What's the soldering flux inside the solder wire?
Rosin come, if it will splash is too large if rosin, rosin too much not only will splash and residue of black objects, strong solder can be free for you to solve this kind of problem
Most of rosin resin (RO), some organic compounds have the effect of flux (OR). Each manufacturer has a different model, please combine your own production and cleaning methods to buy their own solder wire.
Solder, solder wire inside the main ingredients are rosin, but there are also some high requirements of solder wire welding, which is composed of a variety of chemical composition, process.
