Painting with electrified paint has so far been quite an expensive undertaking and the domain of only the most specialised car workshops and paint shops. However, recently, the paint industry has grown enormously, which has resulted in a drop in prices and an increase in the availability of specialised powder coating equipment. Nowadays, almost every slightly more dedicated DIY enthusiast and home-grown refinisher can use this technology as long as they have enough time and knowledge of powder coating. So what kind of powder coating equipment should you buy to start with?
What is powder coating?
Powder coating is an innovative method in varnishing, but if we learn the basic information and acquire the appropriate quality equipment, it will not turn out to be as complicated as it seems at first glance. But first of all, what is powder coating all about?
Well, in the process of powder coating, paint particles in the form of powder are used, which are then electrified with a special painting tool, which is a powder coating gun, and sprayed on metal, conductive, or wooden surfaces. Loading and application of the first layer of the coating takes place due to electrokinetic spraying, i.e. triboelectrification, commonly known as “tribe”, or possibly electrostatic, sometimes referred to as “crown”. The crown method is mainly used in the case of painting metal because the paint adheres due to electrostatic phenomena. In the case of other non-conductive materials, the tribe method is used, where no voltage is used.
The next step is to harden the paint surface. To do this, it has to be subjected to a high temperature, which initially melts the layer and then dries it out. A specialised powder coating furnace is required for these purposes.
What tools are necessary for powder coating?
As we have noticed from reading the previous paragraph, even at the beginning of our adventure with this coating method, we will need appropriate equipment for powder coating. So let’s take a closer look at it.
There are two basic types of powder coating plants: automatic and manual. Automatic, as the name suggests, is characterised by the fact that a specialised machine automatically applies paint in the spray booth. Full automation of this process makes it ideal for the serial painting of many items. This is due to the low cost-effectiveness of this method—in the case of frequent colour changes, the costs may be too high, and thus it becomes unprofitable. Manual powder paint shops are equipped with an applicator with which the paint is applied with a spray gun.
Applicator and powder coating gun
The basic tools in the powder coating process are an appropriate applicator and a powder coating gun. The operation of the powder applicator in the tribe method is based on supplying the paint in the form of powder through the mixing chamber to the charging tube. In this tube, the powder paint is set in motion, then the powder is accelerated and swirled using compressed air. The end of this process is as follows: through the aforementioned charging tube, the paint acquires an electric charge as a result of the friction process; such charged paint particles are blown out, and finally, they are attracted to the grounded objects.
In the case of the voltage applicator technology (crown), an electrostatic field is created between the element and the gun thanks to the high-voltage cascade integrated into the spray gun. Due to the influence of ionised air, powder paint receives a negative electric charge (about the grounded detail), thanks to which it sticks to the element according to the forces of the electrostatic field. These applicators are most often used for metal surfaces because their operation is based on the phenomenon of electrostatics, which would not be possible with other materials.
The powder coating gun is the most important element of this process, so it is worth investing in a suitable, proven model.
Powder coating oven
The purpose of the powder paint polymerization furnaces is the annealing and firing of elements covered with powder varnish. Heating takes place by continuous air circulation caused by the operation of the fan assembly. During the annealing process, the paint for powder coating melts and a homogeneous paint structure is formed on the surface of the object with adequate adhesion to the powder-coated object.
Stable temperature values and a wide range of adjustments while melting the powder make the furnace useful for any type of powder paint. The powder coating furnace is not heated to extremely high temperatures because the desired height in this process is between 140 and 200 degrees C.
The last component of the powder coating equipment is the painting booth. A powder coating booth is a device for electrostatic coating of objects, which consists, among others, of a filter system, fans, a powder paint recovery system, as well as cleaning filter systems, measuring, control, warning, and electrical devices. Powder coating booths can be made of stainless steel, powder-coated or PVC. As we mentioned at the beginning of the article, there are two basic types of cabins: automatic and manual.
Powder coating shops are most often used in the mass production of various items, both large and small. As powder coating is used in many different industries, cabins are used every day for painting cars, auto parts, decorations, furniture, ships, radiators, and many, many more. So, if you are planning to start your powder coating adventure, now is a great time to start.