Not all paints are thesame, specifically, there are special mixtures totally free of solvents andthermo-hardening characteristics, which are often used to coat some small ormedium-sized metal objects, to prevent this material from ruining, or for asimple aesthetic purpose. When we talk about these types of paints, werefer to powder paints.
It should be specified that the mixtures of this type, based on organic compounds and resins, can be applied to metal surfaces in different ways, that is why today we will see a complete guide not only on specific paints of this type, but also on painting techniques to powder. You can visit powder coating gallery here.
Powder coating is a particular technique that allows the application of paints on the surfaces of metal objects. In fact, through the application of specific types of paints, the object obtains a coating composed of a film of organic character, which adheres completely to its surface and which has a dual purpose, on the one hand protecting the metal from the aggression of external agents and therefore damage in the medium to long term, on the other hand give it a more pleasant appearance and therefore in this case the purpose is purely aesthetic or design. As it turns out to be obvious that it is, the powder painting is so called because it uses a specific type of paint, in a solid state and therefore without the presence of any type of solvent, the paint powder is always organic and contains all the other classic elements of this compound, including pigments, resins and sometimes also various types of additives. In practice, the only real difference compared to common paints is the total lack of solvent.
How to Make Powder Coating
There are several ways to do powder coating, many of which are obviously reserved for professionals, as they often need specific equipment and environments. So let’s start from the first method that allows you to apply powder paint to metal objects, it is called fluid bed painting, and it happens in a rather particular way. In this case, in fact, it is the metal object to be heated and to be brought to a high temperature, then, on the hot surface of the object, powder paint is fired by compressed air, which immediately adheres to the metal, creating a real fluid painting bed. Obviously, to realize this powder painting technique, an environment to saturate with suspended powders is needed.
The second type of technique for applying powder paint is electrostatic spray painting. In this case a nebulizing spray gun is used which, while throwing dust on the metal surface, adds an electrostatic charge that naturally makes it adhere to the object. This is the classic method used for example in workshops, but also in DIY.
The third and last way to apply powder paint is through the flame painting technique. In this case the powder is fired by a jet of compressed air, but in the presence of a flame generated thanks to the propane, which overheats the powders liquefying them and subsequently making them harden due to contact with the zero-load metal. As it turns out obvious, this technique is exploited exclusively for the thermo-plastic type powder paints.
Advantages and Disadvantages of Powder Coating
Powder coating is a technique with numerous advantages, but it also has some contraindications. Wanting to start from the advantages, it must first be emphasized that this technique leads to a very minimal dispersion of paint, about 2%, and in any case the powders that fall without adhering are always recoverable and reusable. Then, it must also be said that they are definitely less harmful than liquid paints, as they are totally free of solvents, and therefore of highly polluting substances. Finally, the resistance provided by powder coating is truly remarkable.
As for the few cons, it must be specified that to apply powder paint, industrial tools and equipment and temperatures often higher than 200 degrees are required.