JacobsParts Inc. SL50-03 63/37 Rosin Core Solder 0.38mm 50g

63/37 rosin-core solder wire 0.38 mm

This 50 g spool contains a eutectic 63 % tin and 37 % lead alloy with 2.0 % flux inside a 0.38 mm diameter wire. The true melting point is 184.5 °C (361.4 °F) rather than a melting range. It is intended for hand soldering of electronic circuitry where low thermal stress is required. No batteries are needed.

Thin gauge for dense boards

The 0.38 mm diameter feeds easily through fine-pitch component leads and surface-mount pads. Because the alloy melts at a single temperature it wets quickly, reducing the time a hot iron must stay on sensitive parts. The rosin flux cleans oxidation during the joint formation, so separate flux application is often unnecessary. The 50 g spool provides enough length for many small assemblies.

Consistent flow during long sessions

The eutectic composition avoids the pasty stage common in non-eutectic solders, so the wire keeps flowing steadily even when joints are made in rapid succession. Flux residue remains non-corrosive after cooling, leaving boards clean without extra cleaning steps. The low melting point protects heat-sensitive components throughout extended soldering work.