A coating thickness gauge (also referred to as a paint meter) is used to measure dry film thickness. Dry film thickness is probably the most critical measurement in the coatings industry because of its impact on the coating process, quality and cost. Dry film thickness measurements can be used to evaluate a coating’s expected life, the product’s appearance and performance, and ensure compliance with a host of International Standards.

Dry film thickness (DFT) can be measured using two methods: destructive thickness measurement, where the coating is cut to the substrate using a cutter; and non-destructive coating thickness measurement, using techniques which do not damage the coating or the substrate such as magnetic, magnetic induction and eddy current thickness measurement methods.

The non-destructive coating thickness measurements can be taken on either magnetic steel surfaces or non-magnetic metal surfaces such as stainless steel or aluminium. Digital coating thickness gauges are ideal to measure coating thickness on metallic substrates. Electromagnetic induction is used for non-magnetic coatings on ferrous substrates such as steel, whilst the eddy current principle is used for non-conductive coatings on non-ferrous metal substrates