guide the saw for the leg dados. If you don t have a flush saw, saw close and finish with a file or sandpaper.

The WoodWorker s Edge

The WoodWorker s Edge Draw-leaf Game Table 1. 2. Layout the area for the tenons. The tenons are 3/8 thick x 4-1/2 long x 1-1/4 deep and offset to the inside. Create the tenons using the step method to