Cleaning Agent when soldering

I use flux cleaner!

In the UK it used to be sold with the purple dye methylene violet in and a trace of pyridine to make it unpalatable. A bittering agent is also used to make it harder for people to distil it to pure potable ethanol.

I thought acetone was a component of 'flux off' products, but now I look that up ('Chemtronix Flux-Off Rosin' spray):

so just a soup of methylated hydrocarbons.

Theo

The 2 litre bottle I have is very purple. It says that the colour may fade over time, but doesn't say what the colourant is. These days, I use isopropanol where I once would have used clear industrial meths.

I used to have a de-soldering tool, which had a spring-loaded piston to suck the solder out of the holes. I could never get on with de-soldering braid.

Braid is excellent for surface mount stuff, but you must flux it first. Either standalone flux liquid or a dab of flux-cored solder with the iron to get it going.

The desoldering plunger pump tools are ok for through hole components, where you get more of a blob of solder (the braid will tend to leave a fillet of solder in the hole that prevents the leg from moving), but not much good for surface mount (where there isn't enough solder for the pump to 'grab').

Often the trick with desoldering is to add *more* solder, because it makes for a bigger blob to suck and better heat transfer to melt what's there (then the pump/braid can soak it all up).

Theo

Visa-versa for me I had both a solder sucker and braid and for most jobs braid worked better for me. The braid had to be fairly fresh and not been hanging around for years.

I think surface mount had just about been invented when I was working on PCBs, but it was rare and more for commercial use than the DIY circuit builder.

The small bottle I bought many years ago and kept under the stairs in complete darkness has lost all its original purple colour and is now straw coloured.

Gentian violet iirc, aka crystal violet. Cheap because it's such a strong dye, but lousy lightfastness.

Extraflex is a lot cheaper than braid, scrap co-ax even cheaper. The pvc usually keeps the copper bright, hich is what's needed for desoldering.

What are you actually soldering though? Brian

With the braid method you want to keep the soldering iron on the PCB for the shortest of time possible to prevent overheating and lifting tracks. I'm sure that extraflex and the much larger heat-sink properties of scrap coax braiding would be on sale for this purpose if they were more efficient. The desolder braid needs just enough surface area to heat up fast from the tip of a soldering iron and have enough wire to efficiently wick up all the solder on the board.

With scrap coax - assuming readily available aerial/satellite down-lead i) you have the hassle of first extracting the braid from the rest of the cable. ii) its too bulky to get into small areas iii) its too bulky to heat fast iv) it has to be a good quality cable - the braid in some coax is extremely sparse. v) once removed the braid is probably not woven tight enough to wick up the solder to the extent of the braid specifically designed for the purpose.

I'm sure that I will stick to the more expensive desoldering braid and some liquid/paste flux.

Soldering what?

Electronic stuff nothing - unless obviously dirty.

With copper tube, clean with abrasive strip and use a decent flux. Which applies to most things.

I can only conclude you've never tried it as just about everything you said there is not correct. I can go into more detail if you want.