Simple Analysis of the Polishing Steps of Mold Manufacturers

The polishing in plastic mold processing is very different from the surface polishing required in other industries. Strictly speaking, the polishing of mold manufacturers should be called mirror processing. It not only has high requirements for polishing itself, but also has high standards for surface flatness, smoothness and geometric accuracy. Mold manufacturers generally only need to obtain bright surface for surface polishing.

The standard of mirror processing is divided into four levels. Because it is difficult to accurately control the geometric accuracy of parts by electrolytic polishing, fluid polishing and other methods, and the surface quality of chemical polishing, ultrasonic polishing, magnetic abrasive polishing and other methods cannot meet the requirements, the mirror processing of precision molds is mainly mechanical polishing.

1. Semi fine polishing mainly uses Xieyanshi sandpaper and kerosene.

2. Fine polishing mainly uses diamond grinding paste. If the normal grinding sequence is 9um (# 1800) - 6um (# 3000) - um (8000). 9um diamond abrasive paste and polishing cloth wheel can be used to remove hair like abrasion marks left by # 1200 and # 1500 sandpaper. Then polish with felt and diamond grinding paste in the order of 1um (# 14000) - 1/2um (60000) - 1/4um (# 100000). The polishing process with an accuracy of more than 1um (including 1um) requires a clean space for mold polishing. Dust, smoke, dandruff and saliva may scrap the high-precision polished surface obtained after several hours of work.

3. For the basic procedure of mechanical polishing, in order to obtain high-quality polishing effect, it is important to have high-quality polishing tools and accessories such as oilstone, Xieyanshi sandpaper and abrasive paste. Also important is the polishing working environment, which requires a dust-free workshop. The selection of polishing program depends on the surface condition of the pre processing, such as mechanical processing, electrical discharge machining, grinding, etc.

4. The general process of mechanical polishing is as follows: the surface after rough polishing, fine milling, electric spark, grinding and other processes can be polished with a rotary surface polishing machine or an ultrasonic grinder with a rotational speed of 35000-40000 rpm. The common method is to remove the white spark layer with wheels with a diameter of 3mm and WA # 400. Then hand grinding is carried out, and the strip diamond oilstone is added with kerosene as the lubricant or coolant. The general order of use is # 180 - # 240 - # 400 - # 600 - # 1000.