It is crucial to do preparations before SMT assembly process during stage of whatever prototype or mass production, which highly determines smooth online manufacturing in avoidance of suspending SMT line to find appropriate components. As you know, efficiency is the lifeline for SMT assembly process. Hence, manufacturers should figure out and fulfill refined process control. Let us look at some crucial preparations.
1. Printed Circuit Board Files (Gerber in particular)
Standard files include 4 layouts at least: PAD, drilling, soldering mask and text screen.
Better in panel
Board edge: 10 mm spacing bottom and top
Mark hole: two holes on right and left with diameter 4 mm and 5 mm spacing boarder.
2. Bill of Material (BOM)
Part model, brand, MFR and reference link
Separate list of SMD and THT components used on top and bottom side
3. Auxiliary data
Board used for oven temperature test
Stencil used for solder paste
SMD components should not be packed in bulk or slice.
Major parts such as IC should not be used before.
Despite all above preparations, human is more than machine in terms of completing SMT assembly process with magnificent quality.