Welding Preparation and Techniques

3. Diameter of electrode tip.

• It is necessary to check the diameter of the electrode in order to obtain the necessary welding strength. Before beginning work ensure that the diameter of the tip (D) is adequate for the thickness of the metal sheet. Remove all traces of burns and foreign bodies from the tips of the electrodes.

D = Diameter of the electrode tip

t = Plate thickness

Condition and preparation of the panels to be welded. The presence of discontinuity, paint, rust or dust on panel edges prevents the flow of electricity and thus reduces welding strength. Before beginning welding, check the condition of the mating surfaces and make any adjustment necessary.

1. Gaps between mating surfaces.

• Even a slight gap between the surfaces to be welded reduces the intensity of the flow of electricity resulting in welds that will be too small or weak. Before welding join the surfaces and, when necessary, secure them with a clamp.

a. Incorrect

b. Correct

2. Welding of metal surfaces.

• To obtain the best results prepare the surfaces to be welded by removing all traces of impurities and foreign bodies (paint, dust, rust).