Eastwood 21307 Radnor ERCuSi-A Silicon Bronze TIG Welding Rod 3/32" x 36" 1lb Tube

The Radnor ERCuSi-A Silicon Bronze TIG Welding Rod is a copper-based filler metal classified under AWS A5.7 / ASME SFA-5.7, designed for GTAW (TIG), MIG, and oxyacetylene welding applications. Each 1 lb tube contains 36-inch precision-cut rods in a 3/32" (2.4 mm) diameter, making it well-suited for a wide range of copper alloy and steel joining tasks.

Key Features:

• AWS Classification: ERCuSi-A per ANSI/AWS A5.7 and ASME SFA-5.7
• Copper-silicon alloy composition with approximately 3% silicon content, plus trace amounts of manganese, tin, and zinc
• As-welded tensile strength: 50,000 PSI
• Approximate melting temperature: 1,866°F (1,019°C)
• Low heat input minimizes warping and burn-through on thin-gauge sheet metal
• High silicon content produces flat, consistent weld seams
• Excellent corrosion resistance — suitable for surfacing parts exposed to corrosive environments
• Runs on 100% argon shielding gas, DCEN (straight polarity) for TIG applications
• Diameter: 3/32" (2.4 mm) | Length: 36" | Pack weight: 1 lb

Applications: Silicon bronze TIG welding rod is ideal for joining copper, copper-silicon, copper-zinc (brass), and bronze base metals to themselves or to steel. It is widely used for braze-welding plain or galvanized steel sheet metal in applications such as automotive bodywork, steel cabinets, metal furniture, and ductwork. It can also be used on coated steels and for surfacing components subject to corrosion.

Welding Tips: Keep the weld puddle small to allow fast solidification and minimize hot cracking. When working with silicon bronze base metal, keep interpass temperature below 150°F. For oxyacetylene welding, use a slightly oxidizing flame and a borax-type flux before and during welding.