When it comes to correct or remove the painting of a vehicle, either totally or partially, the machines polishers are the right tools. Not only do they remove paint damage and defects, such as scratches and swirls, they enhance shine through the final finish.
There are basically two types of polishers electrical:
a) Rotary (or circular) polisher
b) Double action polisher (or orbital)
While the polishers rotating They are the most common and traditional, their handling requires great experience and expertise. In view of this, the double action polishers, which are much simpler and achieve a perfect finish even in the hands of beginners, but their range of features is narrower and they are not available in all countries.
We will now take a closer look at each type of polisher. However, first we are going to briefly describe the parts of this tool. Although the following image shows a polisher rotary, its parts are common with those of the double action polishers. The design can vary according to brands and models, but basically both types contain the same parts.
The fundamental difference between one type and the other is given by the way of rotation of the cap or pad polishing and is the one that gives the name to each machine. Said turn is schematically represented in the Figure 2. In the rotary polishers the pad rotates on its axis describing a circle (hence the name “circular”) and the speed is measured in revolutions per minute. On the contrary, in double action polishers the pad not only rotates in a circular fashion, but it also oscillates (hence the name “double action”: it rotates and oscillates) describing elliptical orbits (hence the name “orbital”) and the velocity is measured in oscillations per minute. These distinctive characteristics give the machines certain peculiarities that we will see below.
a) Rotary polishers
They were the first machines used for polishing vehicle bodywork and are still widely used today. The fact that the pad is in only circular motion allows for a more even distribution of cutting abrasives and thus makes the machine a highly flexible instrument for paint correction. However, it should be borne in mind that circular turning generates a lot of heat and if extreme care is not taken, the paint can easily burn.
As an added bonus, rotary polishers can use pads both foam like wool. The latter have much greater cutting capacity, which is why they must be used with care, but at the same time they make the machine the must-have tool when it comes to completely removing deep scratches.
In addition to being excellent for correcting paint, the rotary polishers they also stand out in the finish. The even distribution of the abrasives thanks to the circular spin determines a sharper finish, especially noticeable in certain types of paints, such as those of dark color.
How to choose a rotary polisher
To choose one rotary polisher Proper proper handling, many factors must be considered, including speed ranges, machine weight, location of switch and controls, general ergonomics, and various specifications. However, to get the best out of the polisher It is important to focus on these three characteristics:
- Speed: preferably variable and in a range of at least 1100-2000 rpm.
- Speed control: preferably electronic
- Ergonomics: it must be comfortable
The variable speed is essential to take advantage of the flexibility of the rotary polisher, and the longer the interval, the better. Lower speeds are useful for finishing and refining; higher speeds are useful for aggressive polishing. The electronic speed control ensures that the pad rotates at a constant speed, regardless of the applied force, and is very useful because it ensures machine predictability and prevents the pad from jamming at slow speeds, which could hamper the finishing operation.
But, fundamentally, the ergonomics of the machine must be comfortable for the user and for this there is no universal law. There are several models of different weight and location of controls. The important thing is to try several polishers and decide the purchase of the one with which the user feels most comfortable.
The variety of pads for rotary polishers it is extremely broad. As already stated, these machines can use both foam and wool pads. It is recommended that beginners not use wool pads, due to the high cutting capacity they offer.
The foam pads for rotary polishers They come in a wide variety of grades and styles. Each type of pad uses different degrees of foam, which affect the roughness and hardness of the pad. This translates into the polishing power the pad will have and affects its ability in the finishing stage. There are pads cut (light, moderate and thick), of polished and of finish (common and fine), each one of a different color depending on the function. It is convenient to choose a wide variety of foam grades, since this way we will have many options for all types of paint imperfections, from difficult swirls and deterioration of components to obtaining a high-gloss finish with a specific polishing product. Therefore, to get started, it is always helpful to purchase a set of pads that contains at least one cutting pad, two polishing pads, and one finishing pad.
When it comes to pad sizes, these range from 3 to 8 inches in diameter. The use of each size depends on the part of the body to work. Large surfaces, for example roofs and hoods, lend themselves to large pads, 6 to 8 inches. For smaller surfaces such as badges, bumpers, trunk / trunk lids, 3-4 inch pads are used.
Finally, the selection of the polishing product It must also be careful and according to the work to be done. Like the pads, there are also liquid or paste products for cutting, polishing and finishing, as well as cleaners, swirl removers and other specific products. Although the offer is very varied, you only need two basic products to get started: a medium-grade polisher and a light-grade polisher. Once the user becomes sufficiently familiar with these products, they can gradually expand into coarse-grade polishers and other specialty products.
The main disadvantage of the rotary polishers It is the high degree of experience that they demand from the operator. In suitable hands they achieve excellent results in a short time, but in inexperienced hands they can end in serious damage to the paint, from the appearance of the classic “holograms” to burns. That is why a good and prolonged practice, added to a lot of patience, is the indispensable preliminary step of every beginner for the profitable handling of this tool.
b) Double action polishers
As we have seen, in the double action polishers the pad describes a circular and elliptical turn, generating much less heat on the paint layer, less aggressiveness in the work, more confidence in the inexperienced operator and, therefore, more time to achieve the correction.
Despite these advantages, there are few providers of double action polishers, at least, among the most popular, and not only do they offer them somewhat more expensive than the rotary polishers, but very few are adapted to the different voltages used around the world, so, with few exceptions, they must be connected to a voltage transformer.
Unlike rotary, double action polishers They only use foam pads, sometimes two overlapping, depending on the manufacturer. The pads are smaller – between 4 and 6 inches in diameter. However, both pads and polishing products are also offered for the various cutting, polishing and finishing operations, so all the recommendations given for the rotary polishers they are also valid in this case.
The double action polishers They are ideal for the hobbyist, with or without experience, and indicated to have in our garage. They are lightweight, very easy to use, they do not leave any type of mark or hologram on the paint of our vehicle and we can trust that whether we know how to use them or not we will not cause any damage to the paint. However, the limited availability, both of the machine itself and its accessories, has not yet made the double action polishers a popular tool. This video shows its benefits.