Regarding Flux and IPA

[Dokroma]

Hi, how do you apply flux from a tub? I have rosin core flux, do I use something like a toothpick to coat the pins before soldering? Also, how do you then clean it off? Do you use isopropyl? Do you just get a Q tip and wipe down the board with the IPA?

[jmelson]

Hi, how do you apply flux from a tub? I have rosin core flux, do I use something like a toothpick to coat the pins before soldering? Also, how do you then clean it off? Do you use isopropyl? Do you just get a Q tip and wipe down the board with the IPA?

If you want to clean it, use water soluble (WS) flux.  SO much easier to clean off.  Otherwise, IsoPropyl or denatured (ethyl) work, if you scrub with a toothbrush.

Instead of a toothpick, I use a bit of solid-core wire, dip in flux and wipe on pins.

Jon

[mayor]

If you want to clean it, use water soluble (WS) flux.  SO much easier to clean off.  Otherwise, IsoPropyl or denatured (ethyl) work, if you scrub with a toothbrush.

Instead of a toothpick, I use a bit of solid-core wire, dip in flux and wipe on pins.

Jon

Isn't water-soluble flux quite corrosive? ie, ensure a really thorough clean if you use.

[ceoxrad]

If you want to clean it, use water soluble (WS) flux.  SO much easier to clean off.  Otherwise, IsoPropyl or denatured (ethyl) work, if you scrub with a toothbrush.

Instead of a toothpick, I use a bit of solid-core wire, dip in flux and wipe on pins.

Jon

Isn't water-soluble flux quite corrosive? ie, ensure a really thorough clean if you use.

It is, and cleaning with DI water and a suitable detergent is mandatory, for hobby use I think is quite a pain actually. better to stick to rosin (RMA, or RA if you work on tough boards) and then clean with IPA or a commercial flux cleaner.
Acetone can also be used, but only in special cases and with utmost care (can dissolve component legends and some plastics, cheap solder mask can be attached too!)

[jmelson]

If you want to clean it, use water soluble (WS) flux.  SO much easier to clean off.  Otherwise, IsoPropyl or denatured (ethyl) work, if you scrub with a toothbrush.

Instead of a toothpick, I use a bit of solid-core wire, dip in flux and wipe on pins.

Jon

Isn't water-soluble flux quite corrosive? ie, ensure a really thorough clean if you use.

It is, and cleaning with DI water and a suitable detergent is mandatory, for hobby use I think is quite a pain actually. better to stick to rosin (RMA, or RA if you work on tough boards) and then clean with IPA or a commercial flux cleaner.
Acetone can also be used, but only in special cases and with utmost care (can dissolve component legends and some plastics, cheap solder mask can be attached too!)

I'm using SRA water-soluble flux I buy on eBay.  You get a flux pen (sort of like a fiber marker, but bigger) and a refill bottle.
Just a couple seconds in running water has the board absolutely spotlessly clean.  I scrub for a few seconds with a toothbrush just to make sure.

Jon

[KL27x]

The paste rosin flux in a tub is more useful for dipping the ends of largish wires in there. Pretty much all it's good for. For board/component level soldering, liquid flux is more convenient. Apply to the board, generally, not the components.