Why do solder always stay on the soldering iron instead of the circuit board when soldering it with a soldering iron?.
The first iron to clean, second iron to apply flux, third temperature is good
No welding circuit board to smear a good welding flux is of good quality
The reasons may be as follows:First, your circuit board soldering tin is not plated, you should first coated with soldering flux, and then tin plating.Second, the soldering iron is not on the pad. This is caused by improper operation. The heat conduction is tin, not the soldering iron head, so the tin is placed on the pad to heat up.
