Laser engraving is a computer-driven, environmentally friendly alternative to mechanical engraving, chemical etching, milling, and many other costly, lower quality processes. In recent years, laser technology has proven to be a viable source for mold engraving as many traditional engraving methods have failed to meet the continually growing standards for precision, depth, and quality.
Laser marking and laser engraving technologies are emerging in the moldmaking industry for use in machining mold cavities. Mold makers know that machining small cavities in molds is difficult and time consuming, and extensive hand polishing is usually needed to complete the job. The task is made more difficult if the mold has already been hardened or made from pre-hardened steel.
Deep laser engraving provides an alternative non-contact machining process that is effective on hardened tool steels and able to access difficult to reach locations. It complements traditional CNC milling and electrical discharge machining (EDM) processes.
Deep laser engraving is generally considered to be a machining process that removes up to 30 thousandths of an inch of material. It is frequently used to add detail to molds such as patterns and features or to add identification marks. It's different from laser marking in that material is removed from the surface of the material.
Laser engraving uses higher powered fiber laser systems that are typically used for laser marking and engraving. The system uses engraving software as well as a range of motion control devices for precise control, and has the ability to engrave flat and contoured surfaces.
Mold Cavity Deep Laser Engraving
The major benefit of laser engraving solutions is that it will work wherever there is line of sight to the point to be marked. If you need to put identification marks at the bottom of a tool for making a plastic pin, it’s a relatively simple task to mount the mould in the laser and make the laser engraving. Deep laser engraving can be used for small and complex parts that are impossible to reach with mechanical engraving equipment.
A significant benefit of using lasers for engraving moulds is that it works equally well on hardened steel surfaces. In this context, it has similar properties to EDM, also known as spark eroding. However, it's generally faster, easier to set up, and requires no expensive consumables such as electrolyte and electrodes.
On the other hand, if the volume of material to be removed is significant, then conventional CNC milling may be faster and or more effective.
Deep laser engraving can reduce costs and expand the scope of work performed by tool and die makers. Some of the benefits of laser engraving include:
Replace milling and EDM machines: Laser engraving can replace conventional machining methods for small cavities and reduce overall mould costs.
Long life: Laser components last longer and require less maintenance than EDM and CNC milling machines.
Surface finish: Laser engraving gives a better surface finish that usually does not require hand polishing.
Heat-affected zone: Laser engraving has a lower impact on the surface hardness of moulds and avoids the risk of micro-fracturing that exists with EDM.
Cost: Running costs are much lower.
Versatility: Mark and engrave logos, any type of alphanumeric writing, barcodes, progressive numbers, designs, data matrixes and graphics, from the most simple to the most complex.
Traceability: Product traceability is forever guaranteed, since laser marking on metals is permanent and resists both wear and contact with acids or heat.
High Definition: It can create small, detailed geometric shapes with the utmost precision. You can combine marking processes to clean the material after processing or to give the marking greater contrast (e.g. Data Matrix codes).
Speed: Laser marking is a fast process offering unparalleled quality, it allows creating different types of markings (e.g. serial numbers, logos, codes) in extremely short timeframes without having to re-fit the machine.
Seamless Markings: On many types of metal it is possible to achieve completely seamless and indelible markings: the tone is in fact achieved not via removal but rather through localized heating of the material.
Efficiency: It does not involve any costs for consumables such as inks, pastes or sprays and no costs for their expensive disposal. No prior or subsequent treatment is required. The equipment has no wear and tear problems.