E.g., "C-Flux":
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What's the advantage? You still have to apply solder to the joint. What's the difference if you plain-flux & solder, or C-flux & solder?The linked web page says "Flows smoothly into even the smallest cavity". Is that the advantage - that solder flows into the joint _better_? I just had a plumbing job with about 60 joints. 2 leaked. Would the use of C-flux been better?
Thanks, Bob