德语
Polishing is a very important process in the plastic mold making process. Generally, it is a process of polishing the cavity surface of the mold using oilstone, sandpaper, polishing paste, etc., so that the working surface of the mold can be as bright as a mirror.
Mold polishing can make the surface of the product produced smooth and beautiful. In addition, it can make the product easier to demould from the mold.
The standards for mold mirror polishing processing are divided into four levels:
A0=Ra0.008μm
A1=Ra0.016μm
A3 = ra0.032μm
A4 = RA0.063μm
1. Method of mold polishing
When polishing molds, do not use the finest oil, sandpaper, or grinding polishing paste from the beginning. In this way, the thick textures cannot be thrown away. The polished surface looks very bright, but when the side is shining, the thick textures will appear. Therefore, you must first polish it from coarse oil, sandpaper or grinding polishing paste, then replace it with finer oil, sandpaper or grinding polishing paste for grinding, and finally use the finest polishing paste for polishing.
This seems to be more troublesome and has many processes. In fact, it is not slow. One after another, the thick processing patterns in the front are polished off, and then the following process is carried out, and there is no rework. You can make the finish of the mold meet the requirements by walking down one time.
Generally, the surface of the mold cavity of the machine-processed mold is roughly polished, and the marks of the machine and the tool are polished, then the fine oil stone is polished and removed to achieve the traces. Then the surface of the polished oil stone is polished with fine sandpaper and then polished the surface of the mold cavity with fine sandpaper. Finally, polishing paste or grinding paste is used to perform the final polishing and polishing of the mold cavity surface, and finally achieve the effect of being as bright as a mirror. This is the whole process of polishing a mold.
Of course, if possible, an ultrasonic polishing machine can be used to polish the mold, which will be more efficient and save more effort.
2. Pay attention to the following points when polishing with sandpaper
(1) Polishing with sandpaper requires soft wooden sticks or bamboo sticks. When polishing the round or spherical surface, using a cork rod can better match the curve of the round and spherical surface. The harder wood strips are more suitable for polishing flat surfaces. Trim the ends of the wooden strips so that they can be consistent with the surface shape of the steel parts, which can prevent the sharp angle of the wooden strips (or bamboo strips) from touching the surface of the steel parts and causing deep scratches.
(2) When using different models of sandpaper, the polishing direction should be changed by 45°-90°, so that the stripes shadows left by the previous model of sandpaper can be distinguished. Before changing to different models of sandpaper, you must use 100% pure cotton to dip alcohol and other cleaning liquid to carefully wipe the polishing surface, because a small piece of sand left on the surface will destroy the entire polishing work. This cleaning process is equally important when switching from sandpaper polishing to diamond abrasive paste polishing. All particles and kerosene must be completely cleaned before polishing continues.
(3) In order to avoid scratching and burning the surface of the workpiece, special care must be taken when polishing with #1200 and #1500 sandpaper. Therefore, it is necessary to load a light load and polish the surface by using a two-step polishing method. When polishing with each model of sandpaper, polishing should be done twice in two different directions, turning 45°-90° between the two directions each time.
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