Metal Mastery Slides Industrial Arts Series
Metal Mastery
Essential Skills in SMAW, GMAW, and GTAW Processes
SMAW: Safety First
Essential PPE
• Auto-Darkening Helmet (Shade 10-13)
• Flame-Resistant Jacket (Leather/Cotton)
• Gauntlet-style Leather Gloves
• Steel-Toe Boots (No Laces/Covered)
Hazard Awareness
• Arc Flash: UV damage to eyes
• Fumes: Requires proper ventilation
• Electric Shock: Inspect cables for nicks
SMAW: The Stick Setup
Step 1
Grounding
Ensure a clean metal surface for the work clamp. Poor grounding leads to arc instability.
Step 2
Electrode Selection
Common: 6010 (Deep penetration), 6011, or 7018 (Low hydrogen/Strong).
"Striking the Match"
Unlike MIG, Stick requires a "strike" or "tap" to initiate the arc. Maintain an arc length equal to the electrode diameter.
CLANS
The Memory Tool
C - Current (Amperage)
L - Length of Arc
A - Angle of Electrode
N - Neighborhood (Speed)
S - Selection (Electrode)
GMAW Techniques
The "Point and Shoot"
Constant voltage process where wire is automatically fed through a gun.
Settings
• Wire Feed Speed (WFS)
• Voltage (Heat)
• Shielding Gas Flow
Shielding Gas
75% Argon / 25% CO2 (C25) is the industry standard for steel.
Gun Movement
PUSH
Better visibility, shallower penetration. "Leading" the puddle.
PULL
"Dragging" the puddle. Greater penetration, narrower bead.
GTAW: The Precision Process
Highest control, highest difficulty.
The Three-Point Coordination
1 Torch Hand: Maintains precise arc gap and travel.
2 Dabbing Hand: Feeds filler rod into the front of the puddle.
3 Foot Pedal: Real-time control of amperage (heat).
Tungsten Electrode
Non-consumable. Must be ground to a fine point for DC (Steel) or balled/tapered for AC (Aluminum).
Shielding Gas
100% Argon. Provides maximum protection for the weld pool.
Pro Tip: "Walking the Cup"
A technique used on pipes where the ceramic nozzle is rested and rocked on the metal for a consistent weave.
Inspection QC
Is your weld structurally sound?
🕳️
Porosity
"Swiss Cheese"
Trapped gas bubbles. Caused by wind, lack of gas, or dirty metal.
📉
Undercut
"Edge Groove"
A groove melted into base metal not filled by weld. Caused by high heat or bad angle.
⛰️
Slag Inclusion
"Stick's Enemy"
Non-metallic pieces trapped in weld. Result of poor cleaning between passes.
❌
Lack of Fusion
"Cold Lap"
Weld metal doesn't fuse to base metal. Caused by low heat or travel speed too high.
The Path to Pro
Industrial & Pipeline
Building structural steel, bridges, and oil/gas pipelines. High demand, often involves travel and outdoor work.
Aerospace & Specialized
High-precision TIG welding on exotic metals. Clean-room environments with very high pay for specialized skills.
Marine & Underwater
Shipbuilding and underwater repair. Requires commercial diving certification and top-tier welding ability.
Certification Matters
AWS
American Welding Society
The gold standard for "Certified Welder" credentials.
UA
Union Apprenticeships
Earn while you learn. Unions offer training, benefits, and job security.
Ready to Strike?
Welding is 10% theory and 90% muscle memory. Safety is the foundation; precision is the goal.
Safety
Eyes, Lungs, Skin. Protect them daily.
Process
Stick for field. MIG for production. TIG for precision.
Quality
Inspect every bead. Learn from your defects.
Welding Safety Checklist Pre-Strike Checklist
SMAW • GMAW • GTAW Safety Standards
Student:
Date:
Phase 1: Personal Protection (PPE)
Welding Helmet
Auto-darkening; Shade 10-13; No cracks in lens.
Leather Gauntlets
Dry; No holes; Appropriate for the process (Stick/MIG/TIG).
FR Jacket / Apron
Full sleeves; Buttoned/Zipped up; No frayed edges.
Safety Glasses
Z87+ rated; To be worn under the helmet at all times.
Leather Work Boots
Steel/composite toe; Laces covered or non-existent.
Hearing Protection
Earplugs or muffs if grinding or in loud shop areas.
Phase 2: Booth & Surroundings
Clear Workspace
Floor is dry and free of trip hazards (cables, scrap metal). No flammable liquids or rags within 35 feet.
Ventilation Check
Fume extractor is positioned 6-10 inches from the weld zone and turned on. Airflow is moving away from the face.
Flash Shielding
Welding curtains are closed to protect classmates from arc flash UV rays.
Phase 3: Machine & Leads
SMAW / GMAW Setup
Cables inspected for nicks, burns, or exposed copper.
Work clamp (ground) is tight on clean, unpainted metal.
Gas cylinder (GMAW/GTAW) is chained securely.
The "Golden Rule"
Never change the polarity or amperage on a machine while an arc is being struck. This can damage the internal components of the welder.
Always yell "ARC!" before striking.
Instructor Verification
Safety check must be witnessed before machine activation.
Defect Detective Worksheet Defect Detective
Visual Inspection & Quality Control
Inspector:
Assignment Brief
A visual inspector has identified four critical weld failures in the shop. For each case study below, identify the Defect Name , the likely Cause , and the Cure (how to prevent it next time).
01
🕳️
Surface View
Defect Name
Suspected Cause
Recommended Cure
02
📉
Toes of the Weld
Defect Name
Suspected Cause
Recommended Cure
03
⛰️
Inside the Bead
Defect Name
Suspected Cause
Recommended Cure
04
❌
Root / Face View
Defect Name
Suspected Cause
Recommended Cure
The "Why" Behind the Quality
Explain why identifying defects like Undercut and Porosity is critical for structural welding projects (such as bridges or high-rise buildings). What are the potential real-world consequences of these defects?
Defect Detective Answer Key Detective Key
Teacher Reference • Visual Inspection
Instructional Note
Students should focus on the technical terminology used in the Metal Mastery Slides. Acceptable answers may vary slightly in wording, but the core technical cause must be identified.
01
Defect Name
Porosity
Suspected Causes
• Improper gas flow / empty cylinder (MIG/TIG)
• Windy conditions blowing away shielding gas
• Contaminants (rust, oil, paint) on base metal
Recommended Cures
• Check flowmeter and regulator settings
• Set up welding screens to block drafts
• Use a grinder/wire brush to reach shiny metal
02
Defect Name
Undercut
Suspected Causes
• Amperage (current) is too high (too much heat)
• Travel speed is too high (not enough filler metal)
• Incorrect torch/electrode angle
Recommended Cures
• Dial back the machine voltage/amperage
• Slow down to allow the puddle to fill the edges
• Direct the arc more toward the heavier piece
03
Defect Name
Slag Inclusion
Suspected Causes
• Poor cleaning between multi-pass welds
• Improper electrode angle (trapping slag)
• Low heat (amperage)
Recommended Cures
• Use a chipping hammer and wire brush thoroughly
• Increase amperage to keep the puddle fluid
• Maintain a proper "drag" angle in SMAW
04
Defect Name
Lack of Fusion
Suspected Causes
• Low heat (amperage/voltage)
• Travel speed is too fast
• Arc directed poorly (hitting only one side)
Recommended Cures
• Increase heat settings for better penetration
• Slow down to allow the base metal to melt
• Ensure the arc stays on the "leading edge" of puddle
Analysis Question - Key Points
Structural failure can lead to property damage or loss of life. Defects create "stress risers" where cracks begin. In bridges, vibrations can cause a small undercut to grow into a catastrophic fracture.
Metal Mastery Slides Updated Industrial Arts Series
Metal Mastery
Professional Welding: SMAW, GMAW, and GTAW
Safety Priority
Essential PPE
Auto-Darkening Helmet
Flame-Resistant Jacket
Gauntlet Leather Gloves
Steel-Toe Work Boots
Critical Hazards
ARC FLASH
Severe UV damage to eyes and skin.
WELDING FUMES
Requires localized exhaust ventilation.
ELECTRIC SHOCK
Never weld in wet conditions or with frayed leads.
SMAW Setup
The Ground
Attach the work clamp to clean, bare metal for a steady arc.
The Electrode
Choose by metal type. 7018 for strength, 6010 for deep digging.
"Striking the Match"
Unlike other processes, Shielded Metal Arc Welding (SMAW) requires a physical strike or tap to start the arc.
CLANS
Technique Guide
Current • Length of Arc
Angle • Neighborhood (Speed)
Selection of Rod
GMAW Production
Gas Metal Arc
Continuous wire feed makes this the fastest production process in modern shops.
Control Variables
• WFS: Wire Feed Speed (Amperage)
• Voltage: Controls the heat of the arc
• Gas: Typically 75% Argon / 25% CO2
Movement Strategy
PUSH
Shallow penetration, wide bead. Better puddle visibility.
PULL
Deeper penetration, narrower bead. Used for thicker metals.
GTAW Precision
Three-Hand Coordination
1
THE TORCH
Maintains a needle-thin arc gap.
2
THE FILLER
Manual "dabbing" into the molten pool.
3
THE PEDAL
Precision heat control via your foot.
Tungsten Tip
Non-consumable electrode. Must be ground to a fine point for precision arcs.
Pure Argon
100% Argon gas for the cleanest, strongest weld beads possible.
Defect Detection
Visual QC - Part 1
🕳️
Porosity
Trapped gas bubbles in the weld. Like "Swiss Cheese." Usually caused by wind or dirty base metal.
Welding Teacher Guide Mastery Teacher Guide
Instructional Strategy & Facilitation
90 Minute Session
Learning Objectives
• Identify PPE requirements and safety hazards for arc welding processes.
• Differentiate between SMAW, GMAW, and GTAW setup and techniques.
• Diagnose common weld defects (Porosity, Undercut, Slag, Fusion).
• Explore diverse career pathways and industry certifications (AWS).
Preparation
Display Slides
Print Checklists
Print Worksheets
Setup Demo Station
Lesson Pacing
15 MIN
Safety Walkthrough
Slides 1-2 & Safety Checklist
Introduce PPE. Distribute the Welding Safety Checklist. Physically walk students through the shop to identify fume extractors, flash shields, and ground points.
35 MIN
Process Comparison & Demo
Slides 3-5
Cover SMAW, GMAW, and GTAW. Teacher Demo: Strike an arc in SMAW (CLANS) vs GMAW. Show the difference between "Push" and "Pull" beads.
25 MIN
Defect Detective Lab
Slides 6-7 & Worksheet
Display slides showing defects. Have students complete the Defect Detective Worksheet. If available, use actual scrap metal with real defects for hands-on inspection.
15 MIN
Careers & Wrap-Up
Slides 8-9
Discuss pay scales and specialized fields. Emphasize the AWS certification as the primary goal for entry-level employment.
Critical Thinking Prompts
1. "Why is SMAW still used on construction sites when GMAW is faster?" (Answer: Portability, no gas tank needed, works in wind).
2. "Which defect is the most dangerous in a bridge support?" (Answer: Undercut or Lack of Fusion - structural integrity).
Differentiation
Support: Provide a word bank for the Defect Detective Worksheet.
Extension: Have advanced students calculate approximate wire feed speed (WFS) requirements based on plate thickness.
