When attaching a back panel to a cabinet, which practice helps prevent racking and keeps the box square?

• A. Install with a single nail at top corner
• B. Use no glue
• C. Pre-drill and place fasteners evenly along the perimeter with glue
• D. Install only on one side

Answer: (C)

A back panel keeps a cabinet square by tying the sides together so they move as a unit rather than independently. When you pre-drill and drive fasteners evenly along the entire perimeter, you create a continuous, distributed hold that pulls the sides toward the back and resists twisting or racking. Adding glue helps fuse the panel to the frame, turning the assembly into a stiff, one-piece box that resists shear and movement under load or transport.

Choosing only a single point at the corner or mounting without glue allows the box to flex or shift because the forces aren’t shared around the perimeter, and mounting on only one side provides little resistance to racking. Placing fasteners evenly with glue around the perimeter gives the cabinet true, square edges and a rigid structure.