The radioactivity is of a low level, but it can be a hazard, especially if radioactive dust is generated when grinding the electrodes to a point. New tungsten materials now are available, such as lanthanated electrodes, which offer superior arc welding characteristics and are safer because they lack radioactivity. Sharper Versus Blunt Electrodes. Sharper electrodes have less arc wander at lower amperages, more consistent arc starting, and a wider arc. More blunt electrodes have a longer life, provide deeper weld penetration for the same amperage levels, and can handle higher amperage levels.
Higher currents can use larger included angles.
RPM Average welding current levels Use 1 amp of welding current per 0.001 inch of material thickness. Downslope the weld at weld termination to form a gradual taper with a length approximately two to three times the weld width. If heat builds in the part, causing excessive weld pool size or excessive weld penetration at the final stages of the weld, use multiple levels to decrease the weld current gradually as the part is welded. From this, a company can realize lower costs per unit of product, quicker delivery of product, and fewer defects in workmanship. These can be accomplished through the use of fine-tuned weld programs that offer consistency and repeatability.