BUFFING WITH 1-2-4 ROLL POLISHING MACHINE
Buffing with these machines is an industrial process managed by professional users. For best results two pastes are generally used (first an abrasive paste then a polishing paste) but a good result can also be achieved by using just one wax, usually with medium-grain properties since it has to be abrasive and polishing at the same time. It all depends on the nature of the paint and the abrasive paper used before passing the paste. These automatic polishing machines need one paste at a time for about 30-40 complete (return) go and forward passes. The polishing paste is spread by the help of a brush on the various parts of the surface requiring polishing after having first been diluted (by 10-20% in volume maximum). There is no a fixed number of passes, each operator must decide on the number required drawing on his experience and the equipment available.
Picture 3 - Single roller automatic buffing machine Sanding is always carried out by crossing the movement of the abrasive paper at right-angles and using sand papers of increasing finesse until 600-800 grain (for polyester) or 800-1000 grain (for polyurethane). The rougher is the paper you use during the last stage of sanding, the more abrasive the paste must be during the first passes. It is always worthy bearing in mind that the quality and performance of the different types of abrasive paper available on the market can very different. The pressure of the rollers must be checked constantly to ensure that the temperature of the surface to be polished does not exceed 40 °C (104 °F). When using a single-roll polishing machine (picture 3) the operator needs more time to get the required level of gloss than with a twin-roll polishing machine. You can easily find on the market polishing machines with four crossed rollers recomended for high productivity (picture 4). |