Stencil is a stainless steel foil screen with SMD pads etched or lasered openings, used for solder paste printing in PCB assembly. Refer to SMD Stencil.
Usage
Squeegee solder paste through the windows, the stencil ensures the solder paste is the right amount on the right position. Then you can place surface mount components on solder paste and put it into a reflow oven.
Type
The tool is a kind of bare stainless steel sheet. It could be in a frame or without a frame. The framework is for automated stencil machines. Non-framework is for hand solder. Usually, the framework is heavier and bigger than non-framework. So the framework is more expensive to ship and might be charged for dimensional weight shipping.
Existing Fiducials
Fiducials are positioning points for automated pick and place machines. The diameter of the fiducials is usually 1mm. We offered three options: none, half lasered and lasered through. Half lasered is a sunk bump, lasered through is a through-hole. Half lasered is for automated stencil machines. Lasered through is for hand solder or semi-automated assembly machine. Please note that if you choose half lasered or lasered through, but there are no fiducials inside, we’ll ignore this option.
Electropolishing
Electropolishing (also known as electrochemical deburring) will remove small burrs, improve the surface quality and provide smooth inside walls for better paste release. This treatment is mainly for IC lead width less than 0.5mm and BGA chips.