Founded in 2012, Kühling&Kühling sells its customers flexible and easily scalable 3D manufacturing solutions. For the realisation of the first series-produced 3D printer, the Kiel-based solution expert was looking for an energy chain for safe cable routing and a suitable liner bearing solution. The demands of a 3D printer on the bearing technology are high: the high performance of the machines requires moving components that can withstand high accelerations over a long period of time without any problems and with as little maintenance as possible. In addition, the dynamic inner workings also result in enormous temperatures of up to 80 °C, for which the right materials had to be found. Finally, the built-in parts also had to fulfil the high requirements in terms of quietness.
The company Kühling&Kühling, based in Kiel, has been one of them since 2012. The two founders, mechatronics engineers Jonas and Simon Kühling, specialise in open source hardware development and production in the field of 3D printers. After one and a half years of development, the first product, the "RepRap Industrial", has been in series production since the end of 2013. It is a cost-effective solution for reliable and high-quality rapid prototyping, especially for heavy-duty continuous use
The system is constantly being further developed and has just received a fundamental update and various improvements with version "v1.1.0". All materials that meet certain basic specifications can be processed, ranging from high-strength thermoplastics and fibre-filled plastics to rubber-elastic materials. Printers that are available for domestic use or modelling only allow the use of a very limited range of printing materials. A so-called "bio-plastic" is predominantly used here, which is based on maize and generally cannot withstand the technical requirements of industrial use. This is because this plastic already fails at temperatures above 45 °C - the temperature limits in industry are significantly higher. Compared to other 3D printers for industrial use, the "RepRap Industrial" is particularly recommended due to its price. This is around 25 to 30 per cent lower than comparable systems. The success proves Kühling&Kühling right: the number of units is continuously increasing and has quadrupled within a year.
All materials that meet certain basic specifications can be processed, ranging from high-strength thermoplastics and fibre-filled plastics to rubber-elastic materials.
Simon Kühling remembers the search for a suitable supplier: "When we started developing the system, we initially thought of classic ball bearings. These have several disadvantages. Firstly, they are too expensive at a unit price of around 12 euros, and secondly, they stop working at an operating temperature of 65 °C. At this point, the seals start to fail. Then the seals start to fail and the lubrication wears out." This led to linear plain bearings with plastic sliding surfaces. "For cost reasons, we initially tested Asian products," says Simon Kühling. "However, these in no way fulfil our requirements, not to mention a fast and long-term delivery capability."