5 Common Mistakes in Laser Engraving and How to Avoid Them
Whether you are an accomplished engineer or a novice manufacturer just getting started, learning the proper use of design equipment can save time and effort by avoiding possible problems and errors.
From time to time, problems arise that leave designers wondering what they are doing wrong or how they can do it better. This is true in any field, and laser engraving is no exception.
Knowing how to avoid these mistakes and not repeat them is half the battle. With that in mind, let's explore the five most common mistakes in laser engraving and how to avoid them in future projects.
Mistake 1: The laser burns through the material when engraving fabric
The first step in avoiding burning through fabric when using a laser engraving/cutting machine is to know which fabrics can withstand the process and what temperatures the fabric can withstand. Stronger fabrics such as denim, canvas and leather can withstand somewhat higher temperatures when engraved. However, for softer fabrics, it is most important that the initial settings be fast (close to or equal to 100%) and low power (about 5% to 10%). Test these initial settings on some alternate materials to see if the fabric can withstand engraving with these settings and gradually increase the power until you get the results you want.
When engraving directly on the garment, lowering the dots per inch (DPI) of the engraved area will help the engraving. the higher the DPI, the more material will be engraved off. Engraving at a lower DPI will ensure that the laser only slightly evaporates the surface material and does not burn through the fabric completely. Keeping the DPI between 150 and 300 is good for engraving most fabrics.
Mistake 2: Acrylic material can not be carved out of frosted white effect
This is most likely due to the use of the wrong acrylic material in the engraving application. There are two common types of acrylic materials used for laser engraving, and both are suitable for different applications.
Cast acrylic sheets and objects are made by pouring liquid acrylic into molds of various shapes and sizes. This type of acrylic is ideal for engraving because it turns frosted white when engraved and is suitable for medals. You can also use a laser machine to cut this type of material, but it does not create a flame polished edge.
Another acrylic material used for laser engraving is acrylic extrusion, which is a sheet made by machine. The price of acrylic extrusion sheet is usually lower than acrylic casting material because it is made through a mass production process. However, when this material is engraved using a laser engraving machine, it produces a very different result. This type of acrylic material cuts very cleanly and smoothly and produces a flame polished edge. But instead of a frosted white effect, the cut result is a fairly clear engraving pattern. So, if you want a frosted white finish, make sure you use cast acrylic material.
Mistake 3: Contradictory glass engraving
Typically, the laser striking the glass will break the surface, but will not go deeper into the engraving or remove the material needed for complete engraving. The broken glass surface will produce a frosted appearance, but depending on the type of glass being engraved, it may be rougher and may be chipped. While a frosted appearance is the desired effect, no one wants a rough or chipped engraved surface.
To produce a smooth frosted finish, try combining one or more of the following tips.
Using a lower resolution, about 300 DPI will produce better results on the glass when moving the engraving position.
Change the black in the graphic to 80% black.
Using the Jarvis dithering mode (found in the Epilog print driver) will help achieve a smooth finish.
Sometimes laying a thin layer of wet newspaper or paper towels over the engraving area will help dissipate heat and improve the quality of the engraving. However, make sure that the paper is not wrinkled after being laid on.
Another way to dissipate heat is to wipe a thin layer of detergent on the engraving area with your fingers or a paper towel.
Finally, if there are glass fragments after engraving, please use a scratch-free Pasteurized cloth to wipe the engraving area clean.
Mistake 4: Wood engraving gives different results with the same settings
Wood is one of the most suitable materials for laser engraving because it is not only easy to cut, but also engraves very well.
However, different woods respond differently to laser engraving and obtain different results. Lighter woods such as cherry or maple produce very rich contrasts when the laser ablates away the wood, while higher laser machine power is required to cut or engrave stronger woods.
Depending on the type of wood you are working with, the grain density can change considerably. Cherry, alder, walnut and maple have a very tight grain, while oak has a medium to rough grain. For example, if you carve a large square in cherry, the resulting appearance will be very uniform, the carved area will be smooth and there will be less variation in height. However, if the same large square is carved into oak, the appearance will vary greatly in height and be very inconsistent in appearance.
Some tips for carving woods are provided below.
Maple and Alder are some of the most popular woods for carving and can create a rich contrast.
The process of carving bare wood produces smoke and debris that may become embedded in the grain of the wood. To reduce this effect, always carve from the bottom up, which helps to draw out all smoke during the carving process.
When carving stained wood, use a damp rag to wipe away excess smoke and debris from the surface of the wood after carving.
Mistake 5: The laser engraver can no longer run as fast as it used to
Clean your machine! Just like any other type of design equipment, a clean machine produces better results than one that has not been properly maintained. Your laser machine owner's manual contains maintenance requirements. If performance is dropping quickly, the first step in fixing the problem may be to inspect and clean the optics.
We recommend checking the optics (lenses and reflectors) in your laser machine weekly and cleaning them as needed. If you are cutting material that produces more residue, you may need to clean the optics more frequently. Typically, optics should be clear golden brown, bright and shiny. If they look fuzzy, or have smudges or debris, it's time to clean them.
The mistakes listed above are very common among manufacturers and designers who use laser engravers, especially those who are just starting to use these machines. But as you can see, with the awareness to correct mistakes, these problems can be easily avoided.
We help designers and manufacturers through every step of buying the right laser engraver, choosing the right materials, and understanding how to respond to common mistakes, including a library of knowledge base articles and helpful support for users who are experiencing challenges.