For all of the versatility of the laser, different materials react in different ways to the engraving process.



Wood and Paper

One of the first uses of laser engravers was to burn designs into wooden surfaces. The wood burns easily so can be engraved by low-wattage lasers. Hardwoods such as oak or mahogany work best. Softer woods can produce inconsistent etching depths and have been known to actually ignite during the etching. Use of the lowest wattage lasers is recommended for these projects.

Fiberboard and hard paper work very well with laser engraving. Linty papers and newsprint tend to respond like soft woods.

Plastics

Acrylic is one of the most common plastics used with laser engravers. It holds the etch well and produces a breathtaking finished piece. Other successful plastics include Bakelite and similar hard plastics.

Softer plastics, such as styrene, tend to melt around the engraving producing a softer or even deformed look. This might be acceptable or even desired depending on the purpose of the engraving.

Special plastics have been developed specifically for laser engraving. These may include silicates to help keep the heat of the laser from melting excess material, or may be layered so that etching away the surface reveals colored layers below.

Many plastics such as vinyl or silicones simply don't work with laser engraving and require other methods.

Metals

Standard metals require specific, short-wavelength lasers and therefore don't work in most laser engravers. However coated metals perform quite well since, rather than vaporizing the metal, the lasers vaporize the coating to reveal the metal underneath. Common examples include painted brass and anodized aluminum.

Stone and Glass

Stone and glass are difficult to engrave with lasers and are often better served by other engraving techniques. However when used successfully, laser engraving creates a distinctive pattern of tiny fractures that produces beautiful and durable pieces. Granite is a particularly successful medium since once it is successfully engraved, its durability means it will last for decades even if used for applications like floor tiles.

Glass is also commonly used with sub-surface laser engravers. These engrave the image under the surface of the glass, often in three dimensions, to create stunning keepsakes that other engraving methods can't equal.

Other Materials

Laser engraving is often used successfully with leather, producing a burned look that resembles hot branding. Latex rubber is also an effective material and laser engravers are often used to make rubber stamps.