The Mark graphic on the laser stencil is used by the automatic printing machine to calibrate the PCB reference before printing each PCB, so the semi-automatic printing machine does not need to make the Mark graphic on the patch stencil;

The automatic printing machine must make Mark graphics. As for which side of the SMT stencil is placed, it should be determined according to the specific structure of the printing machine (the position of the camera). Generally, the Mark graphics are not engraved through, or the black glue is sealed after engraving.