A Simple Method for Determining the wet film thickness

Film thickness measurement plays an essential part in the use and testing of paints and coating materials. The film
thickness is a decisive factor in determining appearance, protective qualities and durability.
A film which is too thin will afford inadequate protection and reduced hiding power. For this reason, technical
specifications stipulate minimum film thicknesses and regular controls must be carried out to ensure that these
values are consistent.
On the other hand, an excessively thick film is the result of using too much coating material, causing costs to increase
accordingly. Furthermore, thicker coatings do not always mean an improvement in properties: for example, they
have an adverse affect on drying time. The physical and mechanical properties of a coating are
directly dependent on the film thickness. If meaningful testing is to be conducted, the film thickness must
therefore be uniform.
Wet film thickness gauges are used to check freshly applied coatings and can also be used to calculate the
resulting dry film thickness. If deviations from the specified value are detected, corrective measures can be
taken immediately.

Standards:

• EN ISO 2808
• ASTM D 1212