Attach Top and Bottom Panels

What happens here

Spread wood glue evenly along the top edges of the U-shaped shelf frame and the newly attached back piece. Carefully place one of the 9-inch plywood panels (from Step 3) on top, aligning all edges. Use a rubber mallet to gently tap the panel into place, ensuring a tight fit. Repeat this process for the bottom panel. Secure both panels with clamps, applying just enough pressure to create a strong bond without squeezing out all the glue. Allow sufficient time for the glue to dry completely.

Goal: Apply glue to the top and bottom edges of the assembled shelf frame, then carefully position and secure the 9-inch top and bottom panels. Use a rubber mallet to ensure a snug fit and apply clamps until the glue cures.