What is the process of polishing plastic molds?
In order to allow the plastic parts to be demolded smoothly during production, and the surface is shiny, the plastic molds are generally polished. In order to achieve perfect polishing results, in addition to the need to prepare high-quality oil stone, sandpaper and diamond paste, it also needs to be polished in strict accordance with the strict process. The following is the process of plastic mold polishing, mainly rough polishing, semi-fine The three steps of throwing and polishing.
Crude stone, sandpaper, diamond paste
the process of polishing plastic molds
Method / step
1,When rough throwing, it is mainly polished with relatively coarse oil stone. The purpose of this is to remove the traces left on the mold surface during machining or EDM. The order of use of oil stone is generally #200 ~ #320 ~ # 400 ~ #600 ~ #800 ~ #1000. Many opportunistic mold polishers have chosen to start at #400 in order to save time, which does not completely remove the traces of the surface, but requires more time for rework.the stone polishing method is the most important and difficult work. According to the different specifications of the processed products, cross-grinding is performed at an angular balance of about 70 degrees. The ideal round trip range is approximately 40 mm to 70 mm. The oil stone work will also vary depending on the material of the processed product.
2,Semi-finishing is mainly to use sandpaper to polish, in order to remove the traces left on the surface of the mold during rough polishing. The order of use of sandpaper is basically the same as that of oilstone - first coarse and then fine, the number of sandpaper is: #400 ~ #600 ~ #800 ~ #1000 ~ #1200 ~ #1500.The focus of sandpaper polishing. the sandpaper is ground with a harder wood bar at an angle of about 70 degrees like the oil stone work, and the sandpaper is polished about 10 to 15 times. If the grinding time is too long, the grinding force of the sandpaper will be reduced, which will result in unevenness of the machined surface (this is one of the reasons for the orange peel).
3,Fine polishing mainly uses diamond polishing paste. If grinding with diamond polishing powder or abrasive paste, the usual grinding order is 9μm (#1800) ~ 6μm (#3000) ~ 3μm (#8000).
A polishing process with an accuracy of more than 1 μm (including 1 μm) can be performed in a clean polishing chamber in the mold shop. For more precise polishing, an absolutely clean space is required. Dust, smoke, dandruff and saliva can all leave high-precision polished surfaces that are obtained after hours of work.
With the wide application of plastic products, such as daily chemical products and beverage packaging containers, the appearance requirements often require the surface of the plastic mold cavity to be mirror polished. The production of optical lenses, laser discs and other molds requires extremely high surface roughness, and therefore the polishing requirements are extremely high. It also allows the mold to have other advantages, such as making the plastic product easy to demold, reducing the production cycle time. Therefore, the process of polishing plastic molds is an important process in the production of plastic molds and plastic injection molding.