The old plumber who taught me to solder had 3 basic rules:
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?1. Cleanliness is the key to success - surfaces to be soldered MUST be cleaned to bright, shiny metal.
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?2. Flux is your friend - apply it to all surfaces before heating.
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?3. Solder flows towards the heat source - that was before hot melt glue guns were common.? The basic idea was to apply heat to the area you want the solder to flow towards, not the outer surface.
