How NOT to Stick Weld

Mastering stick welding (Shielded Metal Arc Welding or SMAW) is as much about knowing how NOT to Stick Weld as it is about following the right steps. Many welders, especially beginners, unknowingly form bad habits that limit their weld quality, cause frustration, or even lead to injury. This guide aims to identify and explain the most common stick welding mistakes so that you can avoid them entirely.

Stick Welding (SMAW) Basics

Before diving into errors, it’s helpful to briefly understand how stick welding works. In SMAW, an electric current flows through a consumable electrode, creating an arc that melts both the rod and the base metal. The electrode’s flux coating generates shielding gas and slag to protect the weld.

But as simple as it sounds, many variables must be dialed in correctly—otherwise, you’ll get slag inclusions, undercutting, porosity, cracking, or worse.

Poor Electrode Selection

Using the Wrong Type of Rod for the Job

Stick welding requires careful electrode selection. Using a 6011 rod on thin sheet metal, for instance, can blow holes clean through due to its aggressive arc. On the other hand, using E7018 on dirty or rusted metal will almost certainly cause porosity and weak fusion.

Each rod type is designed for specific scenarios—E6010 for root passes and penetration, E7018 for clean structural work. Know your material and application, then choose accordingly.

Choosing Incompatible Electrodes for the Power Source

Electrodes have polarity requirements. E7018 runs best on DCEP, while E6011 is more forgiving and can run on AC. Trying to burn an electrode on the wrong polarity often leads to a wandering arc or rod sticking. Always check the manufacturer’s chart for polarity compatibility.

Incorrect Polarity Settings

Effects of Reverse vs. Straight Polarity

Reverse polarity (DCEP) directs more heat into the base metal, improving penetration. Straight polarity (DCEN) pushes heat into the electrode, giving a softer arc. Misunderstanding these can cause weld failure. For example, running E7018 on DCEN will yield poor fusion and low deposition.

When to Use AC, DCEN, and DCEP Correctly

Stick welders must set polarity based on the rod. AC is used when welding with basic transformer machines or when dealing with magnetized steel. DCEP is standard for most general-purpose rods like 6013 or 7018. DCEN is rarely used in stick welding unless specified.

Faulty Amperage Settings

Running Too Hot or Too Cold

One of the quickest ways to sabotage a weld is by running the wrong amperage. Too cold, and the rod sticks or lacks penetration. Too hot, and you get excessive spatter, undercutting, or even burning through the workpiece.

Problems Caused by Too High Amperage

• Undercutting at the weld toe

• Loss of arc control

• Burn-through on thinner material

• Excessive smoke and spatter

Problems Caused by Too Low Amperage

• Electrode sticking to the base metal

• Poor fusion and penetration

• Weak, lumpy, inconsistent weld beads

Poor Arc Striking Technique

Scratching vs. Tapping – Which to Avoid and Why

Arc striking seems simple until you’ve scorched your base metal or broken a flux coating. While either tapping or scratching can start an arc, many beginners press too hard or drag too long. That overheats the rod tip or chips off flux, leading to arc instability.

Holding the Arc Too Far or Too Close

Arc length should roughly equal the rod’s diameter. Too far, and you get excessive spatter and loss of shielding. Too close, and the rod sticks or sputters. Inconsistent arc length causes voltage fluctuation and leads to erratic welds.

Bad Travel Speed and Angle

Too Fast – Incomplete Fusion

Moving too quickly means the weld pool can’t fuse properly with the base metal. This results in cold laps or shallow penetration. The bead might look okay but could break under stress.

Too Slow – Excessive Build-Up or Burn-Through

Going too slow causes the puddle to overheat, leading to sagging, excessive build-up, and even burning through thinner material. It also increases the risk of slag inclusion.

Inconsistent Electrode Angle

A steady 10–15° drag angle is standard for most stick rods. Tilting side to side or changing angles mid-bead interrupts penetration and can cause irregular bead appearance.

Improper Electrode Manipulation

Unsteady Hands and Wavering Arc Length

Holding the rod steady is crucial. Jerky movement leads to uneven welds. Wavering arc length changes the arc voltage and causes porosity or inconsistent penetration.

Unnecessary Weaving or Erratic Movement

While weaving is necessary on wide joints or multipass welds, excessive weaving—especially on small joints—creates undercut, poor slag coverage, or cold laps.

Welding on Dirty or Contaminated Metal

Effects of Rust, Paint, Oil, and Moisture

Stick welding is somewhat forgiving, but not invincible. Surface contaminants create gas pockets, leading to porosity. Oil or paint can even cause toxic fumes. Always clean the weld zone with a grinder or wire brush before striking an arc.

How Contaminants Lead to Porosity and Slag Inclusions

Contaminants disrupt arc stability and shielding effectiveness. They create tiny air pockets in the weld, which harden as internal bubbles or slag traps, weakening the structure.

Ignoring Joint Fit-Up and Preparation

Welding Over Gaps or Poor Edge Prep

No matter how good your technique, you can’t weld over wide gaps or unprepared edges. Fit-up directly affects penetration and joint integrity. Always bevel thicker plates and ensure tight, even joints.

Skipping Preheat or Not Clamping Properly

On thicker materials or certain alloys, preheating is necessary to avoid cracking. Similarly, unrestrained parts may pull apart from thermal expansion. Use clamps and jigs to keep everything in place.

Slag Removal and Cleaning Between Passes

How Slag Traps Cause Weak Welds

Failing to chip away slag after a pass traps impurities in subsequent layers. This leads to inclusions, lack of fusion, and eventual weld failure.

Importance of Chipping and Wire Brushing Between Passes

Use a slag hammer and wire brush religiously between each pass. Especially when using rods like E7018, which produce a heavy slag coating, thorough cleaning is essential for weld integrity.

Conclusion

Stick welding is a powerful and versatile process—but also unforgiving when mistakes are made. By understanding and avoiding the most common pitfalls—from poor rod choice to contaminated surfaces—you build a foundation of good habits. Welding correctly takes time, but welding incorrectly costs time, safety, and structural integrity. Recognizing How NOT to Stick Weld is the first step toward becoming a skilled welder.