Solder flux

[GM50 4164]

for the longest time I have been using Radio Shacks rosin solder flux which worked well for me. Being rosin based it somehow got around the opening of the container and then prevented me from being able to screw the lid back on as it would cause it to get stuck! I've left the cover off for so long now that the rosin has dried out and become difficult to use. My question is, what flux do you all use for electrical applications? I know there are liquid based flux out there but have never tried any.

[peteski]

If the stuff you use is 64-022 Non-Spill Paste rosin Soldering Flux in a small white tub, that is the same stuff I use for all my electronic soldering. I love that stuff!!  It might still be available from the Radio Shack website.

I actually move the stuff to a tiny jar for use, and keep the larger tub closed.  That way it lasts me for a long time.

I suspect @robert3985 will eventually chime in with this favorite Superior flux. I use that stuff too, but not for the fine electronic work.

EDIT:  I used to use (and still have) liquid rosin flux, but once I  discovered that Radio Shack  paste, I never went back to liquid.  Just a minuscule amount applied to the soldered area (before soldering) works really well.  When soldering wires to decoder solder pads I apply about poppy seed size amount of paste flux (or even less).  This for me works better than the flux in rosin core solder.

[Chris333]

So I'm sure someone will swoop in and tell me how this is all wrong 

But I have been using Nokorode Regular Paste Flux for as long as I can remember. I lost the lid a long time ago and keep a couple disposable paint dabbers stuck in the tub. I use the same tub of paste to clean the tip of my soldering iron.

https://rectorseal.com/nokorode-regular-paste-flux-group/

One time I tried another type of liquid flux it ate up an aluminum Fast Tracks jig so I never used it again.

[robert3985]

If the stuff you use is 64-022 Non-Spill Past rosin Soldering Flux in a small white tub, that is the same stuff I use for all my electronic soldering. I love that stuff!!  It might still be available from the Radio Shack website.

I actually move the stuff to a tiny jar for use, and keep the tub closed.  That way it lasts me for a long time.

I suspect @robert3985 will eventually chime in with this favorite Superior flux. I use that stuff too, but not for the fine electronic work.

I don't use Superior No. 30 Supersafe Flux for fine electrical work, except to connect wires to rails where I also use 96/4 silver-bearing solder because I don't want my electrical track connections being pulled off while transporting my portable layout sections.

For fine electrical, I use rosin flux also if needed.  Most of the time, I use a multi-core, fine lead/tin solder that has its own flux.  I prefer lead/tin solder for electrical connections because it is less likely to form tin whiskers and short things out...which non-lead solder is infamous for.  I've been using lead-bearing electrical solder since I was a kid and so far (at 73) I am not suffering from any ill effects.  I rather doubt I will since I don't eat it and I wash my hands often.

Cheerio!
Bob Gilmore

[CRR Chase]

for the longest time I have been using Radio Shacks rosin solder flux which worked well for me. Being rosin based it somehow got around the opening of the container and then prevented me from being able to screw the lid back on as it would cause it to get stuck! I've left the cover off for so long now that the rosin has dried out and become difficult to use. My question is, what flux do you all use for electrical applications? I know there are liquid based flux out there but have never tried any.

I like the stuff you use way better than the liquid flux i was using.

[GM50 4164]

I like the stuff you use way better than the liquid flux i was using.

I actually found warming it on low heat in the microwave seems to work well. I did it shortly after making this post and it seems to have worked well, for now!

[mmagliaro]

I use that Radio Shack flux in the white plastic jar with the screw-on lid. Yes, it periodically gets some flux on the surfaces between the lid and jar, and then it starts getting difficult to remove the lid (or get it back on).

A paper towel dipped in acetone will clean the flux off so the lid goes on smoothly.

[MK]

My jar from Radio Shack has lasted me 30+ years and it's still going!   

[djconway]

I think I'm on year 14 or so of my jar of Radio Shack flux, still have a little over 1/2 left.

[peteski]

I was also worried that leaving my Radio Shack tub of flux paste would make it harden up, so quite some time ago (probably around the time Radio Shack closed their retail stores) I moved some of the paste into a smaller container, then put the large tub away tightly sealed.  Oh, when I first opened the large tub I carefully pulled of the security seal, leaving it intact, then I put it in the lid, creating a nice tight gasket.

Using the small container not only keeps the contents of the large tub sealed, the small container takes much less space on my workbench.  And I use so little of the paste that even that small container is still 3/4 full.



Since I use very tiny amounts on small gauge wires and tiny decoder solder pads, I first used sharpened-to-a-flat-end toothpick, but then I also took a Microbrush, cut off the fuzzy head, and flattened that end into a tiny spatula.  The Microbrush applicator is easier to hold.  In the previous photo you can see that the Microbrush has a bent handle.  I did that because when not in use I put it on the small container's rim. But when it was straight, it sometimes rolled off. Now it does not roll off anymore.

[GM50 4164]

Thank you for all the helpful tips! Pete, transferring some to a smaller container is just to simple! lol

[wvgca]

for those that don't want t bother transferring, a few drops of acetone on an open paste flux container will restore the original viscosity, or even make it thinner

[peteski]

for those that don't want t bother transferring, a few drops of acetone on an open paste flux container will restore the original viscosity, or even make it thinner

But acetone evaporates very fast, so the paste will thicken back up rather fast..  If anything, I would think that alcohol  (either 99% isopropyl or denatured) would be a better choice as it evaporates much slower than acetone. I would not use anything weaker than 99% as water (in the diluted alcohol) will not play well with the rosin.

I really didn't think transferring the paste to a smaller container was much hassle.  I only did that once, few ears ago and there is still plenty left in the small container.

[fire5506]

I read somewhere that several people used liquid rosin flux to thin the paste flux and they said it worked very well.

Richard Webster

[JeffB]

But I have been using Nokorode Regular Paste Flux for as long as I can remember. I lost the lid a long time ago and keep a couple disposable paint dabbers stuck in the tub. I use the same tub of paste to clean the tip of my soldering iron.

Same here...   Been using Nokorode for soldering brass, steel, nickel silver and electrical stuff for over 25yrs without any issues.  Though I do clean the soldered joints after soldering with mineral spirits (which works best BTW).

Jeff