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emaayan wrote:but the paste bought says that all you need to do is apply it on leads and place the soldering iron to it for a short period, it also says something about weak acid and not to be used on pc boards.
Sounds like you might have solder FLUX rather than solder paste (containing powdered solder). In any case, you normally want rosin-core wire solder for hand soldering. Solder paste can be used with a soldering iron, but you'd normally use it with an oven or hot air.