Additive or subtractive – this is the decisive question!
Creative production optimization by intelligently combining CNC machining, additive production techniques and know-how transfer
History of toolcraft AG: The power of innovation to achieve rapid growth
Leveraging its impressive force of innovation, toolcraft AG combines CNC precision machining, additive manufacturing, CAD/CAM programming, special technical support – to name just a few.
The company, founded in 1989, provided job shop machining services for its clients, and soon afterwards it also addressed the need for technical support relating to production-ready design and process optimization. toolcraft quickly expanded and also actively promoted workpiece programming supported by CAD/CAM software: unicam Software GmbH was founded as distributor, consulting and training partner for the Mastercam CAM solution. The new head office in Georgensgmünd was inaugurated around the turn of the millennium, and today, there are more than 400 employees at this facility with an area of close to 20,000 square meters.
Additive manufacturing experience since 2011
Reflecting their claim to be innovation driver, they invested in new technologies at an early stage: In 2011, the new Additive Manufacturing business area opened, which in the meantime has a machine park of 12 systems. The powder bed technique has been certified according Nadcap since 2017 – clearly underscoring their ambitious objectives.
In 2020, a TRUMPF TruLaser Cell 3000 for powder laser deposition welding was purchased, and since then the project manager for additive manufacturing, Florian Schlund together with Jonathan Krauß have been heading up the team in the powder nozzle area. This involves the overall process from order entry, through programming, job planning, production up to quality testing.
Additive or subtractive manufacturing? – a defined decision-making process
Whether subtractive or additive, toolcraft carries out a feasibility study for every workpiece. The complete component lifecycle is taken into consideration, because: With deposition welding, areas of a part subject to high stress levels can be coated in such a way that wear resistance is improved many times over, which reduces the risk of failure of the customer's system.
This means that a customer receives a fair and well-founded statement regarding the technical feasibility of an additive manufacturing approach, the benefits and the costs to be expected.
Example of laser metal deposition – extruder worm with hardened surface
The extruder worm shown is a good example. The component repeatedly caused system failures as it wore quickly due to high load levels. Machining the extruder worm completely out of a hard material is not cost effective. In this case, coating the flights of the worm represented the optimum solution, while the basic extruder worm shape is still machined conventionally. Using the TRUMPF system, coatings between 0.05 and 3mm can be applied, which reduce the wear of this crucial part.
Machining and additive manufacturing: standard operation and programming
Florian Schlund is a qualified machining technician, and up until 2019 he operated various conventional machine tools at toolcraft. This is when he really got to appreciate the Sinumerik 840D CNC. The TRUMPF TruLaser Cell 3000 is also controlled by a Sinumerik 840D: "I really feel at home in this environment," explained a grinning Florian Schlund.
Switching over NC programming from conventional machining to additive manufacturing was far less complex than he had ever expected. Once you have mastered the process, such as production planning with CAD/CAM, setting up the clamping, selecting the zero point and working with the CNC, the switch to additive manufacturing is really quite straightforward.
Generally, it does not make economic sense to fabricate a mold for an individual part. As a consequence, complete additive manufacturing is the recommended approach for individual parts or small series. Deposition welding is also a good choice when it comes to subsequently modifying an existing module or assembly, such as attaching additional reinforcing struts and elements.
Defective parts frequently have to be repaired as part of maintenance work carried out on customer systems. In a first step, a line scanner identifies a defect. Using reverse engineering, the original component is then designed using the Siemens NX CAD/CAM software and the tool paths for deposition welding are planned.
Laser metal deposition (LMD) is then used to repair the defective location.
Patented high speed technique
toolcraft uses the EHLA high-speed laser metal deposition – a patented technique developed by the Fraunhofer Institute for Laser Technology Aachen. An additional EHLA deposition head integrated in the TRUMPF machine increases the previous deposition rate using the standard technique from a maximum of 2.0 meters per minute to an impressive several hundred meters per minute. Currently, EHLA can only be used for components that are symmetrical around their axis of rotation.
Seamless CAM system simplifies combining additive and cutting techniques
Depending on what a customer has specified, it may be necessary to finish parts on a conventional machine. If a conventional machining environment is available, which is the case for toolcraft, then the production workflows can be perfectly combined. The model of the part is completely available in the NX CAM software, so that the machining program with the tool paths required can be generated with low associated overhead.
AMbitious – a dedicated company for the transfer of know-how gained over decades
For some time now, toolcraft has also been a competent partner in the additive manufacturing domain. Already back in 2017, the original idea of holding seminars for customers' designers to help them clearly understand the special requirements of additive manufacturing – which ultimately saves time and money – finally matured. This original idea was transitioned into a new business area. Today, under the name AMbitious, a motivated team of professionals provide consulting services, support and training along the complete additive manufacturing (AM) process. toolcraft also supports startup companies and people changing career paths as they become acquainted with AM techniques.
The idea behind AMbitious is that customers do not have to repeat the same mistakes that toolcraft made when introducing additive manufacturing technologies. From selecting and installing the machine, through environmental aspects, selecting the correct material up to job planning and programming parts: Each and every question is answered and the appropriate training provided.
Florian Schlund sees this strategy as a model for success: Every customer inquiry demands a creative rethinking process and new impetus – and even makes toolcraft rethink established workflows.
The partnership with Siemens is a basis for the success of AMbitious. The NX software is attractive as a result of its functional seamlessness along the complete process chain. Irrespective of whether design, powder bed production, deposition welding or conventional machining: Just one system can master all of these tasks. AMbitious is reseller of NX software and provides the appropriate training courses – and as expert partner, introduces new requirements from the field into the collaboration with Siemens.
In any case, Florian Schlund is brimming with new ideas: New projects, including the use of robotics in the additive manufacturing domain, are already in the planning phase. The appropriate solutions have already been created in NX – a great basis for a successful project!
From the CNC4you magazine, edition 2022-2