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Start With the Electrode, Not the Joint

Vertical stick welding is controlled mainly by electrode diameter, rod type, metal thickness, and whether you weld uphill or downhill. The amperage printed on a welding chart is a starting point, not a guaranteed setting. Vertical joints usually need slightly less heat than flat welds because molten metal wants to run downward.

For most structural or repair work, vertical-up welding gives better penetration and control. Vertical-down welding is faster and can work well on thin sheet, but it produces less penetration and is a poor choice for heavily loaded joints unless the procedure specifically allows it.

Use the range printed on the electrode package first. If you are buying rods, a general-purpose E6011 welding rod handles dirty steel and AC machines well, while E6013 is easier to run on clean, thin material. E7018 makes strong, low-hydrogen welds but requires cleaner steel, correct storage, and more disciplined technique.

Useful Starting Amperage Ranges

The following settings are practical starting points for vertical-up welding on mild steel. Adjust in small steps after making a short test bead on similar material. The exact range varies by manufacturer and power source.

For a first test, set the machine near the lower-middle part of the vertical range. A 3/32-inch rod at about 80 amps is a useful starting point for many vertical-up fillet welds. An 1/8-inch rod often starts around 100 to 110 amps. If the arc keeps going out or the rod sticks, increase amperage slightly or improve your arc length before assuming the machine is at fault.

Adjust for Material Thickness and Joint Fit-Up

Thin material cannot absorb much heat. On steel around 1/8 inch thick, a 3/32-inch electrode is usually easier to control than an 1/8-inch rod. Start around 65–75 amps with E6013 or 70–80 amps with E6011, and use short beads to prevent burn-through. A backing strip can help, but it changes heat flow and may hide lack of fusion.

For 1/4-inch plate, 3/32-inch rods are still useful for control, while 1/8-inch rods deposit metal faster. If the joint is beveled, has a root gap, or requires multiple passes, use a smaller rod for the root and a larger rod for fill passes when the joint allows it. Do not compensate for a poor fit-up simply by turning up the amperage. Excess heat can enlarge the gap, cause undercut, and make the puddle impossible to control.

On a fillet weld, excessive amperage makes the puddle sag and can wash away the vertical edge. Too little amperage produces a tall, narrow bead with poor fusion at one or both sides. The goal is a controlled puddle that wets both pieces without falling away from the joint.

Use Vertical-Up Technique to Control the Puddle

Hold the electrode roughly perpendicular to the joint, with a slight upward work angle if needed to keep the puddle from running ahead. Maintain a short arc—about the diameter of the electrode or less. A long arc increases spatter, weakens shielding, and makes the puddle hotter and less stable.

For a vertical-up fillet, use a small weave or tight triangular motion. Pause briefly at each sidewall and move quickly across the center. The pauses fuse the toes of the weld; the quick movement across the middle prevents the center from becoming too convex. Keep each bead narrow. Wide weaving puts too much molten metal in the joint at one time.

With E7018, a slight side-to-side motion or small “Christmas tree” pattern works well, but avoid whipping the rod. With E6010 or E6011, a controlled whip-and-pause technique may help produce a root pass, but excessive whipping can leave slag inclusions and uneven fusion. Chip and brush every pass before adding the next.

Recognize the Wrong Setting

If the rod sticks repeatedly, the arc sounds weak, or the bead is tall and rope-like, amperage may be too low. A dirty work clamp, long extension cord, undersized leads, or incorrect polarity can create similar symptoms. Check those items before raising the setting dramatically.

If the puddle falls, the bead is excessively wide, or the vertical edge is undercut, amperage is probably too high or your travel speed is too slow. Lower the setting by 5 to 10 amps, shorten the arc, and use a tighter weave. A crater that remains molten after you stop usually indicates excess heat for the joint.

Wormholes, visible porosity, and slag trapped along the sidewall are not fixed by amperage alone. Remove paint, rust, oil, and moisture; use the polarity recommended for the rod; and clean between passes. E7018 electrodes exposed to moisture can cause porosity and hydrogen-related cracking, so store them as directed. For occasional home repairs, E6011 or E6013 is often the cheaper and simpler option when the job does not require a low-hydrogen procedure.

Choose a Machine and Gear That Match the Work

A basic AC stick welder is adequate for many E6011 and E6013 jobs. An inverter stick welder is usually lighter and offers smoother low-amperage control, which matters on vertical thin-wall work. The cheaper transformer machine is fine if it has enough output, suitable leads, and stable power. Pay more for an inverter when portability, generator use, or precise adjustment is important—not merely because it is newer.

Use a properly shaded auto-darkening welding helmet with a clear viewing area, flame-resistant clothing, leather gloves, and safety boots. A helmet with a grinding mode is convenient, but a cheaper fixed-shade helmet is perfectly serviceable if it fits well and has a clean lens. Ventilate the area, remove flammable materials, and never weld on containers that may have held fuel or chemicals.

Make a test weld on scrap in the same position before welding the actual joint. Change only one variable at a time: amperage, travel speed, arc length, or rod angle. That approach makes the correct setting easier to find and prevents a vertical weld from becoming an expensive repair.