Matters needing attention for different types of polishing

(1) Matters needing attention in mold sandpaper grinding and oil stone grinding

1) For the surface of the mold with higher hardness, only clean and soft whetstone can be used to polish the tool.

2) When changing the sand number level during grinding, the workpiece and the operator's hands must be cleaned to avoid bringing coarse sand to the next level of finer grinding operations.

3) When carrying out each grinding process, pay more attention to the WeChat public account (NC programming teaching) for more CNC knowledge. The sandpaper should be ground from different 45° directions until the sand grains of the previous level are eliminated, and the sand paper of the previous level should be polished. After the grain has been removed, the sanding time must be extended by an additional 25% before the next finer grit can be transferred.

4) Changing different directions during grinding can avoid unevenness such as waves on the workpiece.

(2) Matters needing attention in diamond grinding and polishing

Diamond grinding and polishing must be carried out with as little pressure as possible, especially when polishing prehardened steel and polishing with fine abrasive pastes. When polishing with 8 000 abrasive paste, the common load is 100~200g/cm2, but it is difficult to maintain the accuracy of this load. To make this easy, make a thin, narrow handle on the wooden strip, or cut a portion of the bamboo strip to make it softer. This helps control the polishing pressure to ensure that the mold surface pressure is not too high. When using diamond grinding and polishing, not only the work surface needs to be clean, but the hands of the worker must also be very clean.

(3) Matters needing attention in plastic mold polishing

The polishing of plastic molds is very different from the surface polishing required in other industries. Strictly speaking, the polishing of plastic molds should be called mirror finishing. It has high requirements not only for polishing itself but also for surface flatness, smoothness and geometric accuracy. For more CNC knowledge, pay attention to the WeChat public account (NC programming teaching). The standard of mirror polishing is divided into 4 levels: AO=Ra0.008 um, A1=Ra0.016 um, A3=Ra0.032 um, A4=Ra0.063 um , Because electrolytic polishing, fluid polishing and other methods are difficult to accurately control the geometric accuracy of parts, and the surface quality of chemical polishing, ultrasonic polishing, magnetic grinding and polishing methods cannot meet the requirements, so the mirror surface processing of precision molds is still mechanical polishing. main.

The matters needing attention in polishing are as follows:

1) When a new mold cavity starts to be processed, the surface of the workpiece should be checked first, and the surface should be cleaned with kerosene, so that the oilstone surface will not be stuck with dirt and lose the cutting function.

2) Grinding rough lines should be carried out in the order of difficulty first and then easy, especially for some difficult-to-grind dead corners, the deeper bottom should be ground first, and finally the side and the large plane.

3) Some workpieces may have multiple pieces assembled together for polishing. First, the rough pattern or fire pattern of a single workpiece should be ground separately, and then all the workpieces should be ground together until smooth.

4) For workpieces with large or side planes, use whetstone to remove rough grains, and then use straight steel sheets for light transmission testing to check whether there is unevenness or undercutting. Difficulty in demolding or strained parts.

5) In order to prevent the mold workpiece from developing upside down or there are some bonding surfaces that need to be protected, it can be pasted with a saw blade or on the edge with sandpaper, so that the ideal protection effect can be obtained.

6) Pull the plane of the grinding mold back and forth, and try to flatten the handle of the oil stone as much as possible, and do not exceed 25°. Because the slope is too large, the force is rushing from the top to the bottom, which will easily lead to a lot of rough lines on the workpiece.

7) If the surface of the workpiece is polished with a copper sheet or a bamboo sheet pressed against the sandpaper, the sandpaper should not be larger than the tool area, otherwise it will grind to the place that should not be ground.

8) Try not to use a grinding machine to repair the parting surface, because the parting surface trimmed by the grinding wheel head is relatively rough and has uneven waves. If necessary, the grinding wheel head must be repaired to a balance of concentricity.

9) The shape of the grinding tool should be close to the surface shape of the mold, so as to ensure that the workpiece is not ground and deformed.

Jiangmen Gude Polishing Equipment Co., Ltd. established in 2010,We are a Polishing materials manufacturer focused on research and develop,produce and sell all kinds of Polishing Compound, buffing wheels, and accessories,After 13 years development,own 2 subsidiary of a factory and our factory has passed ISO9001 quality management system cetification and Midea audit.

We produce and sell polishing compound for metal ,wooden,musical instrument,furniture,Car paint surface etc,And all matching polishing wheels.We continuously optimize the formula to make the product use with better cutting force and faster brightness.

We also produce other polishing waxes and polishing agents, together with Sisal Polishing Wheel and Cotton Polishing Wheel. In addition, we also produce non-woven polishing, turnover wheel, abrasive belt, etc.

Three factroies are more than 10000 square meters,production capacity and delivery time could fully meet customer's request.We provide ODM and OEM for global super markets,importers,agents ,distributors and Amazon retailers.Products with REACH/ROHS certificates and so on.
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