Welding Wire Mesh and Filtration Components: What Machine Do You Need?
What Makes Mesh and Filtration Welding Different from Battery Welding
Most people who come to resistance welding through battery tab welding — spot welding nickel strip to 18650 cells — encounter capacitive discharge welding first. CD is the right technology for that application. But the same people who then need to weld wire mesh, filter screens, or hermetic seals discover quickly that their CD welder doesn't solve the problem.
The reason comes down to what the application actually requires. Battery tab welding needs a discrete spot — a localised fusion at one point, in one millisecond, without disturbing the surrounding material. Wire mesh welding needs something fundamentally different.
For the background on how CD welding works and why it's the standard for battery tabs, our what is a CD spot welder guide covers the mechanism.
Watch this overview of AC resistance welding for wire mesh and filtration applications:
Fine Wire Diameters
Wire mesh for filtration is typically made from fine stainless steel, Monel, or nickel alloy wire in diameters from 0.05mm to 0.5mm. At these wire diameters, the mass of material at each weld point is tiny. A CD pulse calibrated for 0.15mm nickel strip (a flat tab spanning a 18mm cell terminal) carries far more energy than needed to fuse two crossing 0.1mm wires. The excess energy burns the wire rather than fusing it.
Fine wire mesh welding requires the ability to control weld energy down to levels where fine wire diameters are fused cleanly, not melted through. Sunstone AC resistance spot welders can be adjusted down to weld times as low as 1/100 second, and typical welding applications range from sheets as thin as 0.05mm — the energy resolution required for fine mesh work.
Seam Welding vs Spot Welding
A filter basket seam, a hermetic seal around a pouch cell, or the perimeter join where mesh is attached to a strainer frame — these are all continuous joints. They require every point along the seam to be fused with consistent energy in a continuous pass.
CD welding creates discrete spots. You can create overlapping spot welds that approximate a seam, but a true seam weld — where the electrode continuously traverses the joint with sustained current — requires AC resistance welding. The AC transformer draws continuous current from the mains through the electrode for as long as the trigger is held. Combined with a roller electrode, this creates a genuine continuous fused seam rather than a row of discrete spots.
Hermetic Seal Requirements
Filter assemblies, battery pouch cells, and medical device housings often require hermetic seals — seams where no leak path exists along the joint. A hermetic seal requires continuous, unbroken fusion along the full seam length.
Spot weld rows, even densely overlapping ones, have unwelded metal between each spot. Under pressure or vacuum, this creates a potential leak path. A continuous AC seam weld — current flowing throughout the electrode traversal — produces a genuinely hermetic joint when correctly executed.
Common Mesh and Filtration Welding Applications
Filter Baskets and Strainer Bodies
Cylindrical filter baskets (used in hydraulic systems, chemical processing, water treatment, and HVAC) are assembled by welding wire mesh panels to cylindrical frames or by welding the seam on a formed mesh cylinder. Both the attachment seam (mesh-to-frame) and any longitudinal seam require continuous seam welding for structural integrity and leak performance.
AC resistance seam welders create and build filter assemblies, filter bodies, and attaching mesh screen to a strainer basket. Additional applications include filter baskets and any metal filter or screen.
Wire Screen and Mesh Panels
Flat wire mesh panels — for air filtration, liquid straining, security screens, or industrial grating — are produced by welding every wire intersection across the panel. In production, this is done with roller electrodes in seam mode: the electrode rolls across the panel welding each intersection as it passes.
A CD welder making individual spot welds at each intersection would take dramatically longer for the same panel and would produce less consistent intersection welds than a continuous AC seam pass. For panel production at any meaningful volume, AC seam welding is the only practical technology.
Pouch Cell and Foil Sealing
Lithium pouch cells use a foil-laminate casing sealed along the perimeter edges. The seal is a hermetic seam weld around the cell perimeter — distinct from the tab welding inside the cell (which uses CD). The seam sealing of the pouch casing is an AC resistance seam welding application.
Similarly, any application involving very thin metal foil (0.05–0.1mm) benefits from AC's controlled sustained current over CD's high-peak pulse, which tends to penetrate foil too aggressively.
Medical and Pharmaceutical Filtration
Medical filtration components (surgical suction filters, IV line filters, blood processing components, implantable device housings) require hermetic welds with full traceability and consistent energy delivery documented for each production lot.
The Sunstone Wave AC's digital energy control and weld parameter storage (100+ weld schedule storage) provides the process documentation capability needed for medical device manufacturing environments. The waveform visualisation also allows engineering teams to verify parameter delivery without destructive testing on every component.
Food-Grade Filtration
Food-grade stainless steel filters (for beverage, dairy, and food processing) use 304 or 316L stainless steel wire mesh welded into strainer baskets, filter cones, and inline filter housings. The weld itself must be smooth and free of crevices (where product and bacteria can accumulate) — which a continuous seam weld achieves more reliably than a row of spot welds.
Water cooling is often used for extended seam welding runs on larger food-grade filter assemblies, as sustained seam welding at high duty cycles generates heat that benefits from active cooling of the weld head cables and electrodes.
Why CD Welding Is Not Ideal for Mesh Work
The Fast-Pulse Problem on Thin Materials
A CD pulse for battery tab welding is calibrated for 0.1–0.3mm nickel strip — a relatively massive target compared to fine mesh wire. The peak current in a CD pulse is very high (thousands of amps in milliseconds), which is what makes it effective for overcoming copper's high thermal conductivity during tab welding.
Applied to a 0.1mm wire intersection, this peak current is orders of magnitude above what the wire mass can absorb before burn-through. Even at minimum joule settings, the energy-to-wire-mass ratio for fine mesh is unfavourable. CD welders' joule ranges are calibrated for tab welding applications; fine wire mesh typically requires energy levels below the practical minimum of most CD systems.
Heat Distribution on Seam Welds
CD's fundamental mechanism — charge, position, trigger, single pulse — cannot produce a continuous seam. Each trigger press creates one spot. To weld a 50mm seam, you need multiple trigger presses and precise electrode repositioning between each, producing a row of discrete spots rather than a continuous seam.
For the complete explanation of why these two technologies serve different applications and cannot substitute for each other, our AC vs CD welding guide covers the comparison across all application types.
Why AC Resistance Welding Is the Right Technology
Controlled Heat Input Across a Seam
AC resistance welding draws current continuously from the transformer throughout the weld event. The operator (or automated system) controls weld duration in fractions of a line cycle (down to 1/100 second). This continuous energy delivery can be modulated to exactly the level needed for each wire diameter — enough to fuse the intersection, not enough to burn through.
For stainless steel wire mesh: stainless has relatively high electrical resistivity (approximately 70–100 nΩ·m depending on alloy), which means it generates heat efficiently under resistance welding current without requiring the very high peak currents needed for copper. AC resistance welding current levels are well-matched to stainless mesh heating requirements.
Roll Spot and Continuous Seam Capability
The AC resistance welder's seam mode, combined with a roller electrode (the EL-Roll or equivalent), creates a continuous current path as the electrode rolls along the seam. Every point along the electrode's travel path receives current — there are no skipped areas between discrete spots.
The wave AC's seam mode, combined with wheel electrode compatibility, enables continuous welding operations essential for manufacturing processes, allowing operators to create consistent, uninterrupted welds along extended material lengths, making it ideal for filter assembly and mesh welding.
Roll-spot mode (a hybrid) creates a series of closely overlapping spot welds in rapid succession, producing a near-seam without the full continuous seam mode. This is useful where the seam geometry requires more precise individual spot placement than a continuous roller pass.
Consistency on Fine Wire
Fine wire mesh welding at intersections requires that every wire junction receives essentially the same energy. Variation from intersection to intersection produces a mesh with weak points at under-welded junctions that fail under mechanical load or pressure.
AC's continuous transformer-based current delivery, combined with digital parameter control, produces consistent energy at each intersection in a seam pass. The Sunstone Wave AC uses digital energy control via a 10-inch colour touchscreen with real-time waveform visualisation — as operators make changes, they can see exactly how these adjustments impact the welding process. This feedback allows precise tuning for specific wire diameters without destructive testing of every production lot.
The Sunstone Wave AC + PG2 System
What the Wave AC Does
The Sunstone Wave AC is Sunstone's professional AC resistance welding system, delivering up to 2,700 amperes through a digitally controlled transformer. Key specifications and features:
- Output: Up to 2,700 amperes
- Control interface: 10-inch colour touchscreen with real-time waveform visualisation of all welding parameters
- Weld modes: Spot, roll-spot, and continuous seam
- Functions: Dual pulse, multi-pulse, foil welding, pouch cell welding, mesh/screen welding, continuous seam welding, temper functions
- Schedule storage: 100+ weld configurations; job chaining allows up to 10 jobs (schedules chained together for complex multi-step welding sequences)
- Electrode compatibility: Operates with standard pointed electrodes for spot work and roller electrodes (EL-Roll) for seam work
The Wave AC is an outstanding welding solution for continuous seam welds, foil welding, pouch cell welding, mesh or screen welding, hermetic sealing, and filter production applications.
What the PG2 Power Supply Adds
The PG2 is Sunstone's handheld welding pen designed specifically for seam and roll-spot welding with the Wave AC. It's commonly paired with the EL-Roll roller electrode for seam welding — the PG2 provides the mechanical structure for the operator to guide the electrode along the seam at consistent pressure and travel speed.
Key features of the PG2 configuration:
- Designed for manual seam traversal — the operator controls the travel speed and pressure as they guide the roller electrode along the joint
- Water cooling integration available (PG3W variant) for extended seam welding sessions at high duty cycles
- Enables roll-spot and seam modes that aren't accessible with a standard stationary handpiece
How the Bundle (Bundle 3) Works Together
Sunstone packages the Wave AC with the PG2 handpiece and EL-Roll electrode as a coordinated system (referred to as Bundle 3 in Sunstone's configuration options). This bundle provides:
- Wave AC power supply — digital energy control, 2,700A output, waveform visualisation, mode selection
- PG2 handpiece — operator interface for seam traversal with consistent electrode force
- EL-Roll roller electrode — the rolling contact electrode that creates the continuous seam current path
- Pointed electrodes — for spot welding work with the same system
This configuration handles the full range of mesh and filtration welding work: spot welding individual intersections for prototyping or small mesh pieces; roll-spot for controlled near-seam work; continuous seam for filter basket seams, hermetic seals, and mesh panel production.
What Else Do You Need for a Mesh Welding Setup?
Weld Heads and Electrode Selection
Electrode selection for wire mesh: The electrode tip geometry must match the wire diameter being welded. For very fine wire (0.05–0.1mm), a pointed or very small-radius tip concentrates current at the intersection. For larger wire (0.3–0.5mm), a flat tip distributes energy more evenly across the larger contact area.
Electrode material: Copper alloy (RWMA Class 2) is the standard for most stainless steel mesh welding — high conductivity to extract heat from the electrode quickly. Tungsten tips are used for applications requiring extended electrode life or where electrode erosion is a concern.
Roller electrodes (EL-Roll): Matched to the wire pitch spacing of your mesh. The roller diameter and width affect current distribution along the seam. Sunstone offers multiple roller configurations for different mesh geometries.
Fixturing and Part Positioning
Wire mesh welding quality depends heavily on consistent electrode-to-workpiece contact. Any variation in gap, tilt, or pressure between the electrode and the mesh intersection produces weld quality variation.
For production mesh welding: dedicated fixturing holds the mesh flat and at consistent height relative to the electrode. A flat, rigid backing surface ensures the mesh wires are fully in contact at each intersection before current flows.
For filter basket seam welding: rotation fixtures that allow the basket to rotate under a stationary seam electrode ensure consistent travel speed and electrode angle throughout the circumferential seam.
Water-cooling: for extended seam welding sessions (baskets with long seam lengths, large mesh panels), the PG3W water-cooled handpiece and recirculating water chiller maintain electrode and cable temperature in the acceptable range. Heat that builds in the cables without cooling degrades the cable insulation and affects current delivery consistency.
How to Specify the Right System for Your Application
Wire Diameter and Material
Wire diameter and material determine the energy level required and the minimum weld time needed to achieve fusion without burn-through.
- Very fine mesh (0.05–0.1mm wire): Minimum energy levels, shortest weld times, most sensitive to energy over-delivery. Requires a system with fine low-end energy control.
- Standard filtration mesh (0.1–0.3mm wire): Mid-range energy settings on the Wave AC.
- Heavier mesh and screen (0.3–0.5mm wire): Higher energy, longer weld time, more tolerant of energy variation.
Material matters too: stainless steel 316L (used in most filtration applications) is more resistive than 304 and requires slightly lower current for the same heat generation. Monel and Inconel alloys have higher resistivity still and may require parameter adjustment compared to standard stainless.
Weld Pitch and Seam Length
Weld pitch (spacing between individual weld spots, or distance per roll-spot cycle in seam mode) determines the density of intersection welds along a seam. For structural mesh (where every intersection carries load), tight pitch is required. For filtration mesh where flow path matters (you don't want to collapse the mesh structure by over-welding), appropriate pitch that fuses intersections without distorting the mesh aperture is the engineering parameter.
Seam length affects the requirement for water cooling. Seams under 100mm can typically be completed without active cooling in normal production volumes. Seams over 200mm at high duty cycles benefit from the PG3W water-cooled configuration.
Production Volume
Prototyping and small-batch (under 50 pieces per week): The Sunstone Wave AC with PG2 handpiece and manual seam traversal is appropriate. The operator controls seam speed manually.
Medium production (50–500 pieces per week): The Wave AC with more consistent fixturing and possibly semi-automated electrode traversal. Water cooling if seam length and duty cycle require it. The Wave AC's 100+ schedule storage allows rapid changeover between part programmes.
High-volume production: Discuss with Sunstone directly — their semi-automated manufacturing configurations are available for the Wave AC, and the digital control system integrates with automation control systems. The Wave AC is designed for semi-automated manufacturing environments that rely upon an AC welder.
For pricing guidance on the Wave AC system and how it compares to CD system investment, our how much does a spot welder cost guide covers the cost framework across resistance welding technologies. For the full detailed review of the Wave AC, see our Sunstone Wave AC review.
Frequently Asked Questions
What machine do I need to weld wire mesh?
Wire mesh welding requires an AC resistance welder, not a capacitive discharge (CD) welder. AC resistance welding provides continuous current through a transformer, which can be controlled for the fine energy levels needed to fuse fine wire intersections without burn-through, and can operate in continuous seam mode with roller electrodes for production mesh panel welding. CD welders create discrete millisecond pulses designed for spot applications like battery tabs — they cannot create true continuous seam welds and the pulse energy is not well-matched to fine wire diameters. For small-to-medium mesh welding production, the Sunstone Wave AC is the professional standard.
Can you spot weld wire mesh?
Yes, individual wire mesh intersections can be spot welded using AC resistance welding in spot mode — a stationary electrode contacts the wire crossing and fires a timed energy burst. However, for production mesh panel welding where every intersection across a panel must be fused, continuous seam mode with roller electrodes is far more efficient. The roller electrode traverses the mesh, fusing each crossing wire intersection as it passes, in a single seam pass rather than hundreds of individual trigger presses.
What is the best welder for filtration components?
The Sunstone Wave AC is the professional standard for filtration component welding in the US precision manufacturing market. It delivers up to 2,700 amperes with digital energy control, stores 100+ weld schedules for rapid changeover between part types, and operates in spot, roll-spot, and continuous seam modes. The Wave AC + PG2 + EL-Roll roller electrode bundle (Bundle 3) provides the complete system for filter basket seam welding, mesh-to-frame attachment, and hermetic seal applications.
Why can't I use a CD welder for mesh welding?
Two fundamental reasons: the CD pulse is too short and too high-peak for fine wire, and CD welding cannot produce true continuous seam welds. Fine wire mesh (0.05–0.3mm wire diameter) requires very low energy levels — below the practical minimum joule setting of most CD systems — delivered in controlled weld times. CD welding's millisecond high-peak pulse burns through fine wire rather than fusing it. Additionally, CD welders create one spot per trigger press; continuous seam welding requires sustained current as the electrode travels along the joint, which only AC transformer-based welding can provide.
What materials can be welded for filtration mesh?
The most common filtration mesh materials for AC resistance welding: stainless steel 304 and 316L (by far the most common — good corrosion resistance, predictable welding behaviour, widely used in chemical, food, and pharmaceutical filtration), Monel 400 (for marine and highly corrosive environments), Inconel alloys (for high-temperature applications), and nickel alloy wire. Galvanised steel mesh can be welded but generates zinc fume during welding (requires good ventilation). The Sunstone Wave AC is rated for these material types across wire diameters from 0.05mm to 1.2mm depending on material and orientation.
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