Which instrument is used to determine the proper thickness of paint for spraying?

• A. Viscosimeter
• B. Hydrometer
• C. Gage
• D. Caliper

Answer: (A)

Viscosity controls how paint flows and atomizes in a spray. The instrument used to determine how thick the paint is for spraying is a viscosimeter, which measures viscosity—the resistance of the liquid to flow. In practice, painters use a viscosity cup or similar viscometer to verify the paint’s flow time and ensure it falls within the spray equipment’s recommended range. When viscosity is too high, atomization suffers, leading to poor spray, runs, and uneven film; when it’s too low, you get excessive spraying and loss of control. Other tools listed measure different properties: a hydrometer gauges density, a caliper measures dimensions, and a general gauge isn’t specific to liquid viscosity.