TIG Welding Cup Walking: The Complete Guide

Split the joint in half and weld each side from 6 o’clock up to 12 o’clock. Working uphill lets gravity pull the puddle slightly back into the joint instead of ahead of it, and it keeps your body in a stable position as the torch climbs. Many welders start a touch below 6 o’clock so the tie-in at the bottom is already established when the root begins.

3. Run the Root Pass

Lay the filler rod into the groove ahead of the cup rather than dabbing it in from the side. Start the arc, establish the puddle, and let the cup’s edges rock against the bevel while the rod sits in the leading edge of the pool. Keep the arc length short and constant — the tungsten should never change its distance from the work as the cup rolls.

4. Run the Fill Passes

For fill passes, make three-point contact: the two bevel walls plus the previous bead. With three points touching, the groove itself guides the torch, and your wrist only supplies the rocking force. Aim each pass slightly at the sidewall so it ties into the edges, and finish each fill just below the surface to leave room for a proper cap. On multi-pass work, keep your heat input steady rather than rushing a cold, wide pass — the same travel discipline covered in stainless tube welding procedure applies to carbon steel too.

5. Run the Cap Pass

The cap is where cup walking looks its best. Drop to a single point of contact on the finished weld face and let the cup pivot there while the tungsten sweeps across the width of the cap. Roll forward one step at a time, overlapping each step evenly, and watch the toes of the puddle rather than the tungsten. A consistent step width produces the stacked-dime appearance; a wandering step width produces lumps that need grinding.

6. Keep the Filler Rod Correct

Hold the rod at the leading edge of the puddle, roughly tangent to the pipe surface, with the tip staying inside the shielding gas envelope. If the rod pulls out of the gas, the molten tip oxidizes and drags contamination back into the weld.

7. Handle Amperage Without a Foot Pedal

Many pipe setups run a torch-mounted control or a remote-free machine. Set your amperage for the thickest section before you strike the arc, then control heat with travel speed and arc dwell: slow down where the joint is thick or open, and let the cup move faster over tight, well-supported areas. Adding a small pause at each tie-in point keeps the fusion consistent when you stop and restart.

8. Terminate the Arc Cleanly

At 12 o’clock, taper the arc off while adding a final dab of filler to fill the crater. Snapping the arc off at full amperage leaves a crater pipe, which is a rejectable defect. Hold position until post-flow gas has covered the hot weld — on stainless, keep shielding until the metal is no longer glowing.

The whole sequence rewards rhythm over speed. Weld the root conservatively, let the groove guide the fill, and save the precision for the cap. If you are also working in aerospace TIG welding environments, this same disciplined pass order is what code inspectors expect to see.

Walking vs. Wiggling vs. Freehand: Which TIG Technique Should You Use?

Ask ten pipe welders how they move a TIG torch and you’ll get three different answers, because there are three legitimate ways to run a GTAW pass: wiggling, walking, and freehanding. They aren’t competing religions. They’re tools, and the welders who stay employed are the ones who know which tool fits the joint in front of them.

The difference comes down to how the ceramic cup touches the work. In the wiggle, the cup rests on two points, usually the two bevel faces of a groove, and the wrist rocks the torch side to side. In the walk, the cup rolls across a single contact point like a wheel. In freehand, the cup never touches anything at all, and your hand carries the entire arc length.

Head-to-Head Comparison

Why the Wiggle Wins Grooves

When you’re sitting in an open root with a feathered land, two points of contact give you a built-in guide. The cup bridges the gap, the torch can’t drift sideways, and a small wrist flick side to side washes the puddle into both walls. That two-point stance also keeps arc length short and steady, which is exactly what a root needs. As WeldingTipsAndTricks explains, the wiggle is really a controlled oscillation, not a nervous shake, and its width should never exceed about one and a half times the diameter of your electrode.

Why the Walk Wins Caps

A cap sits on a convex surface, so there’s no groove to bridge. That’s where rolling the cup shines: the single contact point glides over the crown, travel speed stays even, and the result is the stacked-dime look that inspectors associate with consistent rhythm. Walking is also faster than wiggling over long runs, which is why production pipe shops favor it. The technique’s origins lie in stainless tube work, as The Fabricator’s tube and pipe journal coverage describes, and it scales well to multipass caps where repeatability matters more than finesse.

When Freehand Is the Only Option

Some drawings and specifications simply prohibit scratching the base material, which rules out both wiggling and walking for those passes. Welders have to hover the torch, prop a finger on adjacent steel, and steer by feel. Freehand also solves access problems: Baker’s Gas warns that obstructions such as other pipes or walls can make cup walking impossible, so a welder who only knows one technique is already limited.

Why Pros Learn All Three

Real jobs mix conditions. The same welder might wiggle the root, walk the fill, and freehand a tie-in where a structural beam blocks the roll. Learning all three also protects your career path; if you’re considering formal training, an Aerospace TIG Welding program, for instance, expects fluency across techniques rather than a single trick. Start with whichever motion feels natural, then deliberately drill the other two until each one is automatic on the joint type it suits best.

Common Cup Walking Mistakes and How to Fix Them

Walking the cup looks effortless when a pro does it: the torch rocks along the bevel and the bead stacks into even ripples. When you try it, the cup skates off the joint and the arc hisses. Almost every beginner failure traces back to a short list of faults, matched below by symptom, cause and fix.

Death-Gripping the Torch

Squeezing the handle locks your wrist, and a locked wrist cannot roll, so the rock becomes a jerky ratchet with cup pressure swinging heavy then light. The bead shows it as uneven ripples. Hold the torch like a pencil, not a hammer, rest your ring finger on the pipe as a tripod, and take the pinky off the body so tension never reaches your forearm. this detailed breakdown of walking the cup mechanics covers grip and hand position.

Slipping Off the Joint

Symptom: the cup wanders off the bevel and the toe line snakes. Cause: a cup too small for the groove, a torch angle too steep, or pressure pushing forward instead of into the pipe. Fix: bump up one cup size, bring the torch closer to perpendicular in travel, and push the cup into the pipe wall. Forward motion should come from the rocking geometry, not shoving ahead, which gouges the bevel.

Too Much Tungsten Stick-Out

The rule of thumb: stick-out roughly equals the cup diameter. Extend much past that and the arc cone widens, gas coverage thins at the edges, and the arc wanders and licks the groove walls. The tell is an arc that floats and a bead that drifts sideways even when your hand feels steady. Trim the tungsten back and let the cup set the distance.

Wrong Cup Size for the Groove

A cup too large for a narrow root bottoms out on the bevel face or rocks with almost no travel per step, so you chatter in place. Too small on a cap gives choppy steps and thin gas coverage. Many welders start around a No. 6 for the root, No. 7 for fill and No. 8 for the cap, then adjust for wall thickness, gap and bevel angle.

Wandering Arc Length

Because the cup sets your electrode-to-work distance, arc length should stay nearly constant around the pipe. If it changes, the cup is not seated evenly or your pressure is pulsing. Listen: a steady hiss is right, and a crackle that shifts pitch means the arc is breathing, which is what spits tungsten. Resettle the cup flat and let the rock hold the gap.

Inconsistent Rhythm

Uneven ripples are a rhythm problem before they are a heat problem, usually from watching the puddle instead of counting steps or repositioning mid-pass. Pick a cadence you can repeat without thinking and save repositioning for a tie-in point. A steady cadence keeps heat input even from 6 o’clock to 12, more than raw travel speed does.

Cup Marks, Scratches, and Gouges

An alumina cup grinding along clean pipe leaves a witness line. That hardly matters on carbon steel skids, but on stainless tube, instrumentation work or aerospace TIG welding, where surface condition is specified, cup scratches can be flagged as surface defects. Prevention beats polishing: keep the cup face free of spatter and dust, replace chipped cups, and walk on the bevel or finished bead rather than virgin base metal.

Dipping the Filler Rod into the Tungsten

The arc goes wild and the puddle turns erratic. The cause is feed direction, not clumsiness: the rod enters the arc stream instead of the leading edge of the puddle. Keep the tip just ahead of the pool and dab in rhythm with your steps. After a dip, regrind on a dedicated tungsten wheel, never one used for steel or aluminum. Our all-position welding rod guide covers filler handling.

Burning Through the Root

Usually too much amperage for the gap, travel too slow, or stepping too tightly and parking. Drop 5 to 10 amps, quicken the cadence, and keep the puddle on the leading edge rather than lagging. Feathered, well-positioned tacks also keep the root from sinking when you tie in.

Undercut at the Toes

A groove melted into the base metal along the bead edge, caused by heat pooling mid-weave, travel too fast at high amperage, or a cup angle aimed at the joint center. Narrow the weave, ease the amperage, and let the puddle wash out to both toes before stepping forward.

Crater Pipes

TWI’s guidance on weld defects links crater pipes in TIG welding to arc shutdown and solidification shrinkage, and says they are prevented by reducing current progressively or adding filler as you finish. Without a foot pedal, dab extra rod while you taper your travel, take a short backstep before breaking the arc, and hold post-flow over the stop.

Porosity: When the Shielding Gas Is the Culprit

TWI reports that as little as 1 percent air entrainment in the shielding gas causes distributed porosity, while more than 1.5 percent produces gross, surface-breaking pores. Air enters through leaky fittings, a cracked collet body, or flow set so high it pulls air into the stream. Fix leaks with soap solution, run a flowmeter rather than a regulator, and remember gas lenses cover better at lower flow. Oily rod and dirty base metal cause porosity too. See our guide to welding gas supplies.

None of these fixes take talent. Diagnose honestly, change one variable, run another coupon.

Where Cup Walking Shines — and Where It Shouldn’t Be Used

Not every joint is a good candidate for walking the cup. While this technique can save hours of welding on the right setup, forcing it onto the wrong one will only make a clean weld harder to achieve. Knowing its sweet spot, as well as its hard limits, is just as important as learning the motion itself.

Where Cup Walking Shines

In most shops, cup walking is primarily used for pipe butt welds and socket welds, and is less practical on plate tee joints. Its ability to maintain a consistent arc length by riding the cup against the joint makes it ideal for any application where you need a uniform, multipass weld around a curve.

Some of the places where it excels the most include:

• Pipe butt welds: This is the bread and butter for cup walking. Whether it’s carbon steel or stainless steel, the constant pivot around the pipe allows for smooth travel without the twitchy wrist fatigue that comes with constant freehand wiggles.
• Socket welds and flange-to-pipe welds: The tight, consistent radius of a socket or flange face gives the cup plenty of contact to roll along, making tie-ins much easier to control.
• Tube fabrication: For medium to heavier wall tubing, cup walking provides repeatable results, especially when welding out of position and moving from the 6 o’clock position up to 12 o’clock.
• Multipass caps: Once the root and fill passes are in, the cap is where the “roll of the barrel” motion truly shines. With the right cup, you can lay down a smooth, convex cap with minimal weaving.

For full-penetration stainless steel pipe and tube, extra precautions need to be taken. According to The Fabricator, back purging (covering the weld root with shielding gas) is recommended for full-penetration welds to prevent oxidation and sugaring. Without it, the backside of your root can become heavily scaled, forcing unnecessary cleanup and compromising corrosion resistance.

With stainless, heat discoloration is also a reality. As a rule of thumb, stainless heat tint is easiest to remove with a wire brush about a minute after welding, while the metal is still warm. Waiting until it’s ice cold will make those stubborn oxides far harder to get off, whilst brushing far too aggressively can also risk marring the surface.

Where It Shouldn’t Be Used

As reliable as cup walking is, there are plenty of jobs where it’s the wrong tool for the job entirely. Trying to force contact can cause more harm than good, both to your weld and your cup.

• Thin-wall tube: On very thin wall material, the added pressure of riding the cup against the joint leaves little room for error. Even the slightest bit of drag can push heat into an already fragile wall and result in burn-through. For these jobs, a delicate freehand approach is usually much safer.
• Aluminum TIG: Aluminum TIG generally uses collet-body torch setups and different technique, making cup walking a poor fit. Unlike steel, aluminum’s thermal conductivity and puddle fluidity don’t lend themselves well to rolling a cup against the joint. For those looking to get consistent results on aluminum, learning processes such as those outlined in Aluminum MIG Welding: The Complete Practical Guide will be far more practical than trying to walk the cup.
• Restricted spaces: If your torch can’t physically rest its ceramic cup flush against the joint without binding on adjacent fittings, pipes, or structural members, don’t force it. Tight corners and awkward obstructions almost always call for a freehand or modified wiggle technique.
• Code work that forbids cup marks: Some codes and customer specifications explicitly forbid cup contact marks on the weld face. These marks aren’t necessarily defects, however they can be cosmetic reasons for rejection on visible, sanitary, or strictly inspected work. If the spec says no contact, freehand is your only option regardless of how pretty your cup walk may be.

At the end of the day, cup walking isn’t about walking every joint that you can. It’s about picking the curved, accessible joints where riding the cup gives you consistency, and abandoning it the moment the joint fights back against contact. Master that discernment, and you’ll know exactly when this technique is your greatest advantage, and when it’s better left in the toolbox.

Practice Drills: How to Build the Muscle Memory for Cup Walking

Knowing the theory behind cup walking is only half the battle. The real skill comes from training your muscle memory until the rocking motion becomes second nature. Much like learning to drive a stick shift, the key is to train slowly, with intention, and only increase speed once the fundamentals are locked in. With the right drills, even a complete beginner can go from an awkward, jerky cup roll to a fluid, consistent walk.

Starting With Dry Runs (Power Off)

Before striking an arc, you should be able to complete the motion flawlessly with zero power. This is the most important step for building coordination without worrying about puddle control.

A widely used drill from AWS forums is to score a line around a clean practice pipe with a cutoff wheel. This visible line acts as your target, allowing you to track your consistency while under the hood. For your setup, use a practice pipe between 3 and 4 inches in diameter, as these are much easier to learn on than smaller bore pipe.

For your torch, equip a No. 7 or No. 8 cup, set your tungsten stick-out to 1/4 to 5/16 inch, and aim for a tungsten-to-work distance of about 1/16 to 3/32 inch during your dry runs. With the power off, rest the cup onto the joint and practice walking the pipe around. Your goal is not to cover ground quickly, but to maintain a perfectly consistent rhythm from start to finish.

Low Amperage Arc Practice

Once your dry run is smooth with no hesitation or slipping, it’s time to strike an arc. Keep your amperage very low, between 40-50 A, as this will give you a small, manageable puddle that won’t punish small errors.

Focus only on motion at first. Do not add filler rod until your walk is consistent for a full rotation. Pay extra attention to the 3 o’clock to 12 o’clock and 9 o’clock to 12 o’clock passes, as these are the most common positions to lose control of travel speed. Remember the golden rule: your travel speed should be dictated by the puddle, not the other way around.

Feathering, Transitions, and Adding Filler

As you progress, you’ll need to refine your oscillation width, also known as feathering. A common mistake is making massive rocks from toe to toe. Instead, keep your oscillation tight at the start of your motion and subtly widen or tighten based off of the puddle size. This will drastically improve tie-ins between each rock, allowing you to achieve those clean, stacked dime looking beads.

Only when you can produce a clean, consistent stringer with no filler for at least a full quarter rotation should you introduce your rod. Add it at the leading edge of the puddle, only when the rock naturally brings the cup to the high side. This is much easier to master when compared to more finicky processes, such as the ones covered in our guides on aluminum MIG welding, where puddle behavior can be drastically different.

A Week-By-Week Practice Structure

Consistency trumps marathon sessions. Ten to fifteen focused minutes a day will be far more effective than a 5 hour, frustrated grind once a week. Follow this progressive structure to safely build your skill:

Remember, perfection is not the goal of these drills, consistency is. If your tenth rotation looks better than your first, you’re on the right track. Once your motion is locked in on mild steel, you’ll have an incredibly transferable foundation to utilize across more specialized processes. Keep your sessions short, your amperage low, and your focus on the rock. Before you know it, the cup will walk for you.

Safety, Fumes, and Ergonomics of Cup Walking

When walking the cup for precision pipe welds, your technique is only half the battle. The other half comes down to protecting yourself from the hidden hazards of GTAW. While TIG may look cleaner than other processes, it still carries serious risks if proper safety measures are not taken. This section will break down those risks, along with the ergonomics needed to keep you welding for years to come.

Shielding Gas Hazards and Confined Spaces

One of the most overlooked dangers while cup walking is your shielding gas. Argon is an inert gas, meaning it is non-toxic, but that doesn’t mean it’s safe in tight areas. According to OSHA, inert gases such as argon displace oxygen and can cause suffocation, especially in confined or enclosed spaces.

For welders working on large bore piping or vessels, never rely on your senses alone. Proper ventilation, air monitoring, and an entry permit system are crucial. This is especially important for those branching into specialized work such as Aluminum Boat Welding or Aerospace TIG Welding, where tight compartments are common.

Fumes, Ozone, and Nitrogen Oxides

Although TIG produces little visible fume compared to SMAW or FCAW, it is far from fume-free. The intense UV radiation from the arc reacts with the surrounding air to create ozone and nitrogen dioxide. These gases are highly irritating to the upper respiratory tract, causing coughing, chest tightness, and shortness of breath with prolonged exposure.

More importantly, the base metal itself can be hazardous. When welding stainless steel, the process generates hexavalent chromium, a known carcinogen. OSHA’s hexavalent chromium PEL is 5 micrograms per cubic meter of air as an 8-hour time-weighted average (29 CFR 1910.1026). Additionally, AWS Safety and Health Fact Sheet No. 4 states that welding fume is on the IARC list as posing a lung cancer risk to humans.

For this reason, local exhaust ventilation (LEV) should always be utilized over general dilution alone. If LEV is not feasible, a properly fitted respirator approved for welding fume and hexavalent chromium is required. These precautions are just as vital for high alloy work, including Alloy 20 Welding, as they are for everyday stainless pipe.

Personal Protective Equipment (PPE)

The precision of walking the cup means you’ll be in close proximity to the arc for extended periods of time. This increases your exposure to UV, infrared, and spatter. Be sure to utilize the following PPE:

• Eye and Face: Use a welding helmet with the correct shade selection for your amperage. For most TIG cup walking applications, a shade between #9 and #12 is recommended.
• Hands: Thin, flexible TIG gloves allow for the wrist control needed for the rolling motion, but still provide heat protection.
• Body: Wear flame-resistant leathers or welding jackets to protect against radiant heat and accidental contact with hot pipe.
• Respiratory: Utilize a compliant respirator when welding stainless or in poorly ventilated areas to adhere to the PEL requirements.

For those looking to further their career path through an Aluminium Welding Course, these PPE fundamentals will always be at the forefront of your training.

Ergonomics: Protecting Your Wrists and Body

The hallmark of a great cup walker is rhythm. However, the repetitive wrist motion and awkward posture required to weld pipe from 6 o’clock to 12 o’clock can lead to long term strain. Without proper ergonomics, tendonitis and back pain become very real issues.

To combat this, try to keep your torch hand relaxed, utilizing the cup as a natural pivot instead of death-gripping it. Position your body to weld in a comfortable stance, adjusting the pipe rotation whenever possible. Take micro breaks between passes to stretch your wrists and shoulders. These small habits not only prevent injury, but they drastically improve your consistency as well.

Whether you’re supplying your shop through AllGas Welding Supply, or perfecting your craft with premium setups from Airgas Welding Supplies, your most valuable tool will always be your health.

Creating a Safe Work Environment

Lastly, safety starts before you strike an arc. Ensure your shop has adequate shop ventilation with dedicated fume extraction at the source. Keep cylinders secured, properly labeled, and away from high traffic areas. For those managing their own workspace, resources such as Air Gas Welding Supply can help educate on safe cylinder handling.

By prioritizing these precautions, you’re not just passing inspection, but you’re also ensuring that you can continue to walk the cup for a lifetime of quality welds.

Quality, Codes, and Final Tips for Consistent Cup-Walked Welds

Walk up to a finished pipe weld and you can tell in a second whether the cup was walked with a steady hand: evenly spaced ripples, toes tied in smoothly, and a bead width that never wanders. That look is not vanity. Visual uniformity is the first and cheapest inspection, and a reliable signal that heat input, travel speed, and arc length held constant.

What a \”Good\” Cup-Walked Weld Looks Like

Quality on a cup-walked butt weld comes down to four things an inspector checks first:

• Uniform ripple spacing. Even ripples mean even rhythm and even heat input. Irregular spacing exposes a welder who sped up, repositioned awkwardly, or lost arc length.
• Clean tie-in at the toes. The bead should blend into the base metal without a sharp step or a cold edge. Toe undercut and a ropey, sitting-on-top bead mean too much travel speed or too little amperage.
• Correct root penetration and reinforcement. Too little and the joint is starved; too much and you have a proud root that obstructs flow and invites stress. On a full-penetration stainless weld the root must also be free of oxidation, which is why back purging matters on stainless tube and pipe.
• No surface-breaking defects. Porosity, cracks, inclusions, and lack of fusion are rejectable under most codes. Porosity can hide inside an otherwise attractive cap, which is why appearance alone never signs off a pressure weld.

How Pipe Welds Are Actually Inspected

Most code work runs in layers. Visual inspection (VT) comes first: profile, width, ripple consistency, undercut, spatter, and start-stop overlap. If it passes and the service demands it, nondestructive examination follows.

The uncomfortable truth for beginners: RT and UT reveal internal defects a good-looking cap can hide. The cap is the resume; the root is the job. On aerospace, pressure, and alloy work, welders follow a written procedure specification and qualified ranges rather than personal preference, as covered in aerospace TIG welding standards and training.

Rhythm Beats Speed Every Time

Consistent rhythm and arc length are why cup walking produces uniform welds at high production rates. New welders chase inches per minute; experienced ones chase a metronome. A steady beat keeps puddle width constant, constant arc length keeps heat constant, and speed is just the byproduct of rhythm plus rod feed.

Heat control matters more as the groove fills. A hot pass should move quickly across the center and dwell at the toes where it ties in, so it never sits long enough to remelt the root. As deposited metal narrows the groove, step up cup size so the cup does not bottom out. A No. 6 that walked the root beautifully will skip and chatter once the joint is half full; a No. 7 or No. 8 restores the contact geometry.

The 10-Point Cup Walking Checklist

1. Fit-up tight, tacks feathered, before striking an arc.
2. Cup sized to the pass: No. 6 root, No. 7 fill, No. 8 cap.
3. Stick-out about equal to cup diameter, tungsten ground sharp.
4. Cup pressure into the pipe, not pushing the torch forward.
5. Arc length set by the cup, not your wrist.
6. Steady, repeatable rhythm — beat first, speed later.
7. Hot pass brisk across the center to protect the root.
8. Cup stepped up as the groove fills, never bottoming out.
9. Puddle pulled to the high side on out-of-round pipe.
10. Amperage tamed via downslope, pulse, or careful scratch-start control.

Underneath all ten is one habit: consistency. The cup walking motion itself is simple to describe and simple to practice; the skill is repeating it identically around the whole circumference while your arms are tired and the pipe is hot.

Final Word

Back to the question this guide opened with: what is TIG welding cup walking? Resting the ceramic cup on the workpiece and rocking it so the torch pivots in a fixed, repeatable path — the cup sets your arc length while your wrist supplies a light, even oscillation. Done properly it gives uniform beads, consistent penetration, and the speed to keep up on production pipe, the signature skill of GTAW pipe welding. Learn it with dry runs, build it with rhythm, and let inspection come back clean. The same obsession with prep, procedure, and consistency carries into processes like Alloy 20 welding procedures and filler selection.

Frequently Asked Questions

What does walking the cup mean in TIG welding?

Walking the cup means resting the torch’s ceramic nozzle on the workpiece and rocking or rolling it along the joint so the nozzle acts as a guide. This keeps arc length and travel speed steady, producing uniform, repeatable beads without propping your hands on hot metal.

What cup size should I use for walking the cup?

A No. 6 cup works well for root passes, a No. 7 for fill passes, and a No. 8 for cap passes on typical pipe. Larger cups give a wider motion and better gas coverage but may not fit into a narrow groove, so match the cup to the joint geometry.

How far should the tungsten stick out when walking the cup?

A common rule of thumb is to keep tungsten stick-out roughly equal to the cup’s diameter, though many welders extend it slightly further for better visibility. The key is that the arc reaches the joint root while the cup stays in contact with the work.

Is walking the cup harder than freehand TIG?

It is different rather than harder. Freehand demands steady hands and constant amperage control, while cup walking demands rhythm and correct pressure direction. Most welders find the cup-supported motion easier to keep consistent once the basic rocking movement clicks.

Can I walk the cup on plate and fillet welds?

Yes, especially on a tee joint where the cup can sit in the corner, but it is far more practical and common on pipe and tube. On flat plate the cup has nothing to guide it, so a freehand or wiggling technique is usually a better fit.

Why does my cup-welded bead look great but leak or fail inspection?

A good-looking cap can hide internal defects such as lack of fusion, porosity, or a burned-through root. Tight fit-up, correct amperage, proper gas shielding, and where required back purging of stainless roots are what keep the inside of the weld sound.

Does cup walking leave scratches that count as defects?

On some jobs, especially stainless or where surface finish is specified, cup scratches are rejected and welders must freehand instead. Check the welding procedure specification before starting, and grind out or remove any marks the code does not allow.

How do I stop the cup from slipping while learning?

Push the cup perpendicular to the pipe axis rather than in the direction of travel, keep light pressure, and practice on a scored line with the power off before striking an arc. Starting on 3- to 4-inch pipe at low amperage makes the motion much easier to control.

Do I need a foot pedal to walk the cup?

No. One of the technique’s advantages is that it works with simple setups — many field welders walk the cup using lift-arc TIG on a basic power supply with no remote control, adjusting amperage between passes instead of during the weld.