Prototyping Labelling Machine through 3D Printing and Reverse Engineering

Design engineering company ReitlingerEngineering GmbH+Co. KG, Weinstadt-Endersbach, used reverse engineering and 3D printing to develop a labelling machine. This produced a flexible, fast and inexpensive solution compared to alternative methods.

 In order for the labels to be stuck on correctly, a constant alignment of the labeled product in the station has to be ensured. This is done with two aligning jaws which fit flush around the product from both sides. The 3D CAD models required for this are often difficult to obtain from the product manufacturer. “However, the precise geometry is absolutely vital and remodeling is very costly and time consuming,” designer Matthias Körner explains.

Nevertheless, this was often the only way: Measurements had to be taken by hand and then transferred manually to the CAD system. The resulting plastic plates which matched the product geometry on these planes were then CNC machined from smooth plastic material and fitted in a universal holder made from aluminum. This was an expensive procedure. ReitlingerEngineering therefore looked for a faster and more economical solution. The result was the use of reverse engineering with a 3D scanner and the subsequent printing of the three-dimensional object with an X350 3D printer from German RepRap.

Instead of modeling the form of the labeled product by hand, the engineering company simply scans the originals with a David SLS-2 3D scanner. The collected data is then converted to a CAD model and used as the basis for the design of the aligning jaws. This prototype is then printed later on the X350 3D printer.

The X350 3D printer from German RepRap features a rectangular build platform and a 350 x 200 x 210 mm build envelope. A minimum layer thickness of 0.02 mm is achieved. With a positioning accuracy of +/- 0.1 mm combined with a stable metal design developed for industrial use, it enables the continuous production of precise and dimensionally stable print models. “Depending on the product geometry, this procedure reduces the time required by between 25% and 40%,” Körner acknowledges.

“3D printing gives the designer extensive design freedom. We looked for a shape that would take into account the flux of forces in the part,” Matthias Körner recounts his experience.
The new design eliminates the need for the aluminum support structure previously required for plastic plates, and combines it with the aligning jaws touching the product into a single part, which is approximately 70% lighter as a result. This has benefits in the machine with fast production cycles. Furthermore, the dimensionally accurate holding of the original eliminates the need for adjusting screws in the aligning jaw design. Aligning jaws are available with different colors for different products that are labeled in the same machine.

ReitlingerEngineering was thus able to give the customer a set of these aligning jaws within a few days. Körner sums up: “This procedure ultimately provided a complete solution from problem definition right through to the finished part, which reduces costs and material and at the same time provides new design possibilities for the customer.”