We know how important it is to start the assembly process with the correct stencil. Choosing the correct thickness and having your apertures cut to match your manufacturing capabilities and PCB technology is essential to the quality of your end product.
At Precision, we supply various thicknesses and sizes of high-quality stainless-steel laser cut stencils, both framed and framed.
Framed vs Frameless
Framed stencils are permanently mounted in a stencil frame using a mesh border to tightly stretch the stencil foil taut in the frame.
Frameless stencils do not need to be permanently glued in a frame as they are designed to work with stencil tensioning systems. They are significantly less expensive than framed stencils and require less storage space.
The first requirement to consider when requesting stencils is its thickness. It is important to maintain a minimum aspect ratio of 1:5 between the smallest aperture width and stencil thickness, as this will prevent clogging. If the aspect ratio is less than 1:5, solder paste will tend to remain in the opening.
Stencil aperture design is a crucial step in optimising the print process. Here are a few general recommendations:
Discrete components: 10% - 20% aperture reductions to avoid occurrence of solder beads.
Fine pitch components: 5% - 15% aperture reduction to minimize solder balling and bridging.
We can make any necessary aperture adjustments, if required.