Surface preparation

Bristle blasting uses a rotating tool with hardened wire bristles whose tips strike the surface at high speed. The impact removes rust, mill scale and coatings and leaves a textured anchor profile, much like grit blasting — but without loose abrasive media, dust clouds or spent grit to collect.

Grit blasting suits large, open areas where containment and abrasive recovery are practical. Bristle blasting suits spot repairs, welds, edges and sensitive or hard-to-contain areas: there is no abrasive to contain or dispose of, and work can continue next to running operations. Many projects use both.

The coating manufacturer specifies it, often as a range in micrometres. The profile is measured with a comparator (ISO 8503-1/-2) or replica tape (ISO 8503-5). Too little profile weakens adhesion; too much leaves peaks that the coating may not cover.

Flash rust forms quickly on freshly cleaned steel, especially after wet methods. Keep the steel temperature at least 3 °C above the dew point (ISO 8502-4), coat promptly, and where needed use a passivation product that neutralises salts and inhibits flash rust until coating.