Using CNC milling to create customised assembly tools was an extremely labour-intensive operation and did not easily allow for adaptation or improvement. Tool manufacturing cost was high and produced a lot of waste, which slowed down the assembly line. As a solution, Märklin installed 3D printers, which allows the company to produce tools, jigs and fixtures in a short timeframe. The result is that 3D printing has almost entirely replaced the traditional methods of assembly tool production in certain areas. “We realised the benefits of 3D printing very quickly, especially the production flexibility, which has accelerated delivery times of parts,” said Michael Zauner, Märklin Project Supervisor and Innovations Management.
“3D printing allows us to produce a customised tool within a day, compared to several weeks, meaning employees can focus more on producing the model trains instead of manufacturing tools. This is also aided by the increased design freedom that 3D printing offers. For low- to medium-volume production, the improved efficiencies and distribution of labour within the company have taken our production to another level and ensures our business runs effectively.”
Creating model trains is a multi-stage production process. The need for flexibility and easy-to-use tools is essential. One example is the production of the clamps used in digital printing. In this process, the model train casing is printed (labeled) with the required design to achieve the utmost authenticity. When using traditional CNC milled steel clamps, the quality of the printed parts is compromised because the applied high pressure puts a strain on the models. In contrast, the durable but light 3D printed clamps hold the train components in place without incurring damage. Märklin has partly replaced steel clamps in the manufacturing processes, or combined CNC-milled parts together with 3D printed components in the same tool to achieve optimum results. To support its 3D printing capability, Märklin uses Stratasys FDM and PolyJet technology.
“Rethinking how we construct tools has
been a focal point for our production line and
design team,” Zauner explained. “Besides the
FDM technology, we have also discovered
PolyJet technology for manufacturing our jigs
and fixtures. Being able to combine soft and
hard materials in one print provides us with
manufacturing tooling options we didn’t
have previously.”
3D printed designs are stored digitally and can
be easily reproduced or adapted, giving the
company more flexibility to quickly adjust and
tailor tools to train models or processes. 3D
printing has enabled the team to include tool
and purpose labels on the CAD designs without
additional costs, so the printed parts are clearly
marked and allocated to the correct step during
their manufacture. This avoids the need to
halt production, resulting in an improvement in
production workflow.
“Our employees now ask what else they can 3D
print,” Zauner said. “They have recognised the
advantages in their own work as well as more
widely throughout manufacturing. Indeed, the
way in which it makes production more efficient,
while also allowing time for employees to come
up with new ideas, has seen 3D printing truly
open up lots of opportunities for us.”
