Rigid sheet materials, such as wood and acrylic, can be bent using a laser cutting technique known as a kerf cut. When a variety of shapes and geometries are utilised, different flexural behavior results. The laser cutting technique has been tested on a variety of materials, including wood and acrylic from 3 to 5mm. Find out more by downloading our graphic templates.
Kerf 1: Straight cut lines
By cutting straight lines, a stable radius will be formed. As the individual cutting lines grow further apart, the bending radius will also become larger. A distance of up to 0.5mm between the lines can be selected however this depends on the material that you are using.
Kerf 2: Small waves
The material will appear flexible as the small waves are all interconnected. Materials up to 3mm thick are suitable for this cutting technique. Here, the bending radius becomes very large.
Kerf 3: Large honeycombs
When utilising large honeycombs, curves are tapered at each end and cut out of the sheet. This cutting pattern is commonly associated with model making. Wooden boards up to 5mm thick can be used flexibly given the large size of the honeycombs. The honeycombs can be easily pulled apart and pushed back together. These properties enable honeycombs to be easily combined with connections.
Kerf 4: Wavy cut line
Like with Kerf 1, this cutting pattern comprises entirely of straight cut lines. However, its bending properties do differ substantially given that it is more flexible and sturdier than Kerf 1. It can therefore be used for a wider range of applications.
Kerf 5: Honeycombed cut line
You will be able to achieve fleixibility in all directions with this specially arranged bending pattern. Laser cut bags are one of several creative applications that are possible.
Kerf 6 and 7: Narrow and wide waves
These two cuts are all-rounders and work with almost any application and material. The individual cut lines have a unique shape that provide additional stability and flexibility.
Kerf 8: Triangular shape
This cutting pattern can be bent in all directions and provides a unique and aesthetic design. The triangular shape of this technique makes it suitable for materials approximately 3mm in thickness. Materials thicker than 5mm will experience a rigid and inflexible bend.
While wood is generally a great material to use for cutting techniques with bending applications, you must be mindful of the type of wood you are using. The following distinctions must be observed:
Plywood is suitable for the use of bending applications. By gluing the sheets, the wood becomes very flexible in all directions and can be bent at a a very narrow angle.
- Solid wood
When using solid wood boards with a material thickness of 5mm or above, cutting techniques with recesses (Kerf 6) provide greater flexibility than a straight cutting line pattern (Kerf 1). Here, it is very important to always cut in the direction of the grain. The wood will break more easily and flexibility will be reduced if the cut lines are across the grain.
MDF is very easy to work with just like plywood. It is not necessary to align the cut lines due to the mixture of grains within the wood.
Rigid bends are best achieved with cutting techniques involving acrylic, e.g. boxes or cases where the bending radius is very rarely changed. With a continuous load of the cutting pattern, for example with a book, the webs can easily break.
When processing acrylic, the following points must be observed:
- For the bending cuts use at least a 2" lens. Given that the acrylic melts, it may possibly cause the cut area to instantly stick together again if the lens focal length is too small.
- A cutting distance of approximately 1-1.5mm is recommended. If the correct lens is selected and the material still melts, increase the distance between the individual cut lines. If the selected distance is too large, however, the flexibility of the bend will reduce.
Important points for your desired bending result:
When creating the design, consider the following points:
- Material properties
- Direction of the grain
- Distances of the cuts
- Material thickness
Please contact us if you have any further questions regarding material processing or other laser applications. Our laser experts are always happy to help. The Trotec Academy also offers training courses for various laser technology topics. We would be happy to arrange an appointment with you.