Solder paste printing is a very important process in SMT production line. Many poor reflow oven problems are caused by this process. In the process of printing solder paste, due to the error of human operation, the circuit board is put backwards or the steel net is not in a good position with the circuit board, will lead to the solder paste is mistakenly printed on the circuit board, what should be done in this case?
1. Clean with a spatula
When printing solder paste on the circuit board substrate, to use a scraper to scrape off a layer of solder paste on the circuit board.
2. Wash with washing plate water
But after the scraper is scraped, the solder paste on the pad is not easy to scrape off, so it is also necessary to clean with washing plate water. When washing the plate, we should wash the tin paste with washing water earlier, otherwise, the tin paste will dry out for a long time, and it will not be so convenient when cleaning.
3. Steel mesh wipe paper wipe
After washing plate water cleaning, you can use a special steel mesh wipe paper to clean the circuit board substrate.
4. Air gun dry
Finally, the board is blow-dried with an air gun, and you have a clean, reprintable board.
When cleaning misprinted solder paste, do not use ordinary cloth to wipe solder paste, easy to make solder paste and other pollutants pollution circuit board. We can also use steel mesh cleaning machine to clean, but manual cleaning cost is relatively low, simple and fast, is the current SMT processing plants often used method.
