Striking an Arc and Maintaining Arc Length with a Portable Stick Welder

Once your portable stick welder is set up with a fresh electrode gripped in the stinger’s jaws, the two pieces of base metal have been properly prepared with whatever grinding, polishing, and scrubbing with metal conditioner is necessary to provide a paint- and rust-free welding surface, and you have donned your welding clothes, your gloves, your respirator, and your auto-darkening helmet, it is time to strike an arc from your electrode and start welding.

Striking an arc is a brief, fairly easy process which will become even easier as you get the hang of it. The process is quite similar to striking a match – sliding the tip of the stick electrode across the metal’s surface until you see the telltale gleam of a kindling arc, and then lifting the electrode smoothly away from the metal to draw out the arc into the air. The length of the arc should be a fraction under the diameter of the welding rod – so if you are using a 3/8” rod, then the maximum distance the end of the electrode can be from the workpiece is slightly under 3/8”.

Sometimes, the tip of the stick electrode will adhere to the metal rather than lifting away. In this case, you have the choice between wiggling the stinger back and forth or twisting it to free the electrode, or opening the stinger jaws so that the electrode will fall clear and can be replaced between the jaws for another attempt at striking the arc. Repeated failures to strike a successful arc probably indicate excessively low amperage which should be corrected gradually upwards.

Interestingly, an excessively short arc – with the tip of the electrode too close to the surface – does not cause excessive melting, as the inexperienced welder might logically suppose, since generally, the closer a heat source is to an object, the more heat it will transmit to that object. In arc welding, however, a short arc will make the welding area cooler, and penetration will be very poor, leading to filler metal lumped up above the base metal’s surface and a very shallow, weak weld.

This is not as mysterious as it might appear – the heat is supplied not by the electricity itself, but by the air’s resistance to it, causing electric energy to transform into heat energy. When there is a too-thin layer of air between the stick electrode’s tip and the base metal, there is little resistance to the electricity and only sparse conversion into heat energy occurs.

Longer arcs, on the other hand, are not necessarily much hotter than a properly-adjusted arc, because there is a peak conversion from electricity to heat that cannot be exceeded without changing the resistor from air to something else. The arc will become unpredictable and start to wander this way and that, out of your control, however, deforming the weld, and the filler metal will reach the surface as droplets that will congeal on the surface into tiny, gleaming nodules.

Clearly, then, the first imperative after striking your arc is to get it to the proper distance from the workpiece and keep it there throughout the weld – a process requiring concentration, a steady hand, and, of course, practice.