Joinery technology
With the transformation of timber construction, the processing of timber components has also changed; in order to achieve the required accuracy and processing quality, many woodworkers rely on numerically controlled processing machines (CNC). The new Holzbau AG in Lungern has also invested heavily in this area. A six-axis Hundegger portal processing system has been in operation since October 2006. With this machine, components up to 33 x 5 x 0.5 m can be processed. From August 2007, the system will be supplemented with a Hundegger Speedcut SC2 cutting center. This combination enables efficient, precise trimming of both large and small straight or curved timber components.
From CAD to the machine
A 3D CAD file forms the basis for generating machine data. This file is usually created in industry CAD software. In Switzerland, programs from Cadwork, Sema and Dietrich's are mainly used. The project planner assigns all components in the 3D file, including the desired machining operations (bores, tenons, taps, flats, dovetails, etc.). The software has a machine type-specific interface that automatically recognizes the components and the existing machining operations. The machine software in turn assigns the specified macros to the various machining operations (in Hundegger's case to the EKP individual design program). Once this process is complete, the bars can be reworked (if necessary) in the machine software and then machined with the CNC system. The individual software components have various additional tools such as optimization lists, sequence changes for visible components, nesting, etc.
As there are hardly any large series quantities in timber construction, it is extremely important that, firstly, the CAD interface and the machine program work very closely together and, secondly, that these two software components have a high level of intelligence of their own. Thanks to constant further development in the software sector, the entire timber construction industry has been given a great opportunity and countless possibilities. Thanks to these intelligent and sophisticated programs, it is now possible for timber construction to generate and process machine data from any number of different individual components in an incomparably efficient manner. In comparison, the programming effort of a CNC system used in steel construction is much greater, so that CNC-machined steel parts in small series (less than 30 pieces) are hardly worthwhile.
Hundegger plays a key role in the development of CNC processing systems for solid wood and the associated software. Without the pioneering spirit of this company, CNC joinery technology would certainly still be a long way from where it is today. The market share of Hundegger systems in the CNC joinery sector is around 80% worldwide. In addition to the construction of systems, the company also offers solutions for feeding, software, tools, consulting and service. This means that, in addition to the CAD software, the wood processor has only one contact person, which makes his work much easier. The interaction between Hundegger and the CAD software (in our case Cadwork) works very well. Together with these two partners, we hardly ever have a problem for which a solution cannot be found within a reasonable period of time.
CNC technology enables us to design in a completely different way. In contrast to conventional joinery, some complicated machining processes suddenly become very simple. The most popular example of this is the dovetail joint. Conventional joinery is very complex. However, as soon as the component is on the machine, this connection becomes almost unrivaled in terms of cost compared to other fasteners. It is now increasingly important to find such solutions for timber construction. For example, assembly parts that can be joined together using simple plug-in connections, or high load introductions with the smallest possible cross-section. Savings in assembly time or material, even if "complicated" processing of the wood has to be accepted.
However, it is not only complex components that become cheaper. With a clean and clear calculation, every timber construction company will quickly realize: With conventional joinery methods, it is hardly possible to process components at the same cost as with a CNC-controlled joinery system.
The processing of timber components using CNC technology opens countless doors and new paths for the industry. It is now up to individual timber construction companies to make sensible use of these advantages and, not least, to further increase the market share of wood as a building material. Many more incomparable, elegant buildings can be constructed and realized with the ingenious material of wood.