Laser wood engraving is exactly what it sounds like: using a laser to put images onto wood surfaces. While this may seem very simple, it isn’t as straightforward as it appears. Different woods require different laser temperatures and power in order to properly engrave. In addition, slight variations in the wood can easily cause imperfections or may make the wood catch fire. In general, harder wood is easier and more consistent when laser wood engraving; soft wood is much more difficult and composite wood surfaces are highly erratic.
Specialized machines, designed to work solely on wood, perform the majority of laser wood engraving. There are two main types of machines. Some are machines that use common manufacturing process code, called computer numerical control (CNC), and require specialized training both to code and to operate. The others work more like a computer printer. These machines require a lot less knowledge to use, but they often lack some of the versatility found in a CNC machine.
One of the largest challenges of laser wood engraving is the wood itself. Hardwoods, such as maple or mahogany, work the best. The material of these trees is both solid and consistent throughout the wood. This means that, as the laser burns down into the surface, the strength of the wood doesn’t change. If the wood were to become harder, the laser would lack the power to properly engrave; if it were softer, the laser would cut far too deep.
Softwoods provide more of a challenge for laser wood engraving. These woods, such as pine, are less uniform than hardwoods. The grain of the wood may change and the relative strength of the material is more likely to change as the laser cuts into the wood. This causes problems such as poor quality engravings, small fires or even vaporizing portions of the wood. It is for this reason that most laser engraving done in pine doesn’t penetrate far into the surface.
There are many common uses of laser wood engraving. In manufacturing processes, such as making embellishments on wooden furniture, the use of lasers is preferred over conventional techniques. The laser creates less waste and is usually much faster than physical engraving. In addition, the lack of physical contact between the work piece and the laser means there is significantly less wear on the machine, so it costs less to maintain.
On a more artistic level, it is possible to depict nearly anything in a laser wood engraving. Since these processes are controlled by a computer and cut by a laser, the fine detail available is far beyond what is possible with physical carving. This means that things such as photographs or paintings can be transferred directly to the wooden surface with no loss of detail.