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Mirror Polishing Skills Mirror Polishing is a time-consuming and expensive process, but using the correct method can improve polishing efficiency. First of all, it must be kept clean, polishing must be carried out in a clean and dust-free room, and both the palm and the mold must be thoroughly cleaned. Dust particles with high hardness can damage the surface of the cavity to be completed. Secondly, each mirror polishing stick can only be used for one grade of diamond paste and must be stored in a dust-proof sealed container. Finally, the finer the diamond paste number, the less diluent should be applied. The pressure applied during mirror polishing depends on the hardness of the grinding rod and the thickness of the diamond paste. For the finest 3* and 1 diamond pastes, the pressure applied should only be equivalent to the weight of the grinding rod. If a faster grinding rate is used, a harder tool and a coarser diamond paste can be used. Mirror Polishing should start with corners, edges, and potholes. Sharp corners and edges should be carefully polished to avoid obtuse and rounded edges, and a harder tool should be used. Mirror Polishing processing method
Address the issue of too much grindingThe more grinding, the worse, as the adage goes. Excessive grinding is the main issue that arises in the grinding process. Over-grinding has two effects: the first is the development of “orange peel” and the second is the development of micro-pits on the cavity’s surface. These two types of “over-grinding” have a wide range of phenomena. The low quantity occurs in mechanical grinding, but hand grinding happens infrequently. When processing and grinding them, molds that are subjected to extreme heat, excessive carburization, and excessive pressure and time frequently develop an “orange peel”-like surface. Low-hardness steels are frequently overground because harder steels can resist higher grinding pressures. Most individuals naturally apply more pressure to get faster results if the grinding of the mold cavity is discovered to be unsatisfactory, but the outcome is frequently counterproductive. The solution is to re-grind using a grinding wheel and, as a finishing step, to grind the control surface of the profile. Then gradually raise the sandpaper’s fineness and polish the item. Therefore, while polishing with 10″ or finer diamond paste, you should use a harsher abrasive stick, use less pressure, and attempt to finish in the shortest amount of time. The type of work that requires the most technical expertise is polishing. It is simple to learn but challenging to master. To reach a high professional level, the proper techniques and equipment must be applied. We must gradually move to worldwide standards and learn sophisticated polishing knowledge and technology from outside sources to increase production efficiency. PMicro-pit formation is mostly caused by the following factors: Using too much power or time during Mirror Polishing. Light pressure should be used so that the projecting particles can be ground flat. If the force is too great, however, the softer steel will be ground away, leaving the entire particle exposed. As a result of the force of the grinding, the exposed particles will fall off and leave pits. Re-grinding using a grinding wheel and using rougher-grade sandpaper as the final step in the process are the solutions.  Mirror Polishing example 11.2767 steel mold insert with a polished surface that is a 28mm concave sphere and a depth of 20mm. Hardness: 56–60 HRC. Polishing level: A-2 mirror surface after being polished from EDM grain (CHARMILLES#33). Polishing process and skills1. Use a diamond ring: The maximum speed is 20000r/min, and the reciprocating stroke is 1mm. Slowly grind and polish, and polish from the outside to the inside in a clockwise direction until the center of the cavity (about 2 minutes). Clean the workpiece and check that all fire patterns have been removed. If completed, go to step 2. 2. Use a copper ring: Add 15μ gypsum lubricant to the workpiece. Lightly press the copper grinding wheel to polish along the spherical surface, moving slowly 8mm/s. Clockwise, follow the designated route from outside to inside. Use even force to avoid the uneven depth of grinding lines. After polishing, clean it up, check whether the surface of the cavity has achieved the effect, and go to step 3 after completion (about 5 minutes). 3. Use a plastic ring (PP material): Add 6μ diamond paste lubricant to the workpiece, and repeat the method in step 2. Use force and gentleness. After completion, clean the workpiece, check the effect, and go to step 4 after the effect is achieved (about 3 minutes). 4. Use a cloth rubber ring: Add 3μ diamond paste to the workpiece, press the cloth ring lightly and repeat the second step. After completion, check the roughness of the workpiece. If it does not meet the requirements, go to step 5 (about 5 minutes). 5. Grind by hand with a cloth: The surface of the mold cavity is polished with 1μ diamond paste. The method is shown in the second step (about 3 minutes). The whole process takes about 30 minutes, including cleaning, changing tools, and inspecting the workpiece.  Mirror Polishing example 2Polishing objects: The surface size of the Injection mold cavity is 100mmx150mmx20mm, the hardness is 48~52HRC, the bottom corners of the four sides are R3mm, and the four corners are R6.5mm. The machined surface is formed by spark machining. Polishing Requirements: #1 S.P.I. First, clean the oil stains with kerosene, then wipe with alcohol until dry. Use 150″ EDM whetstone, first polish R3mm rounded corners and R6.5mm corners, then polish the large flat surface until there is no fire pattern, turn 320″ whetstone and repeat once, or use 180° sandpaper to polish until there is no 150 whetstone pattern, use 320″ The sandpaper is thrown at 45° or 90° from the previous direction until there are no rough lines, only 320 sandpaper grains, then change to 400″ sandpaper and rotate 45° or 90°, throw away all 320″ sandpaper grains, and then change to 600″, 800″, 1000″, 1200*, 0″, 2/0″, 3/0″ and 4/0″ gold sandpaper, polished until all grain disappears. Then start polishing with diamond paste, first clean the molded parts with kerosene and alcohol, first use 15* diamond paste, and a diameter φlin rotary grinder to polish the large plane, and then use a φ3/8in diameter rotary grinder to polish the four-sided R fillet. The polishing time should not be too long, because the surface of the heating cavity of the part will produce orange peel lines or small pinholes. Do not add too much diamond paste, it is best to form a uniform film on the surface. Note that the speed should be slow, and you can press and polish with a little force. After polishing, wipe the polished surface with a clean paper towel or medical cotton to check for sandpaper grains. If there are no grains, use paper to clean the cavity surface. After cleaning with kerosene and alcohol, use 3, 6″, and 9* diamond paste. Repeat the above. Operation, and finally use 1 diamond paste to wipe the cavity with cotton lightly until it is bright, and the polishing is completed. Time Request:
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