toolcraft AG, Georgensgmünd, Germany, has shared details of how it employs OpenARMS, a product from BCT Steuerungs- und DV-Systeme GmbH, Dortmund, Germany, to precisely adapt tool paths for the machining of metal additively manufactured components. Using this near-machine solution, the company explained that it is able to carry out automatic, adaptive post-processing; an important feature for any AM workflow to be fully industrialised.
During Additive Manufacturing, the use of a laser can cause thermal stresses in the part which lead to distortion. Despite process simulation, this can result in extremely slight deviations between the CAD model (target state) and the actual AM component (actual state). Ideally, these must be compensated for on each individual component before the subsequent machining process.
Using machine-integrated measurement technology and advanced algorithms, the OpenARMS software from BCT GmbH automatically combines the coordinate systems of the actual component, the target NC paths and the milling machine.
First of all, the tool path is automatically aligned to the position and orientation of the individual component by means of a rigid body transformation. In this way, distortions and deviations can be ideally compensated for during clamping. This means that the machining process is precisely adapted to the real conditions and there is no need to manually align the component on the milling machine. Functions such as the definition of mutual dependencies among several functional surfaces ensure compliance with tolerances while also reducing waste.
In the area of high-precision manufacturing, an absolutely transition-free machining surface must be provided for the additively manufactured geometry. In addition, auxiliary elements may be additively manufactured on the component’s surface for clamping in the milling machine. ‘Geometric adaptation’ functions are also available in the OpenARMS software. These not only allow the position and orientation of the machining programme and the component to be coordinated, but also enable the course of the milling path to be adapted to the component.
As a result, additively manufactured components are further machined to a higher quality and there is no need for further finishing steps. This means that the manual finishing of residues on free-form surfaces is no longer necessary. “With all this, toolcraft is meeting numerous customer requirements and taking another important step towards the industrialisation of Additive Manufacturing,” explained Christoph Hauck, Chief Technology and Sales Officer at toolcraft.
Rigid body transformation and geometric adaptation are already in use in high-precision manufacturing at toolcraft. The company will step up its partnership with BCT in order to jointly develop additional function modules for the automated further processing of additively manufactured components.
The aim is to ensure a continuous process chain and to reduce or, at best, completely avoid manual intervention. As part of the IDEA development project (Industrialisation of Digital Engineering and Additive Manufacturing), BCT and toolcraft AG are continuously working on advancing the industrialisation of AM.