I recently came across this video on YouTube, in which the guy is soldering a .5 mm QFP component.
Hand soldering a .5 mm QFP Chip
As I haven't done a lot of soldering in my life (and never used flux), I have a few questions.
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The guy in the video uses only flux without solder to do all of the soldering. How is this possible? What kind of flux is he using? As far as I know, flux is only used as a cleaning chemical during the soldering process. Correct me if I'm wrong.
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He puts flux over the PCB traces and the space between them. If the flux is conductive, how is it possible that there are no short circuits created?
Best Answer
First a warning to readers: That video is an advertisement for a product.
The board you are looking at comes pre-tinned. Applying solder flux removes dirt and oxidation, and makes it easy to use the tin already on the PCB. The flux itself is not conductive.