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Tray assembly. Glue each tray's sides together using a simple assembly jig. Rod support. Glue a rod-support

Two spring clamps hold the front tightly against the sides. The thin sides can wedge into each back corner Hold it run long; you'll trim them to final length later. with your thumb for about 10 seconds.

Now it's cimc to glue up the trays— almost. First, epoxy a steel bar into the groove you made earlier in the front of the base iray. Then cut six rod-support wedges. (See Rod-Support Wedge detail, page 49.) The accuracy of the 60* angle in the back of the wedge is critical.

The third trick to tray assembly is the jig I use to glue up each tray. (Sec photo, above.) To crcatc the jig, simply make a triangular 60° cutout in a piccc of in. plywood, melaminc-coarcd particlcboard, or MDF. This 60* angle must be precise. I drilled a ^g-in.-dia. hole centered on the peak of the cutout to allow for glue squeeze-out during glue-up. Make each side of the cutout at least 7 in. long. Glue the cutout piece to a hardboard base.

To assemble a tray, first spread glue on the two 30° ends of the sides and fit them together against the jig's 60* angle. Then apply glue on the 60* ends of the front, and press it into placc between the two sides. Keep everything together with a couple of spring clamps, as shown in the photo above. A thin spacer under the clamps keeps clamping pressure near the centcrline of the front. You'll have to use a larger spaccr for the base tray.

When the glue sets, while the tray is still damped in the assembly jig, glue a rod-support wedge into the tray's back corner. Don't drill the hole yet. Just press each wedge into place with your thumb and hold it for about 10 seconds. (See photo, above right.) In the bottom tray.

glue and stack two wedges together for support. The top of each wedge should be flush with the top edges of its tray.

Plug Holes and Sand

You'll see that the rabbets you cut earlier in the sides are exposed in front. I fill these square holes with little plugs of contrasting wood—usually maple or ebony. (See drawing.) Cut them so that they fit in placc with slight friction, and glue them in — no clamping necessary. Although the plugs arc made of square stock, after you bevel the fronts they'll look like parallelograms. They become a strong decorative element in the finished box. If necessary, trim the plugs flush with the bottom edges of each tray.

Make sure the top and bottom edges of each tray are exactly parallel, so that when you stack the trays they'll all be parallel to each other. I sand the bottom edge of each tray very lightly on a belt sander to get it flat, then feed the trays through a thickness sander to level off the top edges. The extra-long sides of the two smallest trays help stabilize the trays in the thickness sander. If you don't have access to a thickness sander, you can carefully sand the top edges on the belt sander and use calipers to ensure that the top and bottom edges are parallel.

Drill the Rod Holes

One of the keys to the success of this project is accuratcly drilling the holes in the rod-support wedges. First, they have to be perpendicular to the bottom edges of the trays, so setting your drill press table exactly perpendicular to the bit is important. Second, the holes have to be vertically aligned from one tray to the next. To accomplish this, I clamp the assembly jig to the drill press table to position all the trays uniformly for drilling. (Sec left photo, opposite page.)

I use a ^¿-in.-dia. brad-point bit, set the drill speed to 2,100 rpm, and feed the bit slowly to minimize wandering. Drill all the way through the wedges in the four upper trays, but only three-fourths of the way through the base tray.

Insert your 3/|6-in.-dia. brass rod through each hole to check the fit. The rod should slide easily into the hole, and rotate freely. If not, ream the hole lightly with a ^V^-in.-dia. drill bit.

Install the rod in the base and stack all five trays together on the rod. Check once more to make sure the trays are parallel to each other. Then cut the rod to its final length, so that it almost rcachcs the top of the hole in the lid.

Top It Off

Make a V^-in.-thick top panel out of solid wood, using the top tray as a template. It's okay to make the panel slightly oversize and trim it flush later. Glue it down to the rim of the top, and tape it in place to keep it from shifting while you clamp it with small C-clamps. Use soft clamping pads or thick cardboard to avoid marring the wood.

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