If the same machined product can reduce the number of times it gets off the machine, the consistency of product quality will be better, and it can also reduce the loss of manual operation. Every time there is an additional process in the product, there may be subtle differences in the process of changing processes, and the accumulation of these subtle differences will cause greater errors. Therefore, reducing the number of machine off, allowing the machine parts to be processed in as few processes as possible, and allowing the machine parts to be less or not off the machine can better ensure the consistency of the product. The same is to process a special-shaped foam lining, if you need to get off the machine frequently to replace the processing surface, then there will be modeling loss due to operation errors in the middle, and at the same time, there may be different effects between different linings due to multiple placements. Therefore, if we want to improve the quality of the lining, we must start to think before processing, so that a lining can be processed at one time as much as possible, or minimize the number of times it gets on and off the machine.