An important material of quality, a good solder paste can reduce the defects of the board during the production process. So what are the methods to use solder paste?
The basic principle of using solder paste for circuit boards: the shorter the contact time with air, the better. When the solder paste is in contact with air for a long time, it causes an imbalance between the oxidation of the solder paste and the flux ratio. There will be defects such as hard skin, hard blocks, refractory materials and a large number of solder balls on the solder joints of the board.
How to make solder paste more durable?
1. We open the lid as short as possible: open the lid and remove enough solder paste to cover the inner lid immediately. Do not open the lid frequently to expose it to the air.
2. After the solder paste is taken out, immediately cover the inner cover, press hard, and squeeze out all the air between the cover and the solder paste to make the inner cover and the solder paste in close contact. Be sure to press the inner cover, screw on the cover, and put it back in the refrigerator for storage.
3. Remove the solder paste and use it as soon as possible after stirring at an equilibrium temperature.
4. Dispose of excess solder paste that has been removed: After all printing is completed, the remaining solder paste should be recycled to a special recycling bottle as soon as possible and stored separately from the air. Never return the remaining solder paste to an unused solder paste bottle! Therefore, when using solder paste, it is necessary to accurately estimate the amount of solder paste used in the work and the amount of use.
5, the problem: If the surface of the solder paste appears hard, hard, do not stir! Be sure to remove hard skin and hard blocks. The remaining solder paste should be tested before it is officially used. If you can't do this, you can only discard it.