Zinc-containing protective primer – types and application

Anticorrosive coating of a car can be based on different technologies, so we will give a brief overview of the methods of applying this anticorrosive coating.

Liquid zinc for cars – anti-corrosive metal coating

Zinc protective primer is available in several versions: primer in cans (requires dilution with solvent and sometimes – the addition of hardener), zinc paint in spray cans (ready for application after shaking), zinc primer in car markers for processing small areas in places of paint chips or scratches on the car.

Cold galvanizing a car always takes place on a cleaned and degreased metal surface. Applying zinc to the body or individual parts of the car is also possible on surfaces already affected by rust.

If cold galvanizing is

• If a rusty surface is applied, the loose rust must be removed mechanically (with sandpaper, grinding wheels, wire brush), the surface must be cleaned and degreased with solvent;
• a new metal part – it must be washed with a cleaning agent and the surface degreased;
• an already painted part – old paint is removed, the surface to be painted is dusted, washed and degreased.

Application of zinc on the bodywork – preparation

Zinc-based automotive primer is available in cans or as zinc paint in spray cans. In either case, the manufacturer's instructions should be followed. Liquid zinc for automotive in cans is usually ready to apply by brush, roller, or dipping. If you plan to apply the zinc by spraying (using a spray gun), it should be diluted with solvent (use the solvent recommended by the manufacturer of the purchased anti-corrosive primer).

Zinc paint in spray cans – ready for immediate use after shaking the can (2-3 minutes). If you're doing the cold galvanizing yourself, reviews confirm that zinc in spray cans is particularly easy and convenient to use. For example, Newton zinc primer receives reviews as a low-cost zinc spray. As a more expensive and higher-quality zinc spray, Wurth Zinc (Wurth) is recommended by car owners.

Zinc-based primer for cars – application methods

As already mentioned, the anti-corrosive coating can be applied with a brush, roller, spray gun or by dipping.

Applying the primer with a brush

The primer, which is supplied in a can, is applied with a brush. The brush should be made of natural bristles, clean, and free of dust, oil, or other contaminants. It is applied in sweeping motions, applying 2-3 coats with a drying time of 15-30 minutes between coats. Each subsequent coat dries more slowly. The final coat takes 8-24 hours to dry.

Applying the zinc primer with a roller

Using a roller is convenient when painting a large car part. The roller should be clean and made of a material resistant to organic solvents.

Application by spraying

If the canned anti-corrosion primer is to be applied with a pneumatic or airless spray gun, it must generally be thinned with solvent. The solvent dilution rate should be determined according to the manufacturer's application instructions for the zinc-based primer. The spray gun must be clean, and the surface to be painted must be prepared.

Applying the primer by dipping

If a small part is to be cold-dip galvanized, the zinc-based primer is usually diluted beforehand (usually at a ratio of 15% by weight). Dipping allows for a uniform anti-corrosive treatment of small, yet complex, curved parts with bars and slots. The part should be dipped evenly into the zinc solution and lifted out again. This process is repeated 2-3 times, with a drying time of 15-30 minutes between coats. Each subsequent coat takes slightly longer to dry, with complete drying occurring after 24 hours.

Liquid zinc in aerosol

Liquid zinc in aerosol is very convenient for self-galvanizing of restoration parts of a car, at least reviews confirm that such anti-corrosive primers in spray cans are very popular.

Automotive paint manufacturers offer a wide selection of zinc sprays: Wurth Zinc (Wurth), Berner Zinc Spray, ZINTEC® Zinc-Based Automotive Primer, and Newton Zinc Primer, all of which receive positive reviews from owners of various car brands. On our website, you can check out the features of Thunder Paint's 520ml Professional Zinc Spray . And if only minor paint damage (chips, scratches) needs to be repaired, you can choose a 15- or 30-ml zinc restoration pen from Autocolor7.com.