By cutting so-called bending cut geometries or ‘kerf cut’, rigid sheet materials such as wood or acrylic can be bent. There are a variety of different shapes and geometries which result in different flexural behavior. We have tested different materials, such as wood and acrylic from 3 to 5 mm, and selected a few for you. Here you can find the appropriate graphic templates to download.
Kerf 1: Straight cut lines
Straight cut lines form a stable radius. The further apart the individual cutting lines are, the larger the bending radius. Depending on the graphic and material, a distance of up to 0.5 mm between the lines can be selected.
Kerf 2: Small waves
The small waves are interconnected and make the material look flexible. This cutting technique is suitable for materials up to 3mm thick. The bending radius is very large here.
Kerf 3: Large honeycombs
With the large honeycombs, the curves are tapered at each end and cut out of the sheet. This cutting pattern is often used in model making. Due to the large honeycombs, wooden boards up to 5mm thick can also be used flexibly.
The honeycombs can be easily pulled apart and pressed together and these properties can be combined easily with connections, for example, with bracelets.
Kerf 4: Wavy cut line
Like pattern 1, this cutting pattern consists exclusively of cut lines, but it differs in the bending properties, because it is much more flexible.
Kerf 5: Honeycombed cut line
The specially arranged pattern of this bending cut allows flexibility in all directions. This makes numerous creative applications possible, for example, in bag design.
Kerf 6 and 7: Narrow and wide waves
These cuts are all-rounders and work well with many different materials. The shape of the individual cut lines gives stability and flexibility.
Kerf 8: Triangular shape
This cutting pattern can be bent in all directions and due to its design, the pattern is often used as a graphic element.
The triangular shape of this cutting technique is very suitable for materials up to approximately 3mm. From 5mm material thickness, the bend becomes rigid and inflexible.
Wood is generally excellent for cutting techniques with bending applications. However, be mindful of the type of wood that is used. Accordingly, the following distinctions must be observed:
Plywood is very suitable for the use of bending applications. By gluing the sheets, the wood becomes very flexible in all directions and can be bent in a very narrow radius.
- Solid wood
For solid wood boards with a material thickness from 5 mm, cutting techniques for bending applications with recesses, such as Kerf 6, are much more flexible than a straight cut or a cut without a recess (Kerf 1). Here, it is very important to always cut in the direction of the grain. If the cut lines are across the grain, flexibility is reduced and the wood breaks more easily.
Like plywood, MDF is very easy to work with. Due to the mixture of grains, it is not necessary to align the cut lines.
Cutting techniques associated with acrylic are best for rigid bends, e.g. boxes or cases where the bending radius is very rarely changed. With a continuous load of the cutting pattern, e.g. with a book, the webs can easily break.
When processing acrylic, the following points must be observed:
- Use at least a 2" lens for the bending cuts. Given that the acrylic melts, if the lens focal length is too small, it may cause the cut area to instantly stick together again.
- We recommend a cutting distance of approx. 1 to 1.5 mm. If the material melts despite the correct lens being selected, increase the distance between the individual cut lines. However, if the selected distance is too large, the flexibility of the bend will decrease.
Important points for your desired bending result:
In summary, the following points must be observed when creating the design:
- Material properties
- Direction of the grain
- Distances of the cuts
- Material thickness
If you have any further questions about material processing or other laser applications, please contact us. Our laser experts will be happy to help you. In addition, the Trotec Academy offers training courses for various laser technology topics. We would be happy to arrange an appointment with you.