69100508 - Bonarc ER70S-6 Mild Steel MIG Wire .030 - 5kg Spool

High-Performance ER70S-6 Mild Steel MIG Wire

The Bonarc ER70S-6 MIG Wire (.030" diameter) in a 5kg spool is a premium general-purpose welding consumable designed for the Gas Metal Arc Welding (GMAW) process. Engineered to meet strict AWS A5.18 standards, this solid mild steel wire is classified as ER70S-6, indicating a chemical composition rich in deoxidizers. Specifically, the "S6" designation signifies higher levels of manganese and silicon compared to standard S3 wires. These added deoxidizers act as powerful cleaning agents within the weld pool, effectively scavenging oxygen and impurities. This makes the Bonarc S6 wire exceptionally forgiving when welding on base metals that may have light rust, mill scale, or oil present, ensuring sound, porosity-free welds even in less-than-ideal surface conditions.

One of the critical features of this wire is its high-quality copper coating. This coating serves multiple technical functions: it enhances electrical conductivity at the contact tip for a stable arc, protects the steel wire from oxidation during storage, and significantly improves feedability. The smooth surface finish reduces friction within the torch liner and gun, minimizing the risk of bird-nesting or irregular feeding, which is crucial for maintaining consistent weld parameters in both manual and automated setups. The 5kg spool size offers a balance between portability and capacity, making it suitable for light industrial fabrication, maintenance shops, and field repair work where full-sized 33lb or 44lb spools may be cumbersome.

Mechanically, the deposited weld metal exhibits excellent tensile strength (typically exceeding 70,000 psi) and ductility, making it suitable for structural applications, automotive frames, and general machinery fabrication. The wire is designed to operate with DCEP (Direct Current Electrode Positive) polarity and is compatible with a variety of shielding gases. While 100% CO2 provides deep penetration and cost-effectiveness, using an Argon/CO2 blend (such as C25) will yield a smoother arc, reduced spatter, and a more aesthetically pleasing bead profile. This versatility allows the Bonarc ER70S-6 to adapt to various welding procedures and joint configurations, from butt welds to fillets, in all welding positions.

In summary, the Bonarc .030" ER70S-6 wire provides industrial-grade performance with a focus on arc stability, wetting action, and impurity tolerance. It is an essential consumable for professionals requiring reliable, high-strength joints on mild steel without the extensive pre-weld cleaning often required by other wire classifications.