HMG Knowledge Base
Film Thickness Best Practices
General Advice In Application
HMG Technical Data Sheets indicate a Dry Film Thickness that will be achieved when applying a particular Wet Film Thickness. These values are a guide only and are not to be used as specifications.
The protection and durability of any paint system is related to the total film thickness of the paint applied. Therefore, it is not sufficient to refer to a ‘coat of paint’ and in typical paint specifications (Agreed by the relevant parties) Dry Film Thicknesses should be stated for each coating and the total system.
Great care should be taken to achieve the Dry Film Thickness stated in the specification and to avoid areas of excessively low or high thickness. During application, some variation of film thickness is inevitable, but may be monitored by:
a) Control of Wet Film Thickness during application (Wet Film Thickness combs).
B) Measurement of Dry Film Thickness on completion.
Over the coated area, individual Dry Film Thicknesses of less than 80% or more than 120% are deemed as unacceptable and out of specification.
Advice and best practice can be found in ISO 12944 (1998)