Brass Laser Cutting
Fiber laser cutting of CuZn37 and CuZn39Pb3 sheet from 0.5 to 6 mm for signage, decorative screens, electrical and plumbing parts
Brass laser cutting is done on fiber lasers of 3 kW and above, which cut CuZn37 (CW508L, 2.0321) and leaded CuZn39Pb3 (CW614N) sheet from 0.5 to about 6 mm with nitrogen assist gas. Brass reflects infrared light and conducts heat well, which made it difficult for CO2 lasers, but modern fiber sources with back-reflection protection cut it routinely. Tolerance is ±0.1 mm on sheet up to 3 mm, edges are bright and nearly dross-free with nitrogen, and the cut face shows a slight yellow-brown tint that polishes off.
Demand in Egypt, the UAE and Saudi Arabia is mainly decorative: mashrabiya-style screens, signage letters, hotel and mosque fittings, plus electrical busbar tabs and plumbing plates. Upload a DXF and receive a binding quote from CutLinq within 12 hours.
Brass grades and sheet availability
CuZn37 (CW508L, often sold as 'yellow brass' or 'cartridge brass 70/30 equivalent') is the standard sheet alloy: it cuts cleanly, bends to 1t and polishes to a warm gold. CuZn39Pb3 (CW614N) contains 3% lead for free machining; it is stocked as plate and bar for turned parts and cuts with a slightly rougher edge. CuZn30 (CW505L) is chosen for deep drawing and spinning. Architectural brass and 'naval brass' CuZn39Sn1 are imported to order.
Sheet is generally available in half-hard (H) temper in 0.5, 0.8, 1, 1.5, 2, 3, 4, 5 and 6 mm, with 1 to 3 mm being the common stock in Cairo and Dubai. Sheets are 1,000 x 2,000 mm; larger formats are special order.
| Grade | Composition | Thickness cut (mm) | Typical use |
|---|---|---|---|
| CuZn37 (CW508L, 2.0321) | 63% Cu, 37% Zn | 0.5 to 6 | Signage, screens, decorative panels, bent parts |
| CuZn39Pb3 (CW614N, 2.0401) | 58% Cu, 39% Zn, 3% Pb | 1 to 6 (plate) | Machined blanks, gauge plates, fittings |
| CuZn30 (CW505L) | 70% Cu, 30% Zn | 0.5 to 3 | Deep-drawn and spun parts |
| CuZn39Sn1 naval brass | 60% Cu, 39% Zn, 1% Sn | 2 to 6 | Marine hardware, coastal fittings |
Cutting parameters and edge quality
Brass needs about 1.5 times the laser power of mild steel for the same thickness: a 3 kW fiber cuts 3 mm comfortably, 6 kW is needed for clean 6 mm. Nitrogen at 12 to 18 bar keeps the edge bright; oxygen gives a faster cut but a dark oxide edge that must be cleaned before plating or lacquering. Kerf is 0.15 to 0.25 mm. Below 1 mm, brass cuts with almost no burr; from 3 mm upwards a small adherent burr of 0.1 to 0.2 mm appears on the underside and is removed by belt deburring.
Because zinc vaporises at 907 °C, the cut edge is slightly zinc-depleted and shows a reddish tint 0.05 mm deep. It disappears with light polishing and does not affect plating adhesion.
| Thickness (mm) | Min laser power | Kerf (mm) | Tolerance | Edge Ra (µm) |
|---|---|---|---|---|
| 0.5 to 1 | 2 kW | 0.15 | ±0.05 to ±0.1 mm | 1.6 to 3.2 |
| 1.5 to 3 | 3 kW | 0.2 | ±0.1 mm | 3.2 to 6.3 |
| 4 to 6 | 6 kW | 0.25 | ±0.15 to ±0.2 mm | 6.3 to 12.5 |
Design limits for brass parts
Minimum hole diameter is 1x thickness and minimum slot width the same; decorative screens with 2 mm bars in 3 mm sheet are feasible but distort slightly from heat, so keep bars at 1.5x thickness or accept 0.3 to 0.5 mm waviness. Sharp internal corners get the kerf radius (0.1 mm); for a truly sharp inside corner add a small relief. Brass letters below 30 mm height in 1 mm sheet should be nested with tabs so they do not fall through the grate.
- Minimum hole 1x t, minimum bar between holes 1.5x t for flatness
- Letters and logos: minimum stroke 1.5 mm in 1 mm sheet, 3 mm in 2 mm sheet
- Micro-tabs of 0.3 x 0.5 mm hold small parts in the sheet; specify if not acceptable
- Bending CuZn37 H: 1t inner radius, springback 2 to 3°
- Engraving with the same laser possible at low power for part marks
Finishing brass in a hot, humid climate
Uncoated brass tarnishes to brown within weeks in Gulf humidity and within days in the salt air of Jeddah or Dubai Marina. Interior decorative parts are polished then clear-lacquered (20 to 30 µm acrylic or 2K polyurethane); exterior parts are better electroplated (nickel plus gold-tone PVD, or chrome) or deliberately patinated. Antique and brushed finishes hide fingerprints and are preferred for hotel and mosque work. Dust in Riyadh and Cairo scratches high-gloss finishes, so satin is the practical choice for anything below eye level.
What to send
Send a DXF in millimetres with closed polylines, one part per layer or file, text converted to outlines, and the sheet thickness and grade in the notes. For decorative screens, state the visible face; brass shows a slight difference between top and bottom edges. If plating or lacquer is required, add it to the notes so the supplier orders nitrogen cutting and handles the parts with film.
Design tips
- Choose CuZn37 (CW508L) for anything decorative or bent; CuZn39Pb3 only for machined blanks.
- Keep decorative bars at 1.5x sheet thickness or more; a 3 mm sheet screen should have 4.5 mm minimum bars.
- Design letter strokes at 1.5 mm minimum in 1 mm sheet and 3 mm in 2 mm sheet.
- Specify nitrogen cutting for parts to be plated or lacquered; oxygen edges need cleaning.
- Add 0.5 mm to hole diameters that must accept M-thread bolts, since brass is not oversized like steel.
- For outdoor parts, specify plating or lacquer on the drawing; bare brass tarnishes in 2 to 4 weeks in Gulf humidity.
- Nest small letters with 0.3 x 0.5 mm micro-tabs; state if you need a clean edge without tab witness marks.
Applications
| Industry | Example parts | Typical material |
|---|---|---|
| Signage | Cut letters, logos, plaques, wayfinding | CuZn37 1 to 3 mm, polished and lacquered |
| Architecture and interiors | Mashrabiya screens, elevator trims, door plates | CuZn37 2 to 4 mm, brushed or antiqued |
| Hospitality and religious | Lanterns, mosque grilles, hotel fittings | CuZn37 1.5 to 3 mm |
| Electrical | Busbar tabs, earthing plates, terminal strips | CuZn37 2 to 5 mm, Cu-ETP for high current |
| Plumbing and HVAC | Gaskets, valve plates, nameplates | CuZn39Pb3 2 to 6 mm |
| Instruments | Dial plates, gauges, escutcheons | CuZn37 0.5 to 1.5 mm |
Pricing and lead time
Brass laser cutting cost is driven by material (CuZn37 sheet costs roughly 6 to 8 times mild steel and 2 to 3 times 1.4301 stainless per kg, so nesting efficiency matters more than on any other sheet metal), cutting time (brass cuts 30 to 50% slower than steel at the same thickness and consumes nitrogen), and finishing (polishing, lacquer or plating can equal or exceed the cutting cost on decorative work). Cut-only parts from stock 1 to 3 mm sheet ship in 3 to 5 working days; polished and lacquered or plated parts run 7 to 12 working days.
Frequently asked questions
Fiber lasers with back-reflection protection cut brass routinely up to 6 mm. The old problem was with CO2 lasers. The cut edge is clean with nitrogen assist and slightly darker with oxygen.
Upload your DXF, state the brass grade, thickness and finish, and receive a binding quote from CutLinq within 12 hours.