The Short Scoop: Introduction to Stencil Printing
Approximately 50% of defects that occur on an SMT assembly line can be attributed to the printing process. Doesn’t it seem odd, then, that instead of focusing on quality and experienced technical support, stencils have become a commodity and are being sold by a broad range of stencil suppliers, sometimes solely on the basis of price? At the same time, we continue to see more challenging requirements for stencil performance, driven by the continuous miniaturization of packages and components. Many different types of stencils are available today from many different suppliers, but not all stencils are created equal. And because the industry operates in a quick-turn, dynamic environment, industry lead-times for delivery, in many cases, are as important as the stencil’s capabilities.
Stencils range from the fairly straight-forward technology of a laser-cut stencil manufactured on some form of stainless steel material, to the high-end full-nickel electroformed stencil, along with many versions and variations in between. Stencil selection depends on the specific technology required for an application.Read the full column here.Editor's Note: This column originally appeared in the May 2013 issue of SMT Magazine.