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Took me 5 years to figure out I was cleaning flux wrong

I used to scrub boards with isopropyl alcohol and a toothbrush then blow them dry. One day I repaired a vintage receiver from 1978 and the owner said the board looked "foggy". That's when I learned you need to use deionized water first then alcohol to get all the residue off. Now I do a 3 step wash and haven't had a single cold solder joint since. Anyone else find out they were skipping a basic step for way too long?
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3 Comments
the_elizabeth
Man, that foggy board thing would drive me nuts. I used to be one of those "just alcohol and elbow grease is fine" people, honestly thought the extra steps were overkill for hobby stuff. But after reading a repair blog a couple years back I gave the deionized water first method a shot on a crusty old amp and it was night and day. The residue that came off in that second alcohol pass was ridiculous, never going back to the shortcut now.
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lisab32
lisab3214d agoMost Upvoted
Does the type of solder make a difference with that method?
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logan_anderson40
Agree with @the_elizabeth, I used rosin core and it worked fine after that water soak.
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