Soldering Flux

[Achraf]

Hi all,

I have a problem with a flux I have used since 15 years ago. It works ok, but it turns dark with the time and get an unpleasant black/grey aspect. This flux contains zinc chloride and formic acid dissolved in water and white fixing vaseline.

Anyone could help me?

Thanks in advance

[Ian.M]

Acid Zinc Chloride fluxes are totally unsuitable for electronics and electrical work.  Their residue is extremely corrosive and gets up under the wire insulation and under components on PCBs, and other places where its impossible to totally remove it, resulting in early failure of whatever you soldered with it.

Therefore, unless you only use this flux for plumbing and tin-smithing, (and even for those applications it needs careful cleaning afterwards), go and buy some electronics grade halide free rosin based flux.