Solder Wire Product Guide
CHOOSE THE RIGHT MELT. BUILD A BETTER JOINT.
Professional solder wire for electronics repair, rework, and assembly. Choose 138°C lead-free Low Melt for reduced heat exposure or 183°C Sn63/Pb37 Medium Melt for dependable everyday soldering performance.
Two Alloys.
Two Temperature Ranges.
Different soldering jobs require different thermal profiles. PolarTronix Low Melt and Medium Melt Solder Wire give technicians two professional options for precision electronics repair, rework, and assembly.
Sn42 / Bi58 Low Melt Solder Wire
Lead-free low-temperature solder wire designed for precision electronics repair and rework where reducing heat exposure can be beneficial.
Sn63 / Pb37 Medium Melt Solder Wire
Eutectic solder wire designed for dependable everyday electronics soldering, PCB repair, assembly, and professional rework applications.
Choose the Alloy for the Job.
Choose 138°C Low Melt when lower melting temperature and reduced heat exposure are important. Choose 183°C Medium Melt for dependable general electronics soldering and everyday professional repair work.
Choose the Right
Solder for the Job.
Both PolarTronix solder wires are designed for professional electronics work, but their alloy, melting point, wire diameter, and ideal use cases differ. The right choice depends on how much heat the repair can tolerate and the type of soldering work being performed.
Lower Heat Exposure Matters.
The 138°C Sn42/Bi58 alloy is especially useful when a lower melting temperature can help reduce the amount of heat introduced during delicate electronics rework.
- Heat-sensitive components
- Connector replacement
- Precision microsoldering
- BGA and board-level rework
- Trace and pad repair
- Lead-free low-temperature work
You Need Everyday Soldering Performance.
The 183°C Sn63/Pb37 eutectic alloy is a dependable choice for general electronics soldering, repair, prototyping, assembly, and repeatable professional work.
- General PCB repair
- Through-hole soldering
- Electronics assembly
- Prototyping
- Industrial and control boards
- Everyday repair-bench soldering
45°C Separates the Two Alloys.
Melting Point Is Not Iron Temperature.
The 138°C and 183°C values describe the melting points of the solder alloys. Actual soldering-station temperature depends on factors such as joint size, tip geometry, thermal mass, equipment, workflow, and the components being serviced.
One Repair Bench.
Two Soldering Options.
Both PolarTronix solder wires are built for professional electronics work. The main difference is where each alloy provides the strongest advantage: Low Melt for lower-temperature precision rework, and Medium Melt for dependable everyday soldering.
Board-Level Repair
Suitable for professional circuit-board repair, component replacement, solder-joint service, and electronics rework.
Microsoldering
Useful for detailed electronics work where controlled solder delivery and consistent alloy behavior are important.
Surface-Mount Work
Supports SMD and SMT repair workflows involving small electronic components and board-level connections.
Phones & Tablets
Fits professional mobile-device repair, connector service, board repair, and component-level soldering workflows.
Game Console Repair
Suitable for console motherboard repair, connector service, component replacement, and general electronics rework.
Laptops & Desktops
Useful for computer motherboard repair, power circuits, connectors, through-hole components, and general soldering.
Delicate & Heat-Sensitive Rework
The 138°C Sn42/Bi58 alloy is especially useful when reducing the amount of heat introduced to the repair area is a priority.
- Heat-sensitive component work
- Connector replacement
- BGA repair and rework
- Trace and pad repair
- Fine-pitch electronics work
- Lower-temperature assembly
Everyday Professional Soldering
The 183°C Sn63/Pb37 eutectic alloy is a dependable general-purpose option for routine repair, assembly, prototyping, and professional electronics work.
- Through-hole soldering
- General PCB repair
- Electronics assembly
- Prototyping
- Audio electronics
- Industrial and control boards
Built for Repair, Rework & Assembly.
Match the Solder to the Repair.
The best solder wire is not determined by melting point alone. Consider the component, PCB construction, thermal sensitivity, joint size, soldering equipment, and the alloy already present when selecting the appropriate material.
Understand the Alloy.
Control the Heat.
The melting point tells you when the solder alloy transitions into a liquid state. PolarTronix Low Melt and Medium Melt Solder Wire use different alloys, giving technicians two distinct thermal profiles for different repair and assembly requirements.
Lower-Temperature Soldering Alloy
Sn42/Bi58 melts at 138°C, allowing the solder alloy to transition at a lower temperature than conventional Sn63/Pb37 solder. This can be useful when reducing thermal exposure during delicate electronics rework.
Eutectic Soldering Alloy
Sn63/Pb37 is a eutectic alloy with a defined 183°C melting point, providing a direct transition between solid and liquid states during general electronics soldering and repair.
Melting Point ≠
Soldering Iron Setting
The alloy melting temperature does not tell you exactly what temperature to set your soldering station. The iron tip must transfer enough energy into the joint for the solder and surrounding materials to reach the required working temperature.
Joint Size Matters
Large ground planes, connectors, and heavier joints absorb more heat than small component leads.
Tip Geometry Matters
Tip shape and contact area influence how efficiently heat transfers from the soldering iron into the joint.
Station Performance Matters
Heater power, temperature recovery, calibration, and tip condition can all affect soldering performance.
The Repair Matters
Component sensitivity, board design, existing alloy, flux, and repair technique all influence the working temperature required.
Select the Alloy
Choose Low Melt or Medium Melt according to the repair, existing solder system, component sensitivity, and desired thermal profile.
Match the Equipment
Use an appropriate soldering tip, station, and flux for the size and thermal mass of the joint being serviced.
Control Heat Exposure
Use enough heat for efficient solder flow while avoiding unnecessary heating time around sensitive components and board materials.
Temperature Is Only Part of the Process.
Successful soldering depends on the complete thermal system—not just the number on the station display. Alloy, flux, joint mass, tip geometry, equipment performance, and contact time all work together during a soldering process.
Two Professional
Solder Wire Formulas.
PolarTronix Low Melt and Medium Melt Solder Wire provide two distinct alloy and temperature options for professional electronics repair, rework, prototyping, and assembly.
Sn42 / Bi58
Lead-free low-temperature solder wire for precision and heat-sensitive electronics rework.
Sn63 / Pb37
Eutectic solder wire for dependable everyday professional electronics soldering and assembly.
Lower Heat Exposure
138°C melting point supports lower-temperature rework where reducing thermal stress is beneficial.
Eutectic Performance
Sn63/Pb37 transitions directly at 183°C for dependable general electronics soldering.
0.5 mm & 0.8 mm
Two wire diameters support finer precision feeding and broader general-purpose solder delivery.
50 Gram Spools
Practical spool size for professional repair benches, technical labs, and regular soldering workflows.
138°C or 183°C — Match the Alloy to the Repair.
Two Melt Points.
One Professional Workflow.
Choose 138°C Sn42/Bi58 Low Melt for lower-temperature, precision electronics rework, or 183°C Sn63/Pb37 Medium Melt for dependable everyday soldering, PCB repair, assembly, and professional bench work.