How to Select a Welding Rod

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Shielded metal arc welding (SMAW), more commonly referred to as stick welding, is a technique that runs an electrical current through a flux-coated electrode into the metal being welded.

The process creates an electrical arc when the welding rod touches the metal that creates sufficient heat to melt the parent metals and the rod, fusing them in a weld bead. Selecting a welding rod depends on the thickness, type and condition of the metal you are attempting to weld, as well as the type of electrical current you are using.

Read the welding rod codes. Each welding rod is stamped with a five-digit code designation such as E6011. The letter "E" refers to the electrical arc welding process. The first two numbers refer to the tensile strength of the metal in the rod after it forms a weld bead. The third number refers to the electrode position. The last two digits refer to the flux coating on the rod, which correlates to the type of current to be used.

Select the proper welding rod diameter. The diameter is correlated to the thickness of the metal sheet you are welding. Therefore, for 1/4-inch-thick sheeting, use a 1/4-inch-diameter welding rod. When welding a sheet that is in between rod diameter sizes, select a rod that is slightly larger in diameter than the thickness of the sheeting.

Determine the type of electrical current needed for the welding you are performing. DC current can be used with either the welding rod attached to the positive or negative electrode. A DC positive current will leave a deeper penetrating weld, whereas a DC negative current will produce a weld seam of medium depth.

Identify the tensile strength required for the welding rod. A rod that begins with the number 70 will have a strength of 31751 Kilogram per square inch, a rod that begins with the number 65 will have a strength of 65,000, and so on. Although the tensile strength required for a weld is determined by the type and application of the metal being welded, to avoid joint failure you should choose a rod tensile strength that is greater than the rated strength of the metal being welded.