This paper considers the placement of components onto printed circuit boards (PCB's) using surface mount technology. Multiple automatic placement machines, a variety of PCB types and a large volume for each PCB type characterise the environment studied. The problem addressed is the one of allocating and arranging the components on several placement machines, organised into one or several assembly lines, while considering a different assembly time if components are located at different feeder locations. The one assembly line problem is equivalent to balancing a multi-model assembly line where models are assembled in small batches without component rearrangement between model changes. The objective is to minimise the weighted sum of each assembly PCB cycle time, which is defined as the maximum time a PCB has to spend on each machine. We solve this problem with Lagrangian relaxation techniques. Industrial case study results are presented. We also compare the global performance of five placement machines if they are organised as a single assembly line or broken down into two or more assembly lines.