This is usually the case for industrial maintenance and marine painting, structural steelwork, touch up work on coil coated surfaces and vehicle maintenance and repair work.
Acidic pre-treatment such as T-wash or mordant solution are unsuitable where partial weathering has occurred.
Sweep blasting can damage irreparably the galvanized layer on vulnerable edges and corners.
The usual polyvinyl butyral/phosphoric acid based wash primers and the modified short oil alkyd or epoxy ester primers do not normally ensure the expected adhesion improvement they offer on steel and other non ferrous metals.
The technical reasons for these failures are well known:
Surface: hot-dip or electro galvanised steel, aluminium, copper, bronze, stainless steel
All types of solvent based paints can be applied on top of ACTAN®GS. Alkyd paints are not recommended on zinc.
"In order to obtain good adhesion on non-ferrous substrates you must use Actan GS as a primer"
"We are coating galvanised steel purlins for the new tollbooth canopy and spray applying the Actan GS.” . Read more
"Based on the findings of twelve month field trial, it is clear that a recommendation can be made to the Environment Agency, that the repainting of the pipeline systems in the service tunnels can be carried out using ACTAN GS". Read more