Excessive use of hammer and dolly will often ____ the metal

• A. Crack
• B. Warp
• C. Stretch
• D. Harden

Answer: (C)

When you hammer and back with a dolly, you’re forcing the metal to flow and deform plastically. Repeated blows in one area push the material to spread, which thins and lengthens that section. That change in dimensions—stretching—is the typical result of overworking the panel with hammer and dolly. Cracking would be a failure mode that can happen if the metal is overstressed or brittle, but the immediate dimensional change from excessive hammering is stretching. Warping describes curvature and uneven distortion, not a simple elongation, and hardening is a material property change that can occur with cold work but isn’t the primary dimensional outcome in this scenario. To avoid overstretching, work gradually and back with controlled technique, using shrinking methods as needed to maintain correct shape.