Is it possible to determine flux type?

[Agent24]

A while ago I bought a Kester flux pen from Sparkfun electronics. Turned out I didn't read the datasheet properly and it's actually Organic ACID flux. Wondered why when I didn't clean it, bad things happened...

Was tipped-off by something someone said on here, actually.


Since I still wanted a liquid flux, I looked online and found that Kester also do #186 which is a liquid but rosin based flux - no acid - sounds much better!


I looked on Sparkfun but they didn't sell it, then I looked on eBay and bought some there.

I got it today and I think it's fake. I don't care so much, because I have bought some cheap Chinese paste flux and it works just fine, so if this works too, so what?


But then I got thinking, what if this is also some kind of acid flux, even though they claim it's Rosin-based?

I don't want to use it in that case, because I'd be afraid to get problems again.


Does anyone know if there is there some way I could test the flux and find out what type it really is?

[cmj21973]

Re: Is it possible to determine flux type?

Look up your purchase history on ebay.

Is seller rating in the high 90's?
Under "Other item info" click on History (XXX) number of sold units.
If alot of people have bought it and left good feedback, I wouldn't woory.

With that said, fake flux on ebay does exist. Real way to tell is order same from Digikey, Mouser, or what in your part of the world and compare them side by side.

http://www.bing.com/search?q=fake+so...=0-0&sp=-1&sk=

[PCBONEZ]

Re: Is it possible to determine flux type?

Rosin is an Organic Acid Flux.
http://www.finishing.com/Library/flux.html
http://en.wikipedia.org/wiki/Abietic_acid
.
When they say 'Acid Flux' they are talking about inorganic acids that are much stronger.
~ Yeah, slightly confusing.
.

[Agent24]

Re: Is it possible to determine flux type?

I didn't know that, but this is why I thought #186 was a good one:

The liquid flux I already had is the Kester 2331-ZX which is described as "Organic acid water-soluble flux" and in the datasheet it says "Flux residues after soldering must be removed as they are conductive and corrosive."


The one I just bought is Kester 186 (or a knockoff of it) which says in the datasheet:

"Although the fluxing ability approaches that of Type RA flux, residues after soldering are non-corrosive and non-conductive.... The use of a minimum of ionic activating agents and the inactive nature of the residue permits leaving the residue on circuit board assemblies for many applications."

Thing is... if this flux I got is a knockoff, who knows what is in it? Is it safe to leave on (I am wanting to use it mainly for SMD parts which are hard or impossible to clean underneath of)


Suppose I should really just buy another one from a known reputable store, shouldn't I?

[cellphonebooster]

Re: Is it possible to determine flux type?

wat the hell.............confusing !!

[PCBONEZ]

Re: Is it possible to determine flux type?

I didn't know that, but this is why I thought #186 was a good one:

The liquid flux I already had is the Kester 2331-ZX which is described as "Organic acid water-soluble flux" and in the datasheet it says "Flux residues after soldering must be removed as they are conductive and corrosive."


The one I just bought is Kester 186 (or a knockoff of it) which says in the datasheet:

"Although the fluxing ability approaches that of Type RA flux, residues after soldering are non-corrosive and non-conductive.... The use of a minimum of ionic activating agents and the inactive nature of the residue permits leaving the residue on circuit board assemblies for many applications."

Thing is... if this flux I got is a knockoff, who knows what is in it? Is it safe to leave on (I am wanting to use it mainly for SMD parts which are hard or impossible to clean underneath of)


Suppose I should really just buy another one from a known reputable store, shouldn't I?

There's concerns of acid.
There's concerns of conductivity.
They are related but not the same.

No matter what kind it is it has to be somewhat acidic to remove oxygen from the solder pool.

Those that say you can leave them assume everything reacts and it achieves an electrically non-conductive state.

I don't believe everything works to 'ideal conditions' on every joint like they seem to think so I just clean everything no matter what the ads say.

~~~
If you look at my first link up above there are three basic kinds of "Rosin Core" now, so just saying "Rosin Core" isn't enough to know what they are talking about anymore.
.

[PCBONEZ]

Re: Is it possible to determine flux type?

wat the hell.............confusing !!

There didn't used to be this many different kinds of solder.
.
As best I can remember when I was a kid there were three options:
"electrical solder"[aka Rosin core back then] or "plumbing solder"[aka Acid core back then] or solid core [no flux core].
.
I wasn't actually into electronics back then so if there was something else around I wasn't aware of it.
.
Since then they've come up with wave soldering, SMD, lead free, and several other things all of which work better with 'adjusted' solder and flux chemistry.
There's got to be over 100 different kinds of solder now.
- Very hard to keep up with it all.
.

[Agent24]

Re: Is it possible to determine flux type?

I don't believe everything works to 'ideal conditions' on every joint like they seem to think so I just clean everything no matter what the ads say.

Yeah, I try to do this now too, but like they said in the datasheet, how do you clean under a SMD IC which is against the board?

Especially if there are traces under the IC and board is DIY and has no coating...

[PCBONEZ]

Re: Is it possible to determine flux type?

Coat it and then glue/silicon the part down so flux doesn't get under there in the first place.
- Just a thought...
.