Photo 12- Cutting a rabbet on the lower
edge of the bottom to leave a lip that will fit in the groove in the
Dry assemble the sides and measure the space inside. Add 3/8" to each of these dimensions, and use those figures to cut the bottom to size. Next put a rabbet on the lower edge of the bottom, as in photo 12. Make the rabbet 1/4" deep, and adjust its location along the thickness of the edge so that the lip that remains is a loose fit in the groove on the sides.
To make splines to fit the grooves in the corners, first rip out thin pieces at the table saw, the thickness of which fits the grooves snugly. Next use a saw and a chisel to cut out small triangles to fit in the joints, as in photo 13. Make the splines such that the grain of the splines runs perpendicular to the line of the miters, not parallel to it.
Photo 13B- Blowup photo of the joint.
Custom fit the splines to fit in the grooves.
So that there is as much room for the splines in the corners as possible, cut off the corners of the bottom as in photo 14. With those out of the way, you can make the splines wider for a stronger joint.
Photo 14- You'll need to chop off the
corners of the bottom to make way for the splines. Rub a little wax on the
corners after they are cut and you have dry fitted the tray, to be sure
that the glue will not grab the bottom corners. The bottom needs to
be able to move with moisture variations, so can't be glued in place.
Dry fit each of the joints to be sure that the splines are not so large that they prevent the joint from coming together, and trim them as necessary. Glue up the tray as in photo 15. Don't use metal clamps- use thin nylon string. Bar clamps will dent the lower edge of the sides, and you can't place them onto the curve of the sides to close up the joints at the top. By wrapping string around the piece as shown, the tops of the joints will come together. More loops equals more pressure, but you only need enough to make the joints meet.
Photo 15- Nylon string is slightly
elastic and so stretches enough to provide some pressure for pulling
together parts like this. Several wrappings should be enough to pull the
joints together. After the string is on, shift the joints by hand for best
alignment, then leave it to dry.
Once out of clamps sand the sides smooth and round the joints a bit. A wipe-on oil finish looks very nice on a small article like this, but doesn't provide much protection against moisture. If you plan to get the tray wet with a lot of bubbly, use a satin polyurethane varnish to protect it well.