Whether you are an operator or an experienced engineer, it is possible to avoid certain mistakes and pitfalls by learning the proper use of your laser engraver machine. In the field of laser engraving, designers often commit some common mistakes that can be avoided without much of an effort. Mentioned below are some of these mistakes and the ways to avoid them.
In many instances, the fabric is engraved by the machine, but the laser tends to burn through the material. In order to avoid this problem, it is important for you to understand the process and temperature that the fabric can withstand. Fabrics such as leather, canvas, and denim can withstand higher power settings. However, if the fabric is delicate, you should start the settings at low power and high speed. Use some spare material to test these initial settings. You may increase the power later on if the fabric is able to withstand the initial settings. During direct-to-garment engraving, lowering the DPI or dots per inch at which engraving is done can be helpful. If the DPI is higher, the amount of material removed will also be more. Low DPI engraving will ensure that the top layer just gets vaporized and there is no complete burning through the fabric. Engraving at 150 to 300 DPI is suitable for most fabric types.
Often times, people fail to produce a frosty white engraving with acrylic. Most commonly, this is the result of using the wrong type of acrylic. Cast and extruded acrylic are the two types of acrylics used in laser engraving. Cast acrylic sheets are considered to be the perfect fit because when engraved, they deliver a frosty white color. However, it can’t provide flame-polished edges. On the other hand, extruded acrylic reacts differently to laser engraver machines. They provide flame-polished edges and cut smoothly and cleanly. However, extruded acrylic can’t provide a frosted appearance. Therefore, if a frosted white finish is required, you must use cast acrylic.
Inconsistent glass engraving is another common problem reported by many people. In many instances, the glass surface is fractured when it is struck by a laser but deep or complete engraving is not accomplished. A frosted appearance is produced by the fractured glass surface. However, depending on the type of glass you are engraving, the surface can get chipped and rough. Though the frosted look is desirable for laser engraving, a rough or chipped surface is extremely unfavorable. Some ways to create a frosted, as well as smooth finish, are using a lower resolution, running the engraver with Jarvis Dithering, using 80 percent black in the graphic, applying a wet paper towel or newspaper to the engraving area, etc.
Wood engraving may produce different results even when the settings are the same. This is because different varieties of wood react differently to the laser engraving process. Cherry, maple and other light woods produce a nice contrast because the wood is easily burnt away by the laser. On the other hand, while using denser woods, cutting and engraving require more laser power. Depending on your choice of wood, its grain density can change significantly. Maple, alder, walnut, and cheery are known to have fairly small grains. On the other hand, medium to large veins is found in oak. Therefore, if you engrave a large square into a piece of cherry, the appearance is likely to be uniform without any significant variation in height. However, if the same engraving process is performed with a piece of oak, the appearance will be extremely non-uniform with lots of height variations. Therefore, for wood engraving, please remember that alder and maple are the most suitable types. Smoke and debris are produced during bare wood engraving. You may minimize this effect by engraving from the bottom up.