Question: We build components, and we would like to get your suggestion on which max limit column to follow. I am thinking Assembly Max Contaminant, due to the fact that we strip and tin, and solder connections to our components. We are not using our pots to solder the components to the board. Would that be the correct category to follow for us?
Answer: In the manufacturing of components, you are preparing the components for soldering which is a form of Preconditioning of the component. One of the differences we’ve seen is the physical size of the solder pot and the amount in weight within those solder pots. The assembly Maximum column is for assembly of the components onto and into printed boards, or boards which will be wave soldered and in this category we have to be concerned with the aggregate of various metals, which can be seen in the bottom row of Table 3-1 in J-STD-001.
The column to use for your application is the Preconditioning Maximum column.