You landed a data center contract for 800 server rack assemblies. Your lead welder dialed in the program. First 50 units look great. Then you notice units 200-240 have slightly inconsistent bead placement because the fit-up varies just enough that the fixed torch path isn't ideal anymore.

Or you're programming a multipass weld on structural frames. You calculate the offsets for passes 2-6, run the program, and discover pass 4 doesn't land where you thought it would. Now you're reprogramming the entire sequence and burning material to test it again.

Or you've got a job that requires certified multipass welds on heavy material. You know what parameters you want for each pass. You know where each pass should go. But you're spending an hour calculating offsets and creating separate programs for each pass, and you won't know if it all works together until you run the complete sequence.

These aren't hypothetical problems. This is what stops fabrication shops from scaling data center work even after they've solved the capacity problem with collaborative welding systems.

The quality problem that emerges at scale

When you're welding 20 units, your best welder can make manual adjustments as needed. Quality stays consistent because one person is watching everything.

When you're welding 800 units across two shifts with production running overnight, those manual adjustments don't scale. You either accept more variation, or you need technology that can adapt to real-world conditions without requiring constant human intervention.

Data center projects require certified welders and dedicated certified welding inspectors to meet quality expectations that exceed industry standards. That certification requirement doesn't go away just because you're running higher volume. If anything, it becomes more critical—because when unit 500 fails inspection, you're explaining to a contractor why your process broke down.

Two technologies that address different problems

Through Arc Seam Tracking (TAST) solves the problem of variation during the weld—when your programmed torch path doesn't perfectly match the actual joint because fit-up varies, material isn't perfectly consistent, or fixtures have tolerance stack-up.

Multipass Welding solves the problem of programming and verifying complex multi-layer welds—when you need to build up thick joints with multiple passes and you want to verify each pass works before committing to the full sequence.

Both address the same fundamental challenge: maintaining quality when you scale production beyond what one experienced welder can manually oversee.

What Seam Tracking actually does (and doesn't do)

Through Arc Seam Tracking uses real-time electrical feedback from the welding arc to detect when the torch has drifted from optimal position and automatically correct it.

How it works: As the torch weaves across the joint, the system samples current at the left and right peaks of the weave pattern. Current differences between left and right indicate lateral drift—the system adjusts to re-center. Voltage samples at center positions detect height variations—the system corrects to maintain proper arc length.

Through-arc seam tracking uses feedback current to make adjustments to the robot's motion and adjust the weld path as needed when variations in the weld seam or gaps are detected, just like a manual welder would take that torch and move it over a fraction of an inch to reposition that weld bead.

What this solves: You're not stopping production to make manual torch adjustments when you notice the gap has opened up slightly or the material height has changed. The system handles minor corrections in real time while you maintain your production schedule.

What you still control: All welding parameters—current, voltage, travel speed, wire feed. Whether tracking is active and how sensitive it should be. Which parts of the joint to track. Every welding decision remains yours.

What it costs: $100 per month per robot that uses seam tracking. No hardware changes, integrates with your existing weave patterns, can be enabled or disabled as needed.

When you actually don't need Seam Tracking:

We've said before that welding cobots don't require seam tracking if you have good fixture design and repeatable upstream processes. That's still true for most shops most of the time.

If you can control your upstream production:

• Consistent material preparation
• Reliable fixturing
• Parts arriving with predictable fit-up
• Production volume that allows manual oversight

Then you probably don't need seam tracking. Adding complexity to compensate for inconsistency that you can eliminate at the source doesn't make sense. Fix the fixturing, improve material prep, and use simple repeatable programs.

But here's what changes at scale:

When you go from 50 units to 500 units, variables multiply. You can't control every upstream factor anymore:

• Material comes from different supplier lots with slight variations
• Second shift uses different fixturing techniques than first shift
• You're taking on work from multiple contractors with different tolerances
• Production volume means you can't have a welder inspecting every joint before welding

That's when seam tracking shifts from "unnecessary complexity" to "the only way to maintain consistency without dedicating a welder to constant oversight."

The decision framework:

• Can you eliminate the variation at the source? → Do that instead of adding seam tracking
• Is the variation inherent to your production scale or customer requirements? → That's when seam tracking makes sense

We're not saying you need this technology. We're saying if you're hitting quality inconsistency problems as you scale volume, here's how to solve them without scaling your labor.

The Multipass programming problem nobody talks about

Here's the workflow most robotic multipass programming requires:

• Teach your root pass
• Manually calculate offsets for each subsequent pass (how far left/right, up/down, forward/back each pass should be)
• Create programs for each pass with those calculated offsets
• Hope your math was correct
• Run the complete sequence on test material
• Discover pass 4 doesn't land where you expected
• Recalculate offsets, reprogram, test again

The problem isn't that this approach doesn't work—it's that every iteration wastes time and material, and you can't verify anything until you've programmed the entire sequence.

How Beacon Multipass Actually Works

Beacon eliminates the calculate-and-hope approach through verification at each step.

• Teach your root pass using standard welding techniques
• Convert to multipass in a few clicks—specify how many additional passes you need
• Use Guided Teach to position each pass: Move the robot to where you want the next pass to go. Beacon calculates the offsets automatically based on where you showed it
• Execute Pass to verify: Test just that individual pass. See if it works. Only continue after you've confirmed it's correct
• Repeat for each subsequent pass—building and verifying one pass at a time
• Add post-actions for heat management if needed—cooling delays, operator inspection pauses, or repositioning moves between passes

The competitive differentiator: You can edit any pass, at any time, without recalculating the entire sequence. Pass 4 needs adjustment? Edit pass 4. The rest of your sequence stays intact.

Other systems require you to do the math for each pass upfront and hope for the best. Beacon lets you build and verify incrementally, testing each decision before moving to the next and even changing a pass in the middle of your sequence.

What this costs: $100 per month per robot that uses Multipass feature.

Why this matters for shop owners

The cost of these features isn't the $100/month subscription. It's what happens without them when you're trying to scale production.

Without seam tracking:

• Production stops for manual torch adjustments when fit-up varies
• Quality becomes inconsistent across production volume
• You're either accepting more variation or dedicating a welder to watch every unit

Without multipass verification:

• Hours spent calculating and programming sequences that might not work
• Material wasted testing programs before you know if they're correct
• Entire sequences need reprogramming when one pass is wrong
• Can't confidently quote multipass work because programming time is unpredictable

With both capabilities:

• Real-time adaptation to variation without stopping production
• Build and verify multipass sequences incrementally—test as you go
• Edit and adjust without starting over
• Predictable programming time even on complex multipass work

For data center fabrication where an estimated 10 gigawatts of capacity is projected to break ground globally in 2025 alone, the fabricators winning contracts are the ones who can maintain certified quality across production volume. These technologies aren't about adding features—they're about making quality scalable.

The ROI equation

Here's the math that matters:

Programming time on multipass work:

• Traditional approach: 1-2 hours per new multipass sequence, with material waste during testing
• Beacon approach: 15-30 minutes with Execute Pass verification, minimal waste because you're testing incrementally

Production consistency with variable fit-up:

• Manual adjustment approach: Production stops, welder makes adjustments, quality varies by operator
• Seam tracking approach: Real-time correction, production continues, quality stays consistent

Cost to add capabilities:

• Traditional systems: Often baked into six-figure upfront costs or require expensive add-on hardware
• Beacon: $100/month per robot for each capability, cancel anytime, no hardware changes

If you're running one cobot on data center work and these capabilities save you 3 hours per week between faster programming and fewer production interruptions, you're at $75-100/hour value on a $200/month investment.

If you're running three cobots and these capabilities let you confidently quote multipass work you're currently turning down, the ROI isn't measured in saved hours—it's measured in contracts you can now win.

When you actually need these capabilities

You need seam tracking when:

• Your assemblies have fit-up variation that's within acceptable tolerance but enough to affect fixed torch paths
• You're scaling volume beyond what manual adjustments can handle
• Quality consistency matters more than speed (you're willing to invest in adaptive technology for better results)

You need multipass when:

• You're welding thick material that requires multiple passes for full penetration
• You need to build up strength on structural connections
• Contractors are specifying multipass procedures and you want predictable programming time

You don't need either when:

• Your parts have perfect consistency and fixed paths work fine
• You're doing simple single-pass work
• Volume is low enough that manual oversight handles all quality control

The question isn't "are these features cool?"—it's "does the work I'm trying to win require adaptive capability and verified multipass programming?"

For data center fabrication, the answer is increasingly yes.

Implementation reality

Both capabilities work with your existing Beacon setup through software updates. No new hardware. No reconfiguring your cell. No sending equipment back for upgrades.

Seam tracking integrates with your current weave patterns. You're not re-teaching paths or changing your welding approach. Enable it, set sensitivity for your application, monitor feedback, adjust as needed.

Multipass builds on your existing welding knowledge. You're still making all the decisions about parameters, positioning, and cooling strategies. Beacon just gives you tools to implement those decisions faster with verification at each step.

Both can be enabled or disabled per job—you're not locked into using them everywhere just because you have access to them.

The bottom line

Data center contractors aren't asking "can you weld?"—they're asking "can you maintain certified quality across 800 units when fit-up varies and half the work is multipass?"

Shops without adaptive capability are either accepting more variation (and higher rejection rates), dedicating welders to constant oversight (limiting volume), or turning down work that requires guaranteed consistency at scale.

Shops with Seam Tracking and Multipass can confidently quote that work because they've solved the quality-at-scale problem.

The competitive advantage isn't the technology itself—it's being able to say yes when contractors ask if you can handle their volume requirements without compromising on quality standards.

These capabilities are what separates fabricators who can scale data center work from fabricators who stay stuck at current volume because their quality processes don't scale.

Ready to See How These Work?

Beacon's approach to seam tracking and multipass makes advanced adaptive welding accessible without requiring robotics expertise or hardware changes.

Contact our team to explore how Beacon's adaptive welding features help shops maintain quality when they scale production.

Stop turning down work because you can't guarantee consistency at volume.