Laser Cut Brass & Copper

Brass or copper?

Brass 260, also called cartridge brass, is copper alloyed with roughly a third zinc. It has a bright gold tone, polishes to a high shine and folds well, which is why it's the traditional metal for plaques, nameplates, trim and decorative hardware.

Copper 110 is nearly pure copper. It carries electricity and heat several times better than brass, which is why electrical parts are made from it, and its salmon-pink color deepens to brown as it ages. It's softer than brass, so it bends easily and dents easily too.

Both tarnish in open air, so decide early whether a part should keep its new color, which means sealing it, or age to a natural patina. Both also cost more than steel, which makes compact designs worth the effort — more on that below.

Plaques, signs and inlays

Most brass orders are plaques, nameplates, address numbers, sign letters and decorative panels. Wall plaques are usually thin sheet set with construction adhesive or standoffs through cut holes; cut-out letters and freestanding pieces want heavier sheet so they stay flat and resist dents. The signage guide covers letter design and outdoor mounting.

Lettering can be etched into the face or cut through. Etched text reads as a change in tone and texture, which works up close; for lettering that reads from across a lobby, cut the letters through and mount the plaque over a dark backer, or cut the letters as separate pieces and stand them off the wall.

Brass and copper inlays pair well with the router: cut the inlay on the laser and its pocket on the CNC router, drawn from the same outline with a little clearance for adhesive. A routed pocket keeps at least a 1/16″ radius in its inside corners, so round the inlay's corners to match, and cut a test piece before committing a tabletop.

Bus bars and electrical parts

Copper 110 is the usual choice for bus bars, grounding bars, battery straps and terminal links; brass conducts only a fraction as well, so keep it for hardware and trim rather than parts that carry current. Size a bus bar's cross-section for its current with your electrical engineer or the code that applies — the laser cuts the shape you draw, and the rating is up to the design.

Draw bolt holes at clearance size and keep them back from the ends so the bar doesn't tear out when the bolts are torqued; holes are cut, not tapped. Copper darkens as it oxidizes, which raises contact resistance, so clean the contact faces just before assembly, and send bars that need tin or silver plating to a plater after cutting.

Designing for the laser

The laser cuts all the way through the sheet, so draw outlines, cutouts, holes and slots — not pockets or partial-depth holes. Keep holes at least about half the material thickness across so they cut cleanly; the quote flags anything smaller before you order.

Lines you set to engrave are etched on the surface instead of cut through — handy for part numbers, logos and bend or layout marks.

Designing in brass and copper

Metal is billed by each part's outer size plus a little cutting space, and in metals that cost as much as brass and copper, a part's footprint matters. A ring, a long diagonal piece or an L-shape pays for the rectangle around it, so where the design allows, split a large ring or frame into segments that join behind the work, and keep decorative parts compact.

Thin brass and copper are soft, so leave delicate parts enough metal around their openings, and keep at least the material thickness between holes in a pierced pattern for a pendant, ornament or screen. Pieces under 1″ both ways may arrive held by small tabs to snap off and file smooth. Both metals fold readily into tabs, clips and small enclosures; add bend reliefs at the corners and etch the fold lines.

Brass and copper are sold by decimal thickness rather than gauge; the sheet metal gauge chart lists each thickness in stock.

Keeping the color, or letting it age

To keep the new color, a part is polished and sealed with a clear lacquer made for brass and copper, or waxed and re-waxed now and then. Skin oils leave fingerprints that tarnish first, so handle polished parts with clean gloves until they're sealed.

In the valley's dry air, outdoor copper browns evenly and takes many years to reach the green of a coastal roof, while brass darkens to a soft antique brown. Pool and spa chlorine darkens both quickly, sprinklers leave mineral spots, and a plaque in afternoon sun gets hot to the touch.

Artists speed the aging along with chemical patinas — liver of sulfur for browns and blacks, ammonia and salt solutions for greens and blues — and then seal the result. Polishing, lacquer and patinas are finishing steps for after cutting, done by a finisher or in your own studio.

What a brass or copper order includes

Brass and copper parts ship flat and as cut, in mill finish — not polished, lacquered or plated. Polishing, sealing, patinas, plating, deburring, bending and soldering or brazing happen after the parts leave the shop; for a finished installation, describe the job in a custom fabrication inquiry. Round, turned and cast pieces are covered in the questions below.

How it's priced

Each part is priced on its cut length, each hole by its size, its pierces and any etched lines, plus setup and programming once per design, handling for each piece and loading for each sheet the job uses. Metal is billed by the area your parts use — each part's outer size plus a little cutting space — never more than the sheets they're cut from, and identical parts get automatic quantity discounts on the cutting.