The Technology

Of the three welding systems I tested, the PUK 2 and Mini Pulse III use similar pulse-arc technologies. An arc is formed between a non-consumable tungsten electrode and the metal being welded, forming a molten pool. If filler material is used, it is fed separately into the molten pool. The use of an argon shielding gas can considerably reduce oxidation and facilitates a smoother transfer of filler material.

This is very similar to GTAW (Gas Tungsten Arc Welding), which is often referred to as TIG (Tungsten Inert Gas) welding—the method of choice in steel fabrication shops where high quality precision welding is required. The biggest difference between the pulse-arc systems I tested and TIG welders is that the latter use a continuous arc, allowing for an uninterrupted seam as the electrode is moved across the weld interface. Pulse-arc welders do just what they say—pulse an arc in a burst of electrical energy.

Laser welders, on the other hand, use Nd:YAG laser beams generated by flash lamps. Although a laser welder’s high pulse frequency may lead you to believe that it produces a continuous weld seam, it too is actually producing single, overlapping spot welds just like the pulse-arc welders, only much more rapidly.