Compound miter joints are commonly used on:

• A. Doors
• B. Crown molding
• C. Tables
• D. Shelving

Answer: (B)

Compound miter joints are cut at angles in two different directions, which is needed whenever a piece sits between two planes that aren’t parallel to each other. Crown molding sits between the wall and the ceiling, so the joint where two pieces meet has to account for both the horizontal corner and the vertical tilt. That requires a bevel cut (tilt) and a miter cut (rotation) on the saw—two angles at once. Doors, tables, and shelving typically use joints that lie in a single plane or rely on straight cuts and standard butt or dado joints, not the two-axis angles of a compound cut. So crown molding is the classic application for compound miter joints.