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Removing excessive flux

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Removing excessive flux

By artelse
-  Tue Aug 21, 2007 5:04 am #34057
Another simple question, what is the best way to remove excessive (burnt) flux?

What chemical is safe without damaging the masks?

Thanks,

ae
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By leon_heller
-  Tue Aug 21, 2007 5:12 am #34058
IPA is best - iso-propyl alcohol, not India Pale Ale. 8-)

Leon
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By phalanx
-  Tue Aug 21, 2007 5:42 am #34061
Mmmm.... IPA! I need a beer!

Anyhoo, isopropyl alcohol works great like Leon said. I typically dip a cotton swap in it and then gently scrub the areas that need attention. If there is any residue afterward, a rinse with distilled or deionized water usually takes care of it.

-Bill

By beebop
-  Tue Aug 21, 2007 8:03 am #34067
Yep, IPA, but I'm a bit rougher - this is what I save my old toothbrushes for.
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By leon_heller
-  Tue Aug 21, 2007 8:46 am #34070
I use an old toothbrush as well. Flux can be quite hard to remove if it has been there for a long time.

Leon

By artelse
-  Tue Aug 21, 2007 3:50 pm #34088
Thanks for the answers. It's interesting to note the difficulty in finding answers to these basic soldering questions.

Great.
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Re: Removing excessive flux

By bigglez
-  Tue Aug 21, 2007 4:46 pm #34089
artelse wrote:Another simple question, what is the best way to remove excessive (burnt) flux?

What chemical is safe without damaging the masks?
Greetings ae,

I use MEK (methyl ethyl ketone aka Butanone). It can be purchased from Home Despot or other similar stores. It is safe but requires ventilation.

My usual method is to apply it with Q-tip cotton swabs, being careful not to contaminate the bulk container.

Comments Welcome!

By Philba
-  Tue Aug 21, 2007 9:52 pm #34095
I'd be a little careful with MEK. I got a nasty burn from it when some spilled on my pants and I didn't get them off real fast. It took about 3 months to heal.

Also, MEK will dissolve some plastics be careful with it. I prefer IPA (well, both kinds) since it's pretty benign.

I bet MEK cuts that flux like crazy, though!

By rpcelectronics
-  Fri Sep 07, 2007 4:45 pm #34813
At work and at home, I like to use PrintKote. I THINK it's a variation on MEK, but I don't know for sure. Works great for removing flux, even after it has set up and been on the board for a long time. I use one of those little diposable stiff horse hair brushes.

Just my $0.02,
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