Step 1: Solder Paste Printing Solder paste printing is the first step in PCBA processing. We apply solder paste to the area of the printed circuit board where components need to be assembled. This step is accomplished by applying solder paste on the stainless steel template, which corresponds to the circuit board, and the solder paste drips from the holes of the template onto the PCB. 96.5% tin is gray and it contains 3% silver and 0.5% copper. In order to protect the environment, FS Technology uses lead-free solder paste. The... read full review »