What causes Solder Paste to clog the stencil after screen printing? This is a common issue in actual operations. For example, excessive squeegee pressure can cause solder paste to squeeze out and block the mesh openings. In this case, the squeegee pressure must be adjusted.

Another possibility is that the solder paste is too thick or has an inappropriate viscosity. If the solder paste has poor flowability, it can easily get stuck in the stencil apertures. It is necessary to select the appropriate solder paste model to ensure good flowability.

In addition, infrequent stencil cleaning can also cause clogging. Residual solder paste left on stencils that have not been used for a long time can easily cause blockages the next time they are used. Therefore, they must be cleaned thoroughly after each use.

Have you paid attention to the tilt angle of the board during solder paste printing? If the board is not placed flat, the solder paste will be unevenly scraped to one side, leading to local blockages. Ensure the board is placed horizontally.

Another possibility is that the printing speed is too fast. If the speed is too high, the solder paste may dry before it has fully spread, causing clogging. It is necessary to appropriately reduce the printing speed.

Finally, check whether the squeegee is severely worn. An uneven squeegee edge will affect the solder paste scraping effect and easily leave residue. Replace or repair the squeegee regularly.

The key to prevention lies in daily maintenance. Check the condition of the stencil and squeegee before daily printing to ensure there is no foreign matter. Solder paste should be used as soon as possible after opening to avoid deterioration from prolonged exposure to air.

When encountering stencil clogging, do not rush to replace the stencil. First try cleaning it with special tools, and consider replacement only if that is ineffective. This can save costs.

Operators should be familiar with equipment parameters and be able to adjust settings according to actual conditions. Parameters such as temperature, pressure, and speed all need to be reasonably controlled.

Solder paste clogging the stencil does not happen by chance. As long as attention is paid to details in daily work, the occurrence of this situation can be effectively reduced.