How To Arc Weld: 8 Steps

How to arc weld: This article shows you the steps for setting up and getting the arc for arc welding. But this will not apply to every type of welder. Check your welder user manual and double check with your instructor or a professional welder before you try these steps.

The basic steps of arc welding consist of creating an electric arc between the metal and the electrode (the electrode is a stick or wire that conducts the current but also melts and supplies the filler metal), otherwise known as striking the arc, moving the arc to create a bead (which is the melting metal combined with the metal from the melting electrode; this is used to fill the space between the two pieces being welded), shaping the bead (this is done by weaving the torch in a back and forth motion, figure eight motion, or zigzag motion), and removing the slag (the melted electrode filler material) from the surface of the weld bead between passes. The details of these steps, as well as additional procedures, are as follows:

How to arc weld part one:

Prepare the metal - the metal should e cleaned, and, if necessary, prep welded (this consists of creating a beveled edge on the sides of the two pieces to be joined; this ensures deep enough penetration of the weld arc to melt both sides).

How to arc weld part two:

Clamp the two pieces of metal to be welded together.

How to arc weld part three:

Select the correct amperage and rod for the type of metal being welded.

How to arc weld part four:

Attach the power source (either AC or DC, depending on the electrode type - DC is most commonly used for most electrode types, although some electrode types will work only with DC - and thickness of the base metal - sheet metal works best with DC since it is easier to strike and maintain the arc at low currents -, the distance from the power source to the metal - a long distance will work best with an AC current - , the welding position - DC is best used for overhead and vertical positions - , and if welding in corners, when AC is best used) with a work cable to the base metal, and with a "hot" cable to the electrode. If using a DC power source, determine if you are going to use positive or negative electrode polarity, or straight or reverse polarity; these factors will determine the depth of penetration and rate of burn-off.

How to arc weld part five:

Select the correct amperage; too much amperage will create a result that is pitted or cratered, or metal that is melted or pulled away; too little amperage will make it hard to strike the arc or maintain the arc.

How to arc weld part five:

Determine the position of the rod/angle of travel - for a vertical welding use a push or forehand technique and tilt the top of the rod at a 15 degree angle in the opposite direction of the traveling path; if welding in a flat, overhead, or horizontal position use a pull or drag position, holding the rod in a straight perpendicular position tilted at a 10 to 15 degree angle in the direction of the traveling path.

How to arc weld part six:

Turn on the machine and prepare to strike the arc - select the point where you wish to begin the weld, and then tap the tip of the electrode (which should be held in your dominant hand) against the metal at this point, immediately withdrawing it away about ¼ inch after to avoid having it stick to the metal (if it sticks you may wish to try gripping the clamp on the rod and pulling that away). There are a number of methods used to strike the arc, the first being the jab method, where you position the electrode about ½ inch away from the metal, and then jab the metal with a poking motion, immediately withdrawing after. The second method is the scratch or strike method, which is similar to striking a match; the electrode rod is considered to be the match stick and the metal the sandpaper and is used to strike the metal. Pull back slightly when the arc occurs. If you hold the gap between the tip of the electrode and the metal steady a continuous arc should form (the gap is at the correct distance when a sizzling or crackling sound is heard, too far when a popping sound is heard, and too close when there is little or no noise at all).

How to arc weld part seven:

Once the arc is formed you must immediately feed the electrode into it; begin moving along the path you want to weld, all the while maintaining a consistent speed, staying in line with the path, and keeping a consistent arc (if the electrode sticks, grip the clamp on the rod and pull away; if the arc disappears, stop the process and clean the slag from the metal where you welding).

How to arc weld part eight:

Create the shape of the bead (the deposit of melted metal that joins the two pieces that you are welding together) by moving the electrode either in a slow, straight line or a zigzag motion; a slower motion will create a deeper weld, while a zigzag motion will create a wider bead, usually more preferred since you can fill more of the weld in a single pass and create a stronger and cleaner weld. Note, however, that this is necessary for thicker steels and metals; thinner metals ¼ inch or thinner usually require a straight line and smaller bead.

How to arc weld part nine:

Adjust the speed correspondingly to create a wider bead with shallow penetration (slower speeds).

Clean any slag off of the weld.