What are the differences between standard and non-standard parts of CNC machining?

Standard parts refer to the zero (part) parts, such as threaded parts, keys, pins, rolling bearings and so on, which have been completely standardized in structure, size, drawing, marking and other aspects and are commonly used by professional factories. In a broad sense, it includes standardized fasteners, connectors, transmission parts, seals, hydraulic components, pneumatic components, bearings, springs and other mechanical parts. Narrow sense includes standard fastener only. Domestic commonly known as standard parts is the abbreviation of standard fastener, is a narrow concept, but can not exclude the existence of a broad concept,. In addition, there are industry standard parts, such as automotive standard parts, mold standard parts, etc., also belong to the broad standard parts
Non-standard parts are mainly parts that the state has not set up strict standard specifications, and other parts that are controlled by the enterprise freely without relevant parameters. There are many kinds of non-standard parts, there is no very standard classification. The general classification is as follows:
Non-standard metal parts:
The customer provides the drawing, the manufacturer USES the equipment to make the corresponding product according to the drawing, usually is the mold majority, the tolerance request, the smoothness is the customer stipulation, does not have the certain pattern. Products from casting to finishing completely need corresponding quality control, the process is complex and variable, the general cost is higher than the standard parts.
Non-metallic non-standard parts:
It is the processing of some nonmetallic materials. Such as plastic, wood, stone, etc., in recent years, the injection molding industry, the development of plastic mold is increasingly sophisticated, curved surface design, programming CNC reference, so that the cost of non-standard processing and tolerance level have been greatly improved.