Large scale machining, not all materials can be fine processed, some materials are too hard, beyond the hardness of the machining parts, it is possible to break the parts, so these materials are not suitable for fine machining, except for the parts made of special materials, or laser cutting.

　　The materials for large-scale machining are divided into two categories: metal materials and non-metal materials.

　　As for metal materials, the hardness of stainless steel is the largest, followed by cast iron, followed by copper, and finally aluminum.

　　The processing of ceramics and plastics is attributed to the processing of non-metallic materials. Stainless steel material for large machining.

　　1. First of all, it is the requirement of material hardness. For some occasions, the higher the material hardness is, the better it is. It is only limited to the hardness requirements of machining parts. The processed materials cannot be too hard. If they are harder than the parts, they cannot be machined.

　　2. Secondly, the material is of moderate hardness, at least one level lower than the hardness of the parts. At the same time, it depends on what the function of the processed parts is to do and the reasonable material selection of the parts.

　　In a word, there are still some requirements for materials in large-scale machining, not all materials are suitable for machining, such as too soft or too hard materials. The former is not necessary for machining, while the latter is not.

　　Therefore, the most basic one is to pay attention to the density of the material before processing. If the density is too large, it is equivalent to the hardness. If the hardness exceeds the hardness of the machine (lathe tool), it cannot be processed. It will not only damage the parts, but also cause danger, such as the tool flying out and hurting people. For large-scale machining, generally speaking, for machining, the material material should be lower than the hardness of the cutter, so that it can be processed.