Back-To-Basics: Environmental Considerations For Refinishing

Some refinishing defects are controllable. However, refinishing defects that are influenced by the environment may not be controlled. Let’s take a look at environmental impacts on both solvent-borne and waterborne refinishing processes, like temperature, and humidity.

Temperature affects refinish materials in multiple ways. The first is that if it is too warm, it will accelerate the flash and cure time of the refinish material. This can lead to many refinishing defects, like solvent popping and dry spray, for example.

If the temperature is too cold, it will decelerate the flash and cure time of the refinish material, which can lead to runs and sags.

Humidity can also have an impact on refinishing. When the air is too humid, it slows the evaporation process in both waterborne paint and solvent-borne paints. This may cause poor curing, sagging, puddling (also called water splashing), and solvent popping.

Water splashing occurs in waterborne paint when the humidity is high and the first coat starts dimpling from the overspray of the next coat. It looks similar to rain drops hitting a puddle.

When it’s humid, water molecules in the air get trapped under the refinish coating and may cause blistering or bubbling. Humidity can also greatly affect the ability to cure because of moisture trapped in the coating.

Temperature and humidity can't always be controlled in the repair facility, so it’s important to know what the weather will be like and to plan accordingly. For example, making sure to select proper reducers or hardeners that are compatible with the ambient temperature.

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