Surface Profile Gauges

Preparing a surface correctly is essential to the long-term performance of any protective coating. Steel and other substrates are typically abrasive-blast cleaned or roughened before painting to create a textured finish known as the surface profile. This profile provides a physical “key” for the coating to grip.

If the surface profile is too shallow, the coating may not bond securely, leading to premature failure. If it is too deep, the peaks can remain under-coated, encouraging rust and requiring additional paint—and extra labour—to achieve full coverage.

Recent research has shown that peak density—the number of peaks per unit area—is just as important as overall peak-to-valley height. A surface with an optimal combination of height and peak density offers the best chance of strong adhesion and long-term corrosion resistance.

Surface profile measurement is also valuable beyond steelwork. It helps verify the texture of non-skid finishes, and it’s a recognised way to assess the Concrete Surface Profile (CSP) before applying floor coatings or overlays.

DFT Instruments supplies a complete range of surface profile gauges to suit every application, from quick visual checks to high-precision electronic measurement, each supplied with calibration certification and full UK support.