Paint preparation

The undercoating, due to its thickness ensures that the coats below are properly insulated and eliminates any imperfections of the layer beneath.

The best results are obtained by applying the undercoat in a spray booth remembering to wipe the affected areas with a Tack-rag before beginning application.

The undercoat should be prepared and applied as specified in the painting schedule.

At this point it is advisable to spray a light coating of enamel (spy coat) which will show up any imperfections. Allow the enamel to dry for the prescribed time and then dry or wet sand either manually or with a sander using the prescribed abrasive paper.

Removal of the spy coat shows up any imperfections, and levels the undercoat in preparation for enamelling. Clean the area thoroughly with compressed air to eliminate any traces of moisture or dust.

It is also advisable to clean the area with silicone-proof solvent and then dry with compressed air. Finally, rub the area with a Tack-rag.

PAINT PREPARATION

Mix the catalyst and thinner following the manufacturers recommendations.

PAINT APPLICATION

The required colour may be prepared by mixing the basic colours in the ratio indicated by the applicable colour formula. The enamels obtained in this way do not have the same viscosity values suitable for application and should therefore be mixed with a catalyst and thinned to the proportions indicated by the manufacturer, using a rod-scale.

It is extremely important that the enamel is thinned correctly in order to avoid defects (running, pin punctures etc).

Before application, check that the colour of the prepared enamel corresponds exactly to the colour of the vehicle. For this purpose the operator should apply the prepared product to a sample of sheet metal using the same procedure which will be used for painting the vehicle. The paint sample should then be compared with one or more areas of the car body and any differences in colour should be corrected by adding the base components.

Once the correct colour has been obtained, and before painting the vehicle, the operator should check that the affected area is perfectly dry and free from grease or dust. Surfaces ready for spraying should never be touched by hand.

In addition to these precautions, some environmental conditions, temperature and humidity for example, may influence the final outcome.

An environmental temperature which is too high will cause the thinner to evaporate too quickly; this begins the moment the paint is emitted from the spray gun, and will therefore prevent the paint from forming a uniform coat which will in turn influence the degree of luster.

High environmental humidity on the other hand prevents the thinner from evaporating and results in the thinner drying (increasing the risk of straining).

Each pass of paint should overlap the previous one by half its width.

Application of the paint is usually carried out by successive applications with adequate intervals being left between coats to allow drying.

Metallic colours may vary in appearance depending on the dispersion of aluminium particles on the surface. Metallic colours can be lightened or darkened by drier or more humid application; by applying drier coats, the flakes of aluminium are more uniformly spread over the thickness of the layer of paint, reflecting more light and rendering the colour apparently lighter.

Allow the paint to dry in strict accordance with the manufacturer's instructions.