On the workpieces cut in the previous two stages, preparatory operations are performed for the next stages such as deburring, chamfering, etc., and if possible some machining operations that would be more difficult to carry out later, such as drilling, tapping, milling, turning, etc., are already performed.

The previously prepared parts are delivered to the assembly station, where they are juxtaposed on top of each other, using measuring tools, geometric stops and/or where possible assembly jigs.
Once in place, they are fastened together using welding points or other appropriate fasteners until the entire part, or a subassembly of it, is composed.