What are the factors that lead to the shortage of solder paste in SMT steel mesh?

Most people in the industry know what SMT steel mesh is, but more people in the general public have always thought that SMT steel mesh is a general steel mesh that is usually woven with steel wire. But Xiaobian wants to inform you that SMT stencil is not a general stencil, but a mold specially used for SMT process. SMT process refers to the installation of leadless or short lead assembly components in printing. On the appearance of the board or the appearance of other substrates, the surface assembly skills of the assembled circuit are soldered or soldered.

1. The solder paste that has not been used up has expired and is used twice.

2. The solder paste scraper is damaged and the stencil is damaged.

3. The equipment parameters such as pressure, viewpoint, speed and demoulding speed of the solder paste scraper are not suitable.

4, the quality of the board, there are inconspicuous coverings on the pad, such as solder resist (green oil) printed on the pad.

5. The fixed clamping of the board in the printer is loose.

6. When the printer is working, there is no timely compensation to increase the solder paste.

7, the quality of solder paste is abnormal, mixed with hard objects such as hard blocks.

8, solder paste missing printed stencil thin and uneven.

9. Solder paste is missing on the stencil or circuit board (such as PCB packaging, stencil wiping paper, foreign matter floating in the ambient air, etc.).

As a special template for SMT production line, SMT steel mesh can be divided into laser SMT steel mesh, electropolished SMT steel mesh, electroformed SMT steel mesh, and SMT steel mesh. The production skills of SMT steel mesh are mainly chemical etching, laser cutting and electroforming.

In the SMT skill, solder paste is the front-end of SMT, and the primary effect of SMT stencil is to help deposit the solder paste, the purpose is to transfer the exact amount of solder paste to the correct orientation on the light stick, and the solder paste is blocked. The fewer the SMT steel grid, the more deposited on the board.