Is there any adverse effect of manual tin dipping on PCBA board with flux? (No preheating in advance)

Flux usually plays two main roles on PCBA board: first, it helps to improve the welding quality and make solder easier to attach to solder joints; Secondly, it can protect the welding surface from oxidation and corrosion.

However, if you dip the flux directly on the PCBA board by hand, it may lead to the following adverse effects:

1.

Contaminated circuit board: When tin is dipped by hand, too much solder may be coated on the circuit board, exceeding the amount required for soldering. This may lead to a short circuit between solders or block a small gap in the circuit, resulting in poor connection or abnormal operation of the circuit.

2.

The quality of solder joint becomes worse: flux usually needs to be decomposed and volatilized during the welding process, so that the solder directly contacts the solder joint. If you dip the flux directly on the PCBA board by hand, the flux may not be completely decomposed and volatilized, and it will remain around the solder joint. These residues may reduce the contact quality between solder joints and pads, resulting in the deterioration of solder joints.

Therefore, it is suggested to use professional welding equipment when dipping tin PCBA board to ensure the control and quality of welding process. If flux is needed, it should be properly decomposed and volatilized to avoid the above problems. At the same time, we should also pay attention to the appropriate welding temperature and time to ensure the welding quality and the integrity of the circuit board.