Question 3-79L2

Removing solder from plated-through holes requires a method that extracts the molten solder without damaging the delicate copper plating, pads, or board substrate. A vacuum device, such as a desoldering pump (solder sucker) or a desoldering station with a vacuum feature, gently and efficiently pulls the molten solder out of the hole. This minimizes thermal stress and mechanical force on the board. A dental pick (A) relies on mechanical force, which can easily scratch, damage, or even lift the copper plating inside the hole or the surrounding pads. Using a soldering iron tip at 900 degrees F (C) is excessively hot; most solders melt between 360-500 degrees F. Such extreme heat risks delaminating the board, burning the solder mask, or damaging adjacent components. An air jet device (D) alone would simply blow molten solder across the board, potentially creating shorts or contaminating other components, rather than cleanly removing it.