What should you consider when choosing a Solder Wire for your assembly process.

At Solderking we know that choosing the correct solder wire is essential for achieving high quality solder joints and ensuring the reliability of your electronic assemblies. Solder quality has evolved over the years due to advancements in materials science, manufacturing processes, and industry regulations. I thought it would be handy for some if I created a guide on how to choose the correct types of solder wire. When you work yourself back from the assembly process, you find there are some very interesting considerations to factor in, enjoy!

Solder Composition: Solder wire is typically made from various metal alloys. The most common types include lead-free solder (e.g., Sn-Ag-Cu or Sn-Cu) and leaded solder (e.g Sn-Pb). Today's electronic projects mainly require compliance with environmental regulations, opt for lead-free solder. However, leaded solder may still be required for certain applications.

Diameter and Thickness: The diameter of the solder wire affects the amount of heat transfer and the size of the solder joint. For general electronic assembly, a solder wire diameter of 0.56mm to 1.20mm is commonly used. Thicker wire is suitable for larger components and joints, while finer wire is useful for delicate work.

Application: Solder wires vary in performance depending on the application and what is expected. Robotic soldering applications require a fast flowing, consistent soldering speed with 3.3% flux core being the preferred choice. Most hand soldering applications have found the 2.2% flux grade to be the ideal choice.

Flux Core: Solder wire often comes with a flux core, which helps to clean the surfaces being soldered and improve solder flow. There are various flux types, such as Rosin Based (CXW-70), Water Soluble (WS) and Acid Based (KingsFlux)

Flux Residue: Consider the flux residue left behind after soldering. Some applications may require complete removal of flux whilst others may be suited for the residues to be left on the board.

Application and Materials: Consider the type of materials you'll be soldering. Different alloys and flux types may be better suited for specific materials, such as copper, brass, or nickel.

Temperature and Melting Point: Choose a solder wire that melts at a temperature suitable for your soldering iron or station. Make sure the solder wire's melting point matches the soldering temperature you intend to use.

Brand and Quality: Opt for reputable brands that produce high-quality solder wire. High-quality solder typically contains consistent alloy compositions and flux formulations, leading to better soldering results.

Environmental Considerations: If you're working on projects that require compliance with environmental standards, make sure to choose solder wire that meets those requirements, such as RoHS (Restriction of Hazardous Substances) compliance.

Personal Preference: Over time, you may develop a preference for a particular type of solder wire based on your experience and the specific projects you work on. Experiment with different types to find what works best for you.

Remember that the choice of solder wire can influence your soldering results, so take your time to consider these factors and make an informed decision based on your specific needs and preferences.

Solderking Assembly Materials Limited

An independent, UK manufacturer of solders and chemical consumables for the assembly of electronic, electrical and engineered parts.

Solderking specialises in the development, manufacture and distribution of regulatory compliant soldering assembly materials to RoHS, REACH and the responsible minerals initiative.

For help with your soldering requirements, contact our team [email protected] +44 (0)1262363088