Common Types of Welding (FCAW, GMAW, GTAW, SMAW, SAW)

When I first started welding, one of the biggest challenges I ran into wasn’t striking an arc — it was figuring out which process to use. Should I go with MIG for speed, TIG for precision, stick welding for versatility, or flux-core for outdoor jobs where wind blows shielding gas away? Like most welders, I quickly learned that understanding the common types of welding — FCAW, GMAW, GTAW, SMAW, and SAW — is just as important as mastering filler rods, joint prep, arc control, or knowing how metal thickness affects penetration.

The wrong choice can mean wasted gas, poor bead quality, or worse — a weld that fails under stress. Whether you’re working on stainless welding for a food-grade project or running structural passes on heavy steel, picking the right process matters for safety, strength, and cost-efficiency. In this guide, I’ll break down each method in plain language, compare MIG vs TIG, and share hard-earned tips that will save you time and frustration in the shop.

Photo by researchgate

What Is FCAW and When Should You Use It?

Flux-Cored Arc Welding (FCAW) is like the rugged cousin of MIG welding. It uses a tubular wire filled with flux, which creates a shield around the weld pool to protect it from the atmosphere. You’ve got two flavors: self-shielded (FCAW-S) and gas-shielded (FCAW-G). The self-shielded version is a lifesaver outdoors since it doesn’t need an external gas tank, making it ideal for windy job sites like bridge construction or shipbuilding.

I remember my first FCAW job on a rusty steel beam in a shipyard. The wind was howling, but FCAW-S didn’t care—it laid down a solid bead without a hitch. The high deposition rate (think 3–20 pounds of metal per hour) means you’re getting a lot of weld fast, perfect for thick materials like carbon steel or heavy equipment repairs. But here’s the catch: it produces a ton of spatter and slag, so cleanup is a chore, and the smoke can be intense. Always wear a good respirator.

How FCAW Works

You feed a continuous flux-cored wire through a welding gun, and an electric arc melts both the wire and the base metal. The flux inside the wire burns, forming a gas shield (or slag in FCAW-S) to protect the weld. It’s semi-automatic, so you control the gun, but the wire feeds automatically.

Practical Tips for FCAW

Machine Settings: Start with a voltage around 22–28V and wire feed speed of 300–400 inches per minute for 0.035-inch wire. Adjust based on material thickness.

Joint Prep: FCAW is forgiving, so light rust or dirt isn’t a dealbreaker, but clean the surface for best results.

Common Mistake: Setting the wire feed too fast causes spatter. Dial it back if you see excessive popping.

Filler Compatibility: Use E71T-1 for gas-shielded FCAW on carbon steel, or E71T-11 for self-shielded welds.

When to Use FCAW

Choose FCAW for thick steel, outdoor work, or when speed matters. It’s not great for thin metals (under 20 gauge) or aluminum, as it can burn through. Think shipyards, heavy machinery, or structural steel.

GMAW: The Go-To for Speed and Versatility

Gas Metal Arc Welding (GMAW), or MIG welding, is the darling of automotive shops and fabrication floors. It uses a solid wire electrode and a shielding gas (usually argon, CO2, or a mix) to create clean, fast welds.

It’s beginner-friendly, versatile, and works on everything from mild steel to aluminum. I’ve used GMAW to weld car frames and stainless steel exhausts, and it’s a dream for its speed and minimal cleanup.

The downside? You need a gas tank, which makes it less portable, and wind can disrupt the shielding gas, so it’s better indoors. Also, gas costs can add up, especially if you’re using argon for aluminum.

How GMAW Works

A continuous wire feeds through a gun, and an arc forms between the wire and the metal. The shielding gas flows from the nozzle, protecting the weld pool from oxygen and nitrogen. You can tweak the transfer mode (short-arc, spray, or globular) for different effects.

Practical Tips for GMAW

• Machine Settings: For 1/8-inch steel, try 18–22V and 150–200 inches per minute wire speed with 0.030-inch wire. Use 75% argon/25% CO2 for steel.
• Joint Prep: Cleanliness is key. Remove oil, rust, or paint for a smooth arc.
• Common Mistake: Incorrect gas flow (10–20 cubic feet per hour is ideal) can cause porosity. Check your regulator.
• Filler Compatibility: ER70S-6 wire is great for steel; ER4043 works for aluminum.

When to Use GMAW

GMAW shines for thin to medium materials, like sheet metal or automotive parts. It’s fast, clean, and ideal for indoor fabrication, but avoid it in windy conditions unless you’ve got a sheltered setup.

GTAW: Precision for the Picky Welder

Gas Tungsten Arc Welding (GTAW), or TIG welding, is the artist’s choice. It uses a non-consumable tungsten electrode and a shielding gas (usually argon) to produce pristine welds. You manually feed a filler rod, which demands skill but gives unmatched control. I’ve TIG-welded aluminum bike frames and stainless steel food-grade piping, and the results are gorgeous—clean, strong, and precise.

The trade-off is speed. TIG is slow, and it’s not for beginners. You need steady hands and a good eye. It’s also pricier due to gas and tungsten costs, but for high-stakes jobs like aerospace or medical equipment, it’s worth it.

How GTAW Works

The tungsten electrode creates an arc that melts the base metal. You dip a filler rod into the weld pool while shielding gas protects it. It’s all about finesse—think of it as painting with molten metal.

Practical Tips for GTAW

• Machine Settings: Use 100–150 amps for 1/8-inch aluminum with AC current. DCEN works for steel.
• Joint Prep: Surfaces must be spotless. Use a wire brush or grinder to remove oxides.
• Common Mistake: Touching the tungsten to the workpiece contaminates it. Grind it clean or replace it.
• Filler Compatibility: Use ER308L for stainless steel, ER4043 for aluminum, and match filler to base metal.

When to Use GTAW

TIG is perfect for thin materials, non-ferrous metals like aluminum or titanium, or when aesthetics matter. It’s common in aerospace, art, and high-end fabrication.

SMAW: The Old-School Workhorse

Shielded Metal Arc Welding (SMAW), or stick welding, is the granddaddy of welding. It uses a flux-coated electrode (the “stick”) that melts to form the weld and a slag shield. It’s simple, portable, and works on dirty or rusty surfaces, making it a favorite for construction and repairs. I’ve stick-welded rebar on a muddy site and patched farm equipment in the rain—it’s tough as nails.

The downside? Slag cleanup is a pain, and the welds aren’t as pretty as TIG or MIG. It’s also slower, as you stop to swap rods, and it’s prone to porosity if you’re not careful.

How SMAW Works

An electric current forms an arc between the electrode and the metal. The flux coating burns, creating a gas and slag to shield the weld. You replace the electrode as it burns down.

Practical Tips for SMAW

• Machine Settings: For 1/8-inch E6010 electrodes, set 80–120 amps. Adjust higher for thicker metal.
• Joint Prep: It’s forgiving, but a quick grind helps. Remove heavy rust for better penetration.
• Common Mistake: Running too hot burns through thin metal. Start low and creep up.
• Filler Compatibility: E6010 for deep penetration, E7018 for cleaner welds on steel.

When to Use SMAW

Stick welding is great for outdoor repairs, structural work, or when equipment needs to be portable. It’s not ideal for thin metals or high-precision jobs.

SAW: The Heavy-Duty Automaton

Submerged Arc Welding (SAW) is the industrial beast, used for thick materials in automated setups. It buries the arc under a layer of granular flux, producing deep, strong welds with minimal spatter.

I’ve seen SAW in action on massive pressure vessels and ship hulls—its efficiency is unreal. But it’s not for small shops or manual work; it’s bulky, expensive, and best for flat, long welds.

How SAW Works

A continuous wire feeds into the weld zone, covered by flux powder. The arc melts the wire and base metal, and the flux shields the weld while forming a slag. It’s usually automated, with the machine moving along the joint.

Practical Tips for SAW

• Machine Settings: Use 400–600 amps for thick steel, with 25–35V. Wire speed depends on the setup.
• Joint Prep: Ensure clean, flat surfaces. Misalignment kills SAW quality.
• Common Mistake: Too much flux buries the arc, causing defects. Keep a consistent layer.
• Filler Compatibility: Match wire and flux to the base metal (e.g., F7A2-EM12K for carbon steel).

When to Use SAW

SAW is for high-volume, thick-material jobs like pipelines, tanks, or heavy manufacturing. It’s not practical for small-scale or positional welding.

Comparing the Five Welding Processes

Here’s a quick comparison to help you choose:

Process	Best For	Pros	Cons	Typical Materials
FCAW	Thick steel, outdoor work	High deposition, works on dirty surfaces, no gas needed (FCAW-S)	Spatter, slag cleanup, smoky	Carbon steel, stainless steel
GMAW (MIG)	Thin to medium metals, indoor	Fast, clean, beginner-friendly	Gas costs, wind-sensitive	Steel, aluminum, stainless
GTAW (TIG)	Thin metals, precision work	High-quality welds, versatile	Slow, skill-intensive, costly	Aluminum, titanium, stainless
SMAW (Stick)	Outdoor repairs, structural	Portable, forgiving, cheap	Slag cleanup, lower quality	Steel, cast iron
SAW	Thick materials, automated	Deep penetration, efficient	Bulky, limited positions	Carbon steel, heavy alloys

Safety First: Protecting Yourself and Your Work

Welding is hot, bright, and potentially hazardous. I learned this the hard way when I skipped my helmet’s auto-darkening lens one day and ended up with arc eye—trust me, it’s like sand in your eyes for hours.

Always wear a welding helmet with the right shade (10–13 for most processes), fire-resistant gloves, and a jacket. Use a respirator for FCAW or SAW to avoid fume inhalation. Keep your workspace clear of flammables, and ensure good ventilation, especially indoors with GMAW or GTAW.

For equipment, check cables for fraying, ensure your ground clamp is secure, and never weld wet surfaces—electrocution isn’t a joke. Follow OSHA and AWS safety guidelines, especially on job sites.

Step-by-Step Guide to Starting a Weld

Let’s walk through a basic weld setup, adaptable to FCAW, GMAW, GTAW, or SMAW:

1. Choose Your Process: Match the method to your material and environment (e.g., FCAW for outdoor steel, TIG for aluminum).
2. Prep the Metal: Grind or brush off rust, paint, or oil. For TIG, degrease thoroughly.
3. Select Filler: Pick a rod or wire that matches your base metal (e.g., ER70S-6 for GMAW on steel).
4. Set Up the Machine: Dial in voltage, amperage, and wire speed based on material thickness and process.
5. Test the Arc: Run a practice bead on scrap metal to check settings.
6. Weld the Joint: Maintain a steady hand, consistent angle (15–20° for most processes), and travel speed.
7. Clean Up: Chip slag (FCAW, SMAW) or inspect for defects like porosity.
8. Inspect: Check for cracks or incomplete fusion. Grind and reweld if needed.

Choosing the Right Process for Your Project

The job dictates the process. For a DIY gate repair in your backyard, SMAW or FCAW-S is quick and forgiving. Building a custom aluminum bike frame? GTAW is your best bet for precision. Working in a fab shop on stainless steel tanks? GMAW or FCAW-G gets it done fast.

For massive industrial jobs, SAW’s automation saves time. Consider material thickness, environment, and your skill level. If you’re new, start with GMAW—it’s forgiving and fast to learn.

Common Mistakes and How to Fix Them

• Porosity (holes in the weld): Caused by dirty surfaces or wrong gas flow. Clean thoroughly and check your regulator.
• Burn-Through: Too much heat on thin metal. Lower amps or increase travel speed.
• Spatter: Common in FCAW or GMAW. Adjust voltage or use anti-spatter spray.
• Weak Welds: Poor penetration from low amps or bad technique. Increase power and practice your angle.

Key Takeaways for Better Welding

You’re now armed with the knowledge to pick the right welding process for any job. FCAW is your outdoor warrior, GMAW is the speedy all-rounder, GTAW is the precision artist, SMAW is the rugged classic, and SAW is the industrial powerhouse. Match your process to the material, environment, and project demands, and you’ll lay down strong, reliable welds every time.

FAQ

What’s the easiest welding process for beginners?

GMAW (MIG) is the easiest to learn due to its automatic wire feed and forgiving nature. Start with mild steel and a 75% argon/25% CO2 mix for smooth results.

Can I use FCAW for thin metals?

FCAW isn’t ideal for metals thinner than 20 gauge—it’s too hot and can burn through. Stick with GMAW or GTAW for thin materials like sheet metal.

Why does my weld have so much spatter?

Spatter comes from high voltage, fast wire speed, or dirty surfaces. Lower your voltage, clean the metal, and use anti-spatter spray for cleaner welds.

Is TIG welding worth the effort for hobbyists?

Yes, if you’re working on aluminum, stainless, or projects needing clean, precise welds. It takes practice, but the results are stunning for custom work.

What safety gear do I really need for welding?

At minimum, get a welding helmet (shade 10–13), fire-resistant gloves, a jacket, and steel-toe boots. For FCAW or SAW, add a respirator to protect against fumes.