Measure the plywood at 6 feet long and 12 inches wide. Cut with saw. This is the lid. Put aside.
Repeat Step 1 twice for back and front panels of the trough.
Measure two 12-inch by 6-inch sections of plywood. Cut with saw. These are the hopper sides of the trough.
Measure plywood section at 6 feet long and 8 inches wide. Cut and saw. This is the base that will allow 2 inches on the front and back to allow feed to flow down to the trough.
Create the main feed holder box by screwing the pieces from Steps 1 to 3 together.
Measure and cut the trough from the plywood: the base should be 6 feet long by 8 inches wide, the same as the base of the feed box. The front and back of the trough should both be the same: 6 feet long by 4 inches wide.
Saw the edges of the pieces in Step 6 at a 45-degree angle so they meet flush together, creating the trough.
Measure the side panels to fit the shape of the four sides of the trough to close the trough's ends.
Screw the trough together with the pieces from Steps 7 to 9. It should look like an open-topped tetragon, shorter at the bottom than at the top.
Cut four 18-inch lengths of 2-by-4. Screw into the side panels of the feed holder box, extending down to the ground to hold the trough in place as its legs.
Cut a 2-foot length of broomstick. Screw it into the center of the bottom panel of the trough.
Drill a hole centered in the floor panel to pull the broom handle through. Screw into place 8 inches above the trough base.
Measure the location of the articulating joints on each leg 6 inches above ground and screw in.
Measure the joint attachment point on the exterior trough side panels. Screw in.
Screw 5-inch hinges on the interior top panel to sit flush on the top of the feed box.
Dump the feed in and allow the chickens to rock the trough to dump feed in from the holding box.