How to paint and protect new and fresh hot-dipped galvanized steel ?

Painting new galvanized steel requires special surface preparation and the application of products having good adhesion to this type of surface which is generally very smooth.

Products presented

RD-Eco Powerclean

Powerful biodegradable alkaline concentrate composed of anti-flash rust additives for cleaning...

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The problem

Hot-dip galvanizing is an effective process for lastingly protecting steel against corrosion. This process involves soaking the metal in a bath of liquefied zinc at a very high temperature, which forms a thin layer of zinc on its surface. 

After treatment, the metal presents a grey, smooth and shiny appearance, usually covered with fatty oil residue from the galvanizing process. 

This makes painting tricky, especially during the first year. Indeed, outside exposure for at least a year helps to mattify the surface and eliminate residual oils and grease. 

Additionally, it is often required to give galvanized objects a specific color.

The solution

RD Coatings offers a simple, fast and high-performance solution for painting new galvanized steel in record time thanks to RD-Monoguard.

RD-Monoguard is a new generation, water-based, single-component paint, containing very few VOCs (Volatile Organic Components) making it a less dangerous product for the applicator and the environment.

RD-Monoguard is a DTM (Direct-to-Metal) type paint which is applied as a primer and finish coat. It is UV resistant and available in thousands of shades (RAL, NCS, BS, etc.).

System

ProductConsumption Dry film 
1st layerRD-Monoguard0,20 l/m²
220 s/f-g		80 µ
3.2 mils
2nd layerRD-Monoguard0,20 l/m²
220 s/f-g		80 µ
3.2 mils

/!\ Tip
Choose slightly different shades between the first and second coats so you can easily distinguish them from each other during application.

Application conditions and work preparation

Environmental conditions (general requirements) :

• Minimum air and substrate temperatures: 10°C / 50°F for 24 hours.

• Maximum surface temperature: 55°C / 130°F.

• Maximum relative humidity: 90%.

• Surface temperature must be at least 3°C / 5°F above dew point.

• No threat of rain for 3 hours after application

/!\ Notes

• There cannot be condensation on the surface during application and drying. Caution when working at the beginning or end of the season!

• From 15°C / 59°F, working conditions are comfortable and enable higher productivity. 

• If the project is located in a very hot area with very intense sunshine during the day, avoid applying the system when the sun is most intense on the surface, and prefer to work early in the morning, late in the afternoon or in the shade.

Interesting to know !

RD-Monoguard has no overlap window. In other words, if work must be interrupted due to a sudden change in the weather, it can be resumed later without any problem! Just make sure you clean up according to the time elapsed.

Surface preparation

The surface must always be clean, dry, degreased, and free from any contaminants. 

Use RD-Eco PowerClean, a powerful biodegradable alkaline degreaser that is to be diluted by 20% in clean water.

Spray the solution onto the surface to be treated with a low-pressure sprayer and let it react for approximately 15 minutes.

Then rinse with high pressure clean water equipped with a 0° angle rotating nozzle, at a minimum pressure of 200 bar / 2900 psi.

Allow it to dry afterward.

Application material

RD-Monoguard 

Brush, roller or airless.
Airless: opening of nozzle 010 to 012 – pressure 70 to 150 bars / 1000 to 2200 psi.
Airless application is recommended and makes it easier to achieve the recommended thicknesses.

RD-Eco PowerClean

Low-pressure sprayer. Allow to work, then rinse.

Tool cleaning

Clean with clean water only.

Product application

RD-Eco PowerClean

Dilute between 5 and 20% in water, depending on degree of soiling. Spray on and leave for 15 minutes. Then rinse with a high-pressure cleaner.

RD-Monoguard 

Drying time: (20°C – 68°F)
Dry to the touch: +/- 1 hour
Recoverable: +/- 2 hours

Pictures

Renovation of HVAC units at Brussels Airport.

   

Renovation of the Manitowoc Lighthouse on Lake Michigan

VERS. S43-240322