The deposited solder paste released to the board is manipulated by opening the size of the aperture, and the thickness of the SMT stencil is made out of stainless steel. Excessive paste will cause problems for connectivity and bridging, whereas less paste will compromise the strength of the soldering and joints.

The thickness of an SMT stencil varies with the device for which it is being used. 0.020” pitch small outline integrated circuits (SOICs) can work better with a stencil giving a thin solder paste, whereas thick solder paste works best with 0.050” pitch SOICs. The thickness of the paste stencil for solder ranges from 0.001” to 0.003”. The normal thickness for most of the PCB boards is generally between 0.004” and 0.007”.

How to clean an SMT Stencil SMT stencils are generally cleaned with professional cleaning equipment. Presently, the mainstream of the market is the smart stencil cleaning machine, which is aimed at the electronic industry SMT stencil, copper stencil, wire stencil, microporous stencil, and wafer trays. For the cleaning of similar stencils, the equipment uses compressed air as energy, does not require electricity, and is not a fire hazard.
It adopts a human design and one-button operation, which helps complete cleaning and drying tasks; it utilizes high performance automatic operation of air pressure.