Solder Flux

[PLUNGER BOY]

The acid or rosin core solders are designed for small electrical jobs .

As noted earlier, one should never use acid core solder on electronics.

Not to split hairs ( BUT ) electrical and electronics are two different animals

[poppo]

Not to split hairs ( BUT ) electrical and electronics are two different animals

Ok. One should not use acid core solder on anything electical. 

[coorslight115]

Why do you guys bother with flux? For the last 15+ years I've just used a 60 40 rosin core solder and haven't had any problems. Thousands upon thousands of solder connections over those years. Just curious

Because it makes soldering a lot eaiser. Plus there is less chance of doing damage from overheating the component as the flux will make the solder flow so much better. And of course because it just makes a better solder connection. 'Back in the day' I was NASA certified for soldering and we were required to use flux.  

IPC-610 says it has to be flux. Actually it depends what you are soldering, if you are repairing a slot then it is not important, if you are repairing F16 or doing something for NASA, it is important. Target class as per IPC610 is very hard to achieve with paste, and if your work does not comply, then the repaired item cannot be used in systems which are responsible for human lives.

Liquid +1   My son works for Northrup Grummen on defense items building and repairing circuit boards and that is all he is allowed to use. So I use it too..but both work. I just have the stuff he is use to on my bench for when he comes over and works on something. Like this connector I having him replace

[poppo]

The liquid stuff works ok, but I prefer paste because it's easier to use the solder (which is in one had and the iron in the other) to dab into it, then having to put one or the other down to pick up the liquid dispenser bottle. When soldering a lot of components, joints, etc. that can get old really fast.

[Apache]

Hi Techs,
    There are different solder flux for different works, you guys have to check data sheets. For example, Regular "Radioshack" solder flux should good for non-tech cable soldering, but not for SMD IC components, neither BGA . BGA solder flux is an "special flux" , it keeps all BGA balls neat in order, if use a different flux the soldering start making mess and shorting the IC. Most important is temperature of work and density of Solder flux.
    Good luck.