1. Design PCB, create punching files, lay copper plates on both sides of the PCB, then polish the copper plates on both sides for CNC drilling, and inspect for defects after polishing and drying.

　　2. Main process through hole: To complete the hole, the hole should be sorted and standardized. After confirming that there are no defects in the hole through water washing, drying, and other procedures, black holes should be made to prepare for copper plating through the hole. Next, through holes should be drilled and dried (to ensure sufficient black space, water washing and drying should be performed twice). After completion, copper plating can be carried out. After copper plating, polishing should be carried out, and the hole should be checked again for defects.

　　3. Production process: apply photosensitive blue oil - dry ink - apply bottom and top line film, and position properly - expose and develop appropriately - wash and dry with water - check for defects in the circuit - tin plating - wash with water - corrosion - tin fading - apply solder mask ink - dry ink - apply solder pad film and position properly - expose appropriately - develop and inspect defects - wash and dry - apply character ink, dry ink - apply character film Appropriate exposure - developing+checking for defects - washing, drying - curing ink.

　　4. Mechanical forming treatment: Cut off excess parts and make a square and standardized PCB board. Next, you can solder electronic components onto the PCB. After soldering the components, they can be powered on for testing and assembled for sale.