The last process of Jianshui purple pottery is grinding, which is a pure work of strength. Of course, to polish well, it also needs very skilled skills. But because this process really tests patience and the spirit of hard work, so hard work often leaves more impression on people.
Let alone the era of cobblestone grinding, which is ten times more difficult than the grinding method I’m going to introduce today. At present, the more common grinding method is to use sand blasting machine to remove the fire skin, and then use towel or other cotton cloth coated with emery, wrap the purple pottery products and grind them together, and then use different mesh number of grinding wheels for grinding.
The efficiency of sand blasting machine with high power and sufficient air pressure is relatively high. Hold the nozzle and spray the fire skin on the surface of purple pottery evenly. Some sandblasting machine power is not high or the air pressure provided by the air compressor is not enough, so it is necessary to step on the sandblasting switch manually. Standing with one foot and controlling the sandblasting switch with the other foot, even those who have been operating for a long time will have their feet ache, let alone those who have just learned to operate.
For purple pottery with regular shape, it is a relatively fast method to polish purple pottery with cotton cloth coated with emery. The color of this method is uniform, and it is not easy to damage the purple pottery. The other function of emery is to grind the lid of the pot. The purple pottery pot and the lid will not be completely sealed when they are just burned out. It is necessary to use the emery to continuously rotate the lid and grind it until it is completely sealed.
What we usually call sub gloss, bright light and other different degrees of grinding effect is determined by the mesh number (thickness) of the grinding wheel. The higher the mesh number, the finer the grinding wheel and the more times of grinding, the brighter the grinding effect will be; the lower the mesh number, the thicker the grinding wheel and the less grinding times, the rougher the grinding effect will be. That’s why the light of the same purple pottery is more expensive than that of the light.
When grinding with grinding wheel, ventilation should be maintained or vacuum cleaner should be installed. When grinding, a large amount of dust will be generated, which will cause harm to human body. At the same time, the force and speed of grinding should be controlled to ensure the grinding effect and avoid injury during grinding on the other hand.