I don't know if you know what pneumatic spray painting is. You may have rarely heard of this term, but when it comes to spray guns, no one who trusts the industry of car spray painting knows it!

Air pressure spray painting refers to the process of using a spray gun as the object to spray through compressed air. Its basic principle is that when a certain pressure of compressed air is sprayed out of the annular hole of the nozzle, a negative pressure is formed in front of the nozzle. Under the negative pressure, car paint is extracted through the hole, and after meeting with compressed air, it is atomized and dispersed into small paint particles, which are applied to the surface of the coated object. The commonly used spray guns and other materials are of pneumatic spray properties.

So when doing pneumatic spraying, if you want to spray high-quality paint film, you should pay attention to the following issues during spraying construction:

1、 Before painting, check the things and work environment first

1. The moisture and grease in the air compressor must be released first.

2. Completely clean the spray painting room, and there should be no accumulation of dust, oil, cotton, or other substances.

3. Check if the ventilation system is functioning properly.

2、 Clean appearance of repair area

The spray surface must be washed clean and dry with water; Degreasing agents should be used to degrease oils, waxes, etc.

3、 Using high-quality diluents

The solubility of each paint thinner is different; By using matching diluents and the correct ratio, paint can play a significant role.

4、 The ratio should be correct

Varnish, curing agent, and diluent should be equipped strictly in accordance with the manufacturer's product technical guidelines, and incorrect proportions will affect the effectiveness of the paint.

5、 Mix evenly and ripen for 5-10 minutes

Regardless of the type of paint and manufacturer, it is important to mix evenly, especially for metallic paint. For two component paint, after preparation, let it stand for 5-10 minutes (referred to as the curing time) to allow the resin in the paint to undergo a certain degree of chemical reaction with the curing agent before application, in order to ensure the construction quality and the performance of the paint film.

6、 The air pressure should be appropriate

Under normal circumstances, the air pressure is set between 2.5MPa and 5MPa. Maintaining a spraying pressure of 2.5-3.5MPa is an aspiration, especially when spraying metal paint. The size of the air pressure is closely related to the amount and color of the paint produced. An increase in air pressure will cause silver powder to settle below, making the color lighter; A decrease in air pressure will cause the silver powder to float on top, darkening the color and reducing the glossiness. When spraying glossy topcoat, the air pressure can be slightly lower (2.5-3.5MPa) during the first spray, and higher (3.5MPa-5MPa) during the second spray to achieve brightness. Spraying pressure that is too high or too low can affect the spraying effect.

7、 Correct spraying method

Maintain a distance of 15~3cm between the nozzle of the spray gun and the repaired surface. Adjust the width (chord length) of the spray fan surface to 15-25cm based on the size of the repaired area, with a spraying distance of 5~10min each time, leaving ample drying time.

8、 Pay attention to equipping personal protective equipment

When spraying, it is necessary to wear protective equipment such as protective clothing, goggles, etc. to avoid personal injury.

Article source: Qingyuan Automotive Repair Paint http://www.jinliangxincai.com/