Creative Woodworks & crafts 1998-03, страница 21

the same thickness and width as your required pieces.

The rails measure nine inches from shoulder to shoulder of the tenon (see the patterns found in Full Size Pattern Section No. 2). Begin the layout by finding the center of the length of one rail. Next, divide the shoulder-to-shoulder measurement by two and put half of the dimension on each side of the center line. By starting with a center line and measuring outward, you'll avoid ending up with one short tenon. Transfer this measurement to the test rail piece with a combination square.

Set up your table saw with a dado head cutter to shape the tenons. Hint: make sure that the setup is accurate before you cut the actual project part. Fine tuning the cut now will save a lot of aggravation later!

The actual width of the tenon will be 7/16". Subtracting this dimension from 7/8" and dividing by two will tell you how high the dado head must be set above the table to make the tenon, in this case, 7/32". Next, mark this dimension on the edge of a sacrificial board that you'll attach to the fence.

Using the miter gauge as a guide, make the necessary cuts to form the tenon on both sides of the test rail. The tenon fit should be snug, but not so tight that you have to beat the joint together. To do so would produce a glue-starved joint that will eventually fail. Make any necessary adjustments to either the cutter head height or fence position to produce a good secure joint. When you are satisfied, make the cuts to form the tenons on the bottom rails {see Fig. 3).

The mating piece of the bridle joint for the top rails should now be cut. The cutter head height should be the same. The only difference is thai the tenon is cut away from the end of the rail. The extra stock will eventually be shaped to form a decorative scroll.

It is important that the 9" shoulder-to-shoulder dimension be. maintained on the top rail as well {see the pattern found in Full Size Pattern Section No. 2). In addition, the length of the tenon must match the width of Ihe leg. For this reason, accurate layout is essential.

Make the lap joints

Once all of the tenons have been cut, the legs and rails can be sanded. Care must be exercised so that you do not round over these parts and Ihus affect the fit. I prefer to sand prior to making the decorative arches and before cutting the half lap joint that allows the two rails to cross in the center. Sanding removes stock. If the half lap joints are cut first and then sanded, a sloppy, ill-fitting joint can result.

Lay out the arches first, but do not cut them just yet. By laying out the arches now, you know what the finished piece will look like and you won't make the notches too deep (see Fig. 4).

Cut the notches in the upper rails first. I used a band saw lo accomplish this because the dado head won't reach all the way to the bottom on the lower rail. If the top surfaces of the two rails are Hush when they are mated, you can cut and sand the arches. If they aren't, you might have to cut the joints deeper or shim them out so that they fit flush.

Fig. 1. Carefully mark the location for the mortises, then cut them as shown. The "X" denotes the inside edge of the leg.

Fig. 2. The top mortises are laid out at the same time so that they line up with those that are on the bottom. The ends of the legs were cut longer than necessary, the mortises were cut, and then excess length was removed. This left the open mortise that formed the female portion of the bridle joint.

Fig. 3. Making the cheek cuts on the tenon.

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