Copper laser cutting

The 12 kW source is what makes production copper cutting practical; a lower-power machine cuts slowly and produces dross. Edge quality improves with nitrogen and a clean nozzle, and pierce time has to be extended to avoid damaging the optics. Burr on copper is soft and can be removed easily, but it must be removed before plating or coating.

The commercial consequence is that copper is priced on its own material line, not blended into a steel rate. Material grade, thickness, tolerance and finish are quoted separately from conversion, so a change of specification is visible in the price.

Ganesh quotes to the drawing first and to ISO 2768 general tolerances where the drawing is silent. For copper laser cutting, the practical starting points are in the table below. They are starting points, not a guarantee: the part geometry, thickness and fixturing decide what can actually be held, and the quotation states the tolerance offered.

Cut quality depends on assist gas, focus position and nozzle condition more than on the headline power; nitrogen gives an oxide-free edge on stainless and aluminium. Busbars and current-carrying parts are specified by conductivity, not just by grade name; ETP C11000 is the common baseline and oxygen-free copper is reserved for vacuum or brazing duty. The route is quoted as one sequence so the customer does not have to coordinate a cutter, a former, a welder and a coater.

Where a busbar needs a rolled, radiused edge or a coined profile, laser cutting alone will not produce it; a press or a machined edge is required.

A manufacturability review before quotation is the cheapest place to find this out. Send the drawing, material, finish and annual quantity and the review comes back in writing.

• Busbars and links
• Heat spreaders
• Shielding
• Terminal plates

Use laser cutting when the design is still moving, when the volume does not justify a tool, or when the part is large enough that a press tool would be uneconomic. It is also the right first operation for a part that will be formed and welded, because a nest can carry several different parts at once. It stops being the cheapest route when a flat part with stable geometry runs in high volume, at which point a blanking die wins on piece price and generally on edge quality too. For copper the practical constraint is conductivity and heat: cutting parameters, bend radius and joint method are all set by the temper and the electrical requirement, not by the shape alone. Copper parts are often single-source by specification rather than by process, so the decision that matters is the temper and the edge condition, both of which should be on the drawing before a supplier is chosen.

Send a DXF with the cut contour on its own layer, no duplicate or open entities, and a drawing that states material grade, thickness, tolerance and finish. State which edges are cosmetic and which are weld prep, because the assist gas and the deburring requirement follow from that. If the part is long, say the maximum length: a 4,450 mm panel that fits the 40 ft bed in one piece does not need a joint.

Inspection covers the cut contour against the DXF, overall size, hole position, squareness and edge condition. Burr is checked visually and by touch on cosmetic edges. Material is traceable to the mill certificate where the customer requires it. First article parts are inspected before a repeat run.

Cost splits into material, machine time, handling, deburring and any secondary operation. Material is quoted at the prevailing rate for the grade and thickness, on the nest area consumed rather than the finished part area. Machine time is set by cut length, thickness, pierce count and nesting density. Deburring is a separate operation and is often the line that surprises a buyer. On copper, material is quoted as its own line at the prevailing rate for the grade and thickness, so a change of specification is visible rather than hidden in a blended rate.