Using soldre flux on electronics?

[mm]

I've bought at the store or at yard sales, or found in the trash or inherited from an old guy several kinds of flux, but I've alsways saved them for copper pipes, and relied on resin core solder to do electronics and electrical.

Is this what you guys do?

Sometimes I have trouble getting the solder to spread out, even when I've scraped the wire etc. with a knife and gotten it very shiny.

One case last week involved 20 gauge single strand wire that had a white plastic covering and a black plastic covering over that, even though there was no braid or anything (why two layers?)

Should I be using the flux in cases like this?

Are there any things I should know that aren't obvious among the following:

Oatey No.5 solder paste, cleans, fluxes, in a round red can a half inch high Oatey No. 95 Lead Free Tinning Flux for use with any lead free solder, in a green can the same size as the red can above. Kester soldering paste, in a 2x2" square blue metal can about a half inch high with rounded corners. Kester All Purpose Soldering flux, liquid in a 4 oz white plastic bottle.

[Joe]

For many years Ersin multicore 60/40 solder was the yardstick for all the others. Likely today there are other even better ones. For anything electrical stick with one of these and if your work doesn't turn out too well you simply aren't getting the copper clean enough nor the work hot enough for solder flow. HTH

Jpe

[Art Todesco]

Just about any flux left on wires/PC boards will corrode the metal in time. That is why electronic companies wash the boards after the components are soldered. However, flux meant for electronics can usually be left without cleaning .... but it will still cause problems after a long time. BTW, I have a "Kester soldering paste, in a 2x2 square blue metal can" that I have had for many, many years of electronic soldering. It's so old, the can is marked something like

19 cents. It's still pretty full.

mm wrote:

[mm]

So you mean I shouldn't need any other flux that what is in the solder? Like i have been doing?

[badgolferman]

I can only tell you my experience as an electronic technician for 25 years. If you cannot tin the single strand wire properly it is either coated with some substance or you are not heating it enough. Come to think of it, why are you tinning single strand anyway? Perhaps I misunderstood and you just want to solder it on to a post or something. You really shouldn't need any additional flux. What is in the solder should be good enough.

[mm]

That ought to be good enough. :)

Sometimes it is just part of the soldering, but last week I was doing the strand in advance because I was soldering to pcb traces and I wanted it to go quickly.

That too in some cases.

Then I'll stick with my long-time practice, which usually works fine.

Thanks, and thanks all.

[Toller]

I have heard that, but why doesn't it corrode copper pipe? Presumably it has to do with the mass of the pipe, or is it the metal alloy?

A couple years ago I was connecting 4 pieces of #10 wire together and couldn't twist it adequately to get a wire nut on. I soldered them together with plumbing flux and plumbing solder, and then put a wire nut over the whole thing. I figure it meets code, as the wire nut is the primary connector (once I was able to get it over the wires, that is). Does the plumbing flux somehow endanger the wire, or is the #10 heavy enough that it doesn't matter.

(Actually, now that I think about it, I am pretty sure I used the flux that came with the soldering iron; though I used a propane torch as the little soldering iron wasn't putting out enough heat for all that wire. That would be electrical fluxwouldn't it? But still, would plumbing flux hurt the #10?)

[Art Todesco]

[badgolferman]

Purest alcohol you can find.

[Art Todesco]

I usually don't bother, however, if I am doing a board with very narrow traces, i.e. the firewire connector on a video editing board, I will clean it after soldering. Alcohol is ok. I also use spray contact cleaner with a stiff brush .... a metal handle glue/flux brush with the bristles cut about half way. I have also used "Carbo-Solv" or something like that.

[mm]

OK. I'll be good and I'll do like what you two say. Thanks again.

[Jim Yanik]

"badgolferman" wrote in news: [e-mail]:

90% isopropyl from the drug store works fine,and is inexpensive. Apply with a Q-tip,it absorbs the dissolved flux/alk from the work.

some rosin-core solders are "no-clean",some are water-cleanable.

(21 yrs at Tektronix.)

[Jim Yanik]

mm wrote in news: [e-mail]:

On really micro electronics,"cleaning the flux off" merely drives some of it into where you don't want it.

although a final rinse with no-residue spray cleaner is a good idea.