Advanced Techniques
Rastering
Kerfing
Rastering is a process whereby the laser cutter traverses back and forward to gradually impart an image or hatched area onto a piece of material.
Basic raster outcomes are affected by how you adjust your speed, power, black & white threshold, and Dots Per Inch (DPI). This is particularly true with images that have high DPI.
Raster image quality is measured by pixel density. The more pixels per inch, the sharper an image will appear. Pixelation occurs when the number of pixels per inch in an image is low, causing each pixel to have visible edges. This distortion becomes worse as the image is enlarged.
Tracing bitmaps and converting them into vectors allows you to scale an image while avoiding pixelisation from occurring. Because vector images can be engraved as well, they typically work better for a custom basic raster. Vector images are the native format for Illustrator and vectorising images with those programs is an easy process using the Live Trace functions to create your design.
Once an image is vectored, it can be easily scaled and edited without pixelation.
The Black & White Threshold application replaces each individual colour pixel in an image, with a black or white pixel image.
In our laser software, colours other than black and white (including vector lines in the same design) will register as an engraving if the black and white threshold is not adjusted.
You can adjust the intensity toward black or white, but it is best to find a good contrast. If vector lines are present in your raster job, best practice is to make them a lighter colour, so they don’t register as a raster.
If they are still registering as an engraving, simply adjust the b/w threshold to remove the unwanted rastered sections.
When you submit a file to be rastered on the laser cutter, make sure the area to be rastered is a fill and is on the raster layer which is CYAN, this should be a blue colour.
Kerfing is a technique of patterned cutting, that allows the bending of rigid sheet materials including wood and acrylic turning a flat 2D surface to a 3D surface. Different patterns may produce different degrees and angles of flexibility.
While kerfing is an easy and useful technique for bending wood and acrylic, it is suited to applications where a curve is aesthetic rather than structural, such as model making, as kerfing does not create a form with great strength.
Straight Line Cutting is a good yet simple technique, which forms a sturdy and stable radius. The further apart the cuts are, the larger the bending radius will be. Depending on the graphic and material you are using, a distance of up to 0.5mm between each line can be designed.
Straight Cut Kerfing
The Small Waves technique consists of tiny, interconnected cuts that allows extreme flexibility to a material This cutting pattern is suitable for materials that are 3mm thick or less. The bending radius is very large here, which can be a desirable trait depending on your application.
Small Waves Kerfing
When using Large Honeycombs, the curves are tapered at each end and cut out of the sheet. This is a technique often used in model making. Wooden boards up to 5mm thick can be made very flexible. This is because the honeycombs can be easily pulled apart and pushed back together. These properties can also be combined with connections.
Large Honeycomb Kerfing
As with Kerfing Technique 1, this cutting pattern consists exclusively of straight cut lines. However, it does significantly differ in the bending properties created. It is much more flexible and slightly sturdier than Technique 1, so it can be used for a wider range of applications.
Wavy Cut Kerfing
The Honey Combed Cut Line arranged cutting pattern allows extreme flexibility in all directions, as opposed to just up or down. This can make numerous creative applications possible. For example, you can try your hand at creating some laser cut bags made completely from acrylic or wood. The sky is your only limit!
Honeycombed Cut Kerfing
These two cuts can work with almost any application and are appropriate to use with most materials. The shape of the individual lines supplies your work with a fair amount of stability and flexibility. You won't have to worry about your completed product breaking or over-stretching because the technique is quite sturdy and safe.
This technique is recommended when unsure which is appropriate for your current application.
Wide Waves Kerfing
Narrow Waves Kerfing
This is an effective and aesthetically pleasing pattern. It can be bent in all directions and the pattern tends to be used as a graphic element. The triangular shape of this technique is suitable for materials approximately 3mm in thickness or less. Thicker materials will become too rigid and inflexible to bend well.
Triangular Kerfing
Timber is generally a great material to use for these cutting techniques. However, be mindful of the type of wood you are using. The following distinctions must be observed:
Material | Capabilities and Limitations |
Plywood |
|
Timber |
|
MDF |
|
The cutting techniques that are associated with acrylic usually work best with rigid bends. This includes boxes or cases where the bending radius is very rarely changed (see the below image). With a continuous load of the cutting pattern, the webs can easily break.
Acrylic Kerfing
Last modified 1yr ago