Drag soldering works exactly as its name implies, by dragging a bead of solder across fine-pitch pins you can quickly solder an entire row. The method relies on clean joints, so liquid solder flux is
UltraKeet Australia - Temporary solder masking with Kapton Polyimide Film
UltraKeet Australia - Temporary solder masking with Kapton Polyimide Film
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Page 8 – RAYPCB
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