Exploded Views and Parts Lists

Exploded Views and Parts Lists

An exploded view separates an assembly's components along their axes of assembly, showing how the product goes together. It is the standard illustration for maintenance manuals and flat-pack instructions.

The rules:

• Components are separated along the line on which they actually assemble — usually the shaft or bolt axis. Moving a part sideways off its axis makes the view misleading.
• Centre lines run through the separated components, showing the assembly path.
• Spacing is chosen for clarity, not to scale — the gaps are not dimensions.
• Each component carries a balloon with its item number, keyed to the parts list.

The parts list tabulates item number, description, quantity and material, and is normally placed above the title block, reading upward.

Worked example. A bolt, washer, bracket and nut exploded along the bolt's axis show the assembly order unambiguously: the sequence along the line is the order of assembly. Explode them off-axis and that information is destroyed.

Core checkpoint: Separate along the assembly axis, and let the sequence along that axis carry the assembly order.