Overview

Brass mesh etching uses photochemical machining to cut precise apertures and strand patterns into thin copper-zinc sheet without mechanical force or a stamping die. A photoresist mask is imaged with the mesh artwork, developed, and the unprotected brass is dissolved in a ferric-chloride or cupric-chloride chemistry, so hole shape, hole size and strand width are fixed by the artwork and etch time rather than by tool pressure. Typical substrates are C26000 cartridge brass, C26800 yellow brass and C27200, supplied between 0.05 mm and 0.6 mm. Because the process is chemical, the mesh leaves the line flat, burr-free and free of the rolled edges, tool wear and work hardening that come with punching thin brass, while the alloy keeps its warm metallic appearance and useful electrical conductivity.

For buyers of EMI shielding screens, decorative grilles, acoustic meshes and precision sieves, the process solves three recurring problems. Brass is soft and ductile, so stamping thin foil tends to burr, curl and smear fine holes; RF and acoustic parts demand uniform apertures and high open area that are hard to hold below 0.3 mm; and bare brass tarnishes and can dezincify in humid or acidic service. Chemical machining forms every aperture on a sheet at the same rate, holding hole size and strand width consistent from the first sample through volume production, and a benzotriazole anti-tarnish or plated finish locks in surface stability before the part reaches assembly.

Parameter Window

• Available Materials: C26000 cartridge brass (70/30), C26800 yellow brass, C27200; also phosphor bronze and copper for mixed builds
• Material Thickness Range: 0.05–0.6 mm
• Tolerance: ±0.02 mm on aperture size, ±0.03 mm on strand width, open area within ±2%
• Minimum Feature: 0.10 mm hole diameter, 0.08 mm strand width, open area up to ~65%
• Surface Options: benzotriazole anti-tarnish, bright dip & passivation, nickel/tin/gold plating, clear lacquer, ultrasonic cleaning
• Compliance: ISO 9001 process control, RoHS/REACH material traceability

Manufacturing Process / Workflow (8 Steps)

1. Artwork & Nesting — Convert the hole array to vector art, check the hole-to-thickness ratio, and plan sheet layout with shared registration marks.
2. Material Certification & Prep — Verify alloy, zinc content, temper and thickness, then shear to exposure size and inspect flatness.
3. Cleaning & Lamination — Degrease and laminate dry-film resist under matched heat and pressure so no bubbles sit under fine strands.
4. UV Exposure — Expose through high-resolution film with the array registered to the sheet edge for panel-level aperture consistency.
5. Development — Wash out unexposed resist to open the hole areas and inspect for residue that would block etching.
6. Controlled Etching — Spray brass-matched chemistry, tuning time, temperature and conveyor speed to avoid dezincification and strand thinning.
7. Stripping & Anti-Tarnish — Remove resist, neutralize, then apply anti-tarnish, plating or lacquer to stabilize the reactive brass surface.
8. Inspection & Packaging — Measure aperture, strand width and open area on a vision system, verify flatness, then interleave and pack in clean trays.

Core Advantages

1. Burr-free open area: Chemical removal leaves no rolled edge or burr, so flow and sound transmission stay stable and no particles shed downstream.
2. No die cost: Each new mesh pattern is a new film, keeping prototypes and frequent decorative revisions economical without a stamping tool.
3. Conductive shielding: Brass conducts well, so a fine etched screen doubles as an EMI/RF shield while still passing air or sound.
4. Repeatable fine holes: 0.10 mm holes and 0.08 mm strands form together across a sheet, with tight aperture spread and uniform open area.
5. Stress-free flatness: With no shear or heat input, thin foil stays flat, so bonding, laminating or framing will not warp the mesh.
6. Decorative finish ready: Brass mesh etching accepts nickel, tin, gold or clear lacquer, giving a durable warm finish for visible grilles and panels.

Typical Applications

• EMI/RF shielding screens: Conductive vent and window meshes that block interference while allowing airflow in enclosures.
• Decorative & architectural grilles: Patterned brass screens for speaker covers, vents, luminaires and interior panels.
• Speaker & acoustic meshes: Thin grilles with high open area that protect drivers without muffling high frequencies.
• Precision sieves & filters: Laboratory and industrial screens with narrow aperture distribution for repeatable particle separation.
• Heat-exchanger & fuel-cell screens: Perforated support meshes where conductivity and corrosion behavior matter.
• Instrument dials & inlays: Fine brass grids and calibration patterns for gauges, badges and decorative trim.

Design Notes & Process Considerations

1. Hole-to-thickness ratio: Keep hole diameter at or above material thickness; too small a hole distorts from undercut and thins the strand.
2. Open-area callout: State hole diameter, pitch and open-area percentage, and define round, square or hex arrays rather than only a mesh count.
3. Alloy selection: Choose C26000 for formability, C26800 for color and cost, and note zinc content where dezincification resistance is specified.
4. Tie bars and borders: Leave enough process border and tie bars, and specify the final cut method so thin webs survive stripping and plating.
5. Tarnish control: Bare brass oxidizes quickly; call out anti-tarnish, plating or lacquer and the allowable color shift after assembly.
6. Surface and cleanliness: With brass mesh etching, define plating thickness, residual-ion limits and handling, especially for RF and acoustic parts.