A sharpened 1mm tungsten electrode is used for this application. The stylus is removed from the microscope assembly and used in a hand-held manner for easier access to the difficult to reach part geometry.
The above welds were performed by the Orion Pulse 150i set to20ws energy in Micro Mode It is helpful to “aim” the electrode at the joint where the tab meets the steel. The flatter and closer together you can make the mating surfaces, the easier it is to achieve good welds. The blackening is caused by zinc content being burned out during the weld and can be removed easily using a glass brush or other soft abrasive.
The Orion Pulse 150i is an ideal solution for welding the brass tabs to the steel plate. Pulse arc technology is very useful for joining dissimilar metals such as these samples. The touch screen user interface makes it easy for operators to quickly fine tune energy settings and find successful weld parameters.