Metal priming before powder coating

The main purpose of powder coating is the durability, aesthetics and anti-corrosion properties of metal products. But in order to really get a high-quality coating, you need to perform the main stages of preparation and painting of metal.

Today in the article we will talk about the primer: what is the metal undercoat for and how to apply it.

Metal priming before powder coating

There is a specially developed undercoat applied before powder paint. It makes the surface smoother and helps better adhesion of the paint to the surface. After all, no matter how good the paint is, the undercoating stage will maximize guarantee of a good adhesion of the polymer paint to the base.

Soil composition

The soil has many components in its composition but two of them can be distinguished:

● powder of reactive metals: zinc flakes (or powder). Zinc oxidizes faster than iron and aluminum, so the base does not rust.

● binders: an epoxy resin that binds and holds all components to the surface, so you get a durable film.

Types of powder soil:

for passive protection – epoxy anti-corrosion compound. A film resistant to mechanical and chemical influences is created. You also get the opportunity to level the surface after sandblasting. Usually used for products that are operated in mild conditions (car wheels, welded structures indoors).

for active protection – epoxy zinc composition. Zinc oxide closes the defect at the edges, thereby preventing further formation of rust. It is used for all metal products and structures that are used in difficult conditions (street flooring, stairs, fences).

Powder coating

First of all, the surface must be cleaned of dirt, rust and old coating. The surface must be completely clean for a good grip.

For example:

Stage 1: sandblasting

Stage 2: phosphating or chromating to eliminate grease (fuel oil, oil) and traces of rust

Stage 3: priming.

Powder primers are usually applied using a spray gun (like powder paint).