Sagging and Running

Problem Description:

Sagging or running in furniture painting occurs when paint moves downward on the surface without proper leveling, especially on vertical surfaces, due to gravity and poor adhesion.

Possible Causes:

• Viscosity Issues: Too low viscosity causes running; too high viscosity results in sagging.
• Drying Speed: Slow-drying paints may not resist gravity, leading to sagging.
• Environmental Conditions: Low temperature can slow drying, increasing the likelihood of runs and sags.

Solutions and Precautions:

• Viscosity Control: Maintain proper paint viscosity (e.g., 13-16 seconds Din-Cup4 at 2.5–3 bar).
• Manage Drying Time: Allow adequate drying time between coats.
• Proper Application Techniques: Apply thin, even coats using the correct brush, roller, or spray gun.
• Control Environment: Monitor temperature and humidity; ideal conditions are 20°C and 45–60% relative humidity.

These measures prevent sagging and running, ensuring high-quality finishes.