28 June 2016
The concept tool is a prototype of an advanced drilling machine that sets a benchmark about what can be achieved today through state of the art 3D printing in terms of development and manufacturing.
pd|z Our Mission
The product development group of the ETH Zurich (short pd|z) focuses on human-centered product development and regards the link between research and education as the key to excellence in training. We see ourselves as a partner for industry and promote the continuous transfer of knowledge through cooperation, as well as the training and further education of students and graduates to boost the competitiveness of the mechanical engineering industry in switzerland.
Concept Tool, the challenge
Today 3D printing is mainly used for rapid prototyping and specialised parts. The idea behind this project is to show the beneficial properties of 3D Printing as manufacturing technology for industrial use. The focus is on the product development process for additive manufactured parts illustrated by the example of a battery operated hammer drill.
The different sub-systems of the Concept Tool show the range of applications of 3D printing. The used 3D printing technologies are Selective Laser Melting (SLM) for metal components and Selective Laser Sintering (SLS) for plastic components. During the development process Fused Deposition Modelling (FDM) was used for rapid prototyping purposes to allow fast iteration cycles with functional models. The main internal systems of the tool are a suction system, a bearing structure and a cooling system. These systems illustrate the use for optimised flow channels and surface maximisation of cooling areas by applying complex geometry only achievable with 3D printing. The internal bearing structure is an aluminium framework holding the gear, sustaining all the forces, connecting the sub-systems and allowing the tool to be functioning without outer case. All these systems as well as the electronic parts are stored in the outer case. Additionally the case has to ensure the leak tightness and have an ergonomic shape. This multitude of requirements leads to complex parts with lots of integrated functions, highlighting another major advantage of 3D printing.
Our learnings from the project
With the realisation of three iterations the system could steadily be further developed. While the first prototype revealed some deficiencies in the main functions the final product works reliably and can easily keep up with the performance of conventional hammer drills. With electronic assistance systems for the borehole depth, the torque limitation and the positioning of the borehole as well as an ergonomic shape the Concept Tool is a convenient tool with concept character. In respect to 3D printing the main conclusions were that there are important constructive restrictions and that post-processing has to be taken into account from the beginning. Other important learnings were that the part quality depends on many parameters, that parts should be designed specifically for the planned 3D printing technology and that given specifications have to be applied with caution as they depend on the part geometry and many often uninfluenceable machine and process parameters.