Making the Tambour
I’ve saved the most interesting task for last: making the tambour that forms the box’s retracting top. To make stock for the tambour’s slats, resaw enough 11-1⁄2″ long 4/4 boards to make twenty- four 1/2″ wide slats as shown in Figure 10. Plane each of the resawn boards down to 3/16″ thick, then crosscut the boards exactly 113⁄16″ long, making sure all ends are cut square.
Rip the slats to 1/2″ width on the table saw, using a quality blade that leaves nice, clean-cut edges. To save time, I adhesive transfer tape the boards together, and gang cut four slats at a time (Figure 11).
Create a frame for assembling the tambour by nailing or screwing 1/2″ thick scrap strips to a flat piece of 1/2″ or 3/4″ plywood. Make the inside dimensions of the frame 11-3⁄16″ wide by 12″ long. Now set the best 21 of the slats you cut into this frame, with their “good” sides facing down. Add an extra slat, covered with masking tape after the last good slat. Press the tambour tightly together by driving three pairs of small wedges against each other between the last taped slat and the frame (Figure 12).
An 11-1⁄8″ x 11″ piece of lightweight (9-11 oz.) canvas duck fabric makes the flexible back of the tambour. Carefully spread a light, even coating of yellow or white PVA glue onto the slat assembly and press the canvas down onto the slats. Align it with the frame and wipe off any excess glue from around the edges. To set the glue quickly (to keep it from seeping down between the slats), use a household iron on a medium setting (no steam) to heat the canvas (Figure 13). Work the iron over the surface for a minute or so, applying only light pressure and keeping the iron moving at all times. Let the tambour cool for about 10 minutes, then remove the tambour from the frame and bend the joints between all the slats open, to assure they’re not stuck together. Now set the tambour aside overnight, to let the glue fully cure.
The next day, trim back the canvas at the sides of the tambour 3/16″ from the ends of the slats (Figure 14). On the band saw, trim 7/16″ off of both ends of the last slat (at the rear of the tambour), so it can be attached to the drawer. Also reduce the width of the first slat (at the front) to 5/16″ wide using a table saw or jointer. To finish off the tambour, the front slat receives a cap strip, cut to the size and profile.
Glue this strip in place, centering it on the length of the slat (Figure 15). Now sand the entire tambour surface smooth, easing the edges between slats and rounding their ends slightly. Wax the slat ends a little, so that the tambour will slide more easily within the track.
To attach the tambour to the drawer, dry-assemble the box and clamp the sides, bottom and shelf together (Figure 16). Slide the drawer into place and turn the whole thing upside down on the bench.
Slip the tambour into its track with the capped end first (Figure 17). With the drawer held fully closed and the tambour cap tight against the pull strip, press the last trimmed slat against the drawer bottom and drill a pair of small diameter countersunk holes into the edge of the drawer back, spaced about an inch from the ends (Figure 18).
Drive 3/4″ long #6 screws into the countersunk holes, then flip the assembly over and make sure the tambour retracts smoothly when you pull the drawer open.
Assembly and Finishing
After taking the dry assembly apart, glue the bead strip to the shelf, locating it parallel to and 5/16″ back from the shelf’s front edge. Glue the shelf, bottom and sides together, applying just enough glue to coat the biscuits and slots thoroughly. After the glue dries, remove any squeeze-out and sand the entire box, rounding over all edges slightly with sandpaper. You can apply any finish to the box, but an oil finish makes it much easier to finish the tambour slats, so that is my recommendation. Reconnect the tambour and drawer, and your box is ready for use. With any luck, you’ll hear a little “wow” the first time somebody opens it.