How to Silver Solder Mild Steel with SSF-6

This video demonstrates how to silver solder mild steel with an oxyacetylene torch and SSF-6 high strength silver solder.

Mild steel is a commonly used, durable, inexpensive metal alloy containing up to .3% carbon. The low carbon content creates a metal that is both ductile and malleable, and can be utilized in a variety of products such as:

  • fence posts
  • street signs
  • construction
  • motorcycle frames
  • scaffolding
  • shelving and more

Mild steel is identified by its softness (as compared to other steels) and is frequently used in electronics due to its magnetism and ability to conduct electricity without damaging the appearance of the base metal. Steel becomes harder and stronger as the carbon content increases, resulting in durable rust-proof steels such as stainless steel. Mild steel is rarely used in applications which require structural strength, such as load bearing projects or structural beams.

Both low-carbon mild steel and high-carbon stainless steel can be effectively brazed with SSF-6 56% Silver Solder and an oxyacetylene or propane torch (with a proper tip)

In this how-to video, a piece of square steel is joined with rectangular steel using a brazing technique, SSF-6 and an oxyacetylene torch. Notice how the proprietary flux coating melts and flows when the mild steel turns to a dull red, indicating the proper moment to apply the silver brazing rod to the parent metal

SSF-6’s high silver content (56%) provides a perfect color match and better finish than MIG welding, with a bond of over 70,000 PSI.


  • Be sure to pre-clean mild steel prior to brazing or soldering, as impurities can impede the flow of the silver solder’s flux.
  • When pre-heating, observe the color change of the steel, indicating proper application temperature.  (Avoid bright red steel)


NotePlease observe all AWS Safety & Health Guidelines when using Muggy Weld products.