Assembly Drawings

Features of an assembly drawing

Dimensions

Detailed dimensions required for manufacture are excluded from assembly drawings. But overall dimensions of the assembled object are usually indicated.

If the spatial relationship between parts if important for the product to function correctly then these should also be indicated on the drawing. For example idicating the maximum and minimum clearance between two parts.

Internal Parts

If there are internal assemblies, sectional views should be used.

Parts list

Each part is given a unique number, indicated on the drawing by a circle with the number in it and a leader line pointing to the part. The leader line terminates in an arrow if the line touches the edge of the component, or in a circle if the line terminates inside the part.

A table of parts should be added to the drawing to identify each part, an example of a parts list is shown below:

The first three items; Item No., Description, and Quantity should be completed for every distint part on your drawing. (i.e. the number of duplicate parts are recorded in the quantity). The material is used for components that are being made within the company. The Remarks column is useful for specifying a manufacturers part number when using bough-in parts.