FCAW NC II common mistakes
FCAW NC II · Understand the traps and how to avoid them.
Using the wrong shade of welding helmet or failing to wear appropriate PPE for the specific FCAW task (e.g., not using a respirator when welding in a confined space or with fume-generating materials).
Candidates often underestimate the intensity of the FCAW arc and the volume of fumes produced, or they rely on general PPE without considering the specific hazards of the job.
What to do instead
Always refer to the site's welding procedure specification (WPS) and safety data sheets (SDS) for PPE requirements. For FCAW, use a minimum shade 10 (or higher for higher currents) and ensure proper ventilation or respiratory protection when welding in confined spaces or on metals with coatings.
Inspecting and maintaining the welding gun and liner only after a problem occurs, rather than following a scheduled maintenance routine.
Candidates may focus on the welding task itself and neglect preventive maintenance, leading to wire feed issues, porosity, and inconsistent welds.
What to do instead
Implement a daily and weekly maintenance checklist: clean the gun nozzle and contact tip, check the liner for wear and debris, inspect the drive rolls for proper tension and alignment, and replace worn parts according to the manufacturer's recommendations.
Misreading welding symbols on drawings, such as confusing the arrow side and other side, or misinterpreting the size and length of the weld.
Candidates may not have practiced enough with standard welding symbols (AWS A2.4) and may rush through drawing interpretation, leading to incorrect weld placement or sizing.
What to do instead
Study the standard welding symbol chart and practice interpreting symbols on sample drawings. Always double-check the arrow side (below the reference line) and other side (above the reference line) and verify dimensions with the WPS.
Incorrectly preparing the joint, such as failing to clean the base metal, not beveling at the correct angle, or not maintaining the proper root gap and alignment.
Candidates may skip cleaning steps or assume that the fit-up is correct without measuring, leading to lack of fusion, incomplete penetration, or distortion.
What to do instead
Follow the WPS for joint preparation: clean the surfaces to bare metal, use a bevel gauge to check angles, and use measuring tools (e.g., taper gauge, feeler gauge) to verify root gap and alignment before welding.
Setting the voltage and wire feed speed (WFS) arbitrarily without referring to the WPS or performing a test weld on scrap material.
Candidates may rely on guesswork or memory from previous jobs, not realizing that different materials, thicknesses, and positions require specific parameters.
What to do instead
Always consult the WPS for the correct parameters. If no WPS is available, perform a trial weld on scrap of the same material and thickness, adjust parameters to achieve a smooth arc and proper bead shape, and record the settings.
Using the wrong travel angle or work angle, or maintaining an incorrect travel speed, leading to poor bead shape, slag inclusion, or lack of fusion.
Candidates may not understand the effect of angle and speed on weld quality, or they may become fatigued and lose consistency.
What to do instead
Practice maintaining a consistent travel angle (typically 5-15 degrees push or drag, depending on the electrode) and work angle (45 degrees for fillet welds). Use a weaving technique only if specified. Monitor the weld pool and adjust speed to maintain a consistent bead width.
Failing to identify weld defects such as porosity, slag inclusion, or incomplete fusion during visual inspection, or not using proper inspection tools.
Candidates may lack training in visual inspection criteria or may not know how to use a weld gauge or magnifying glass effectively.
What to do instead
Study the acceptance criteria in the applicable code (e.g., AWS D1.1). Use a weld gauge to measure bead size, undercut, and reinforcement. Perform visual inspection under adequate lighting and with magnification if needed. Document any defects and rework as necessary.
Skipping post-weld cleaning, such as not removing slag or spatter, or not performing post-weld heat treatment when required.
Candidates may consider the job done once welding is complete, forgetting that finishing and documentation are part of the process.
What to do instead
Follow the WPS for post-weld operations: clean the weld with a chipping hammer and wire brush, remove spatter, and perform any required heat treatment. Complete all documentation, including weld maps and inspection reports.
Not participating in continuous improvement activities, such as failing to report recurring defects or suggest process improvements.
Candidates may see quality as solely the inspector's responsibility or may not feel empowered to suggest changes.
What to do instead
Actively participate in quality meetings, report any recurring issues to the supervisor, and suggest improvements to procedures or tools. Keep a log of defects and their causes to identify trends.
Ignoring environmental protection measures, such as improper disposal of welding waste (e.g., used electrodes, slag, packaging) or not minimizing fume and noise emissions.
Candidates may focus on safety and quality but overlook environmental impacts, or they may not be aware of local regulations.
What to do instead
Follow the site's environmental management plan: segregate waste for recycling, dispose of hazardous materials properly, use fume extraction systems, and minimize noise by using barriers or scheduling noisy work at appropriate times.