The production and testing of parts are based on working drawings of the parts used throughout the process. Product design drawings record the design and specifications of a part and guide manufacturing and quality control.

The creation of these drawings stems directly from the machine's construction. The placement and function of components determine the design of the parts drawing. Therefore, the drawings reflect the engineering design of the entire machine.

The construction of a part drawing requires various elements, including but not limited to:

Title bar with basic identifying information

Collection of graphical symbols indicating materials, surface treatments, tolerances

Required size Specify size, angle, position

Specific technical requirements unique to this part

The term "fit" refers to the elastic relationship between mating parts. It describes the interactions between parts designed to be connected. Therefore, "fit" is crucial for the component's interface.

Basic dimensions provide the starting point for calculations. The ultimate size is obtained by adding the upper and lower deviations to the basic size. Maximum size uses the limit size as its baseline. Finally, the smallest size starts from the largest size. As long as the size falls between the maximum and minimum values, the requirement is met.

Intolerance and fit charts, the zero line passes through the middle. This baseline represents the basic dimensions of the part, anchoring positive/negative deviations.

While national standards may use 8 tolerance classes, the classes contain 20 different levels. The markings on the part determine the correct grade and level of the part.

Note how much deviation from the mean is acceptable. It is important that the space between tolerance levels remains constant. This uniformity must be maintained, otherwise, the linear size fitting code will be used.

Surface roughness is a general term covering various properties of surface texture. Parameters such as Ra help quantify roughness by specifying a numerical value. Therefore, surface roughness can be a stepping stone for manufacturing accuracy and quality control.