Swepac International AB uses a 3D printer to print prototypes and pre-production series, allowing them to move seamlessly from prototypes to production.
Swepac International AB, based in the southern Swedish town Ljungby, specialize in the field of equipment for soil compaction and concrete treatment, sturdy solutions that need to withstand a tough work environment. This year, the company will start rolling out a new generation of solutions, with new and smart functions. One of the biggest upgrades is that all equipment will have a cloud connection, where the user can access services. Every model will also feature an RFID based ignition key.
”All electric-powered equipment will feature this new system, with RFID, touchscreen panel and cloud connection”, says Tomas Johansson, construction engineer at Swepac. “With our new generation of solutions, the ignition will be RFID based, which is a safer and more robust system.”
Anyone working with manufacturing knows that the step from product development to serial production can be challenging. Ordering tools for tens of thousands of euros, when all you have as a reference is a 3d file, can send shivers down any engineer’s spine. This was also the case for Swepac, when planning the production of the components for the RFID based key. The risky step going from development to production can be mitigated by creating physical prototypes.
Another challenge for Swepac was the need for physical prototypes to show at trade shows, some of these were quite time-critical. Lastly, the company also needed to produce a pre-production series of their new RFID based ignition key, to be tested by some of their customers. Here, the challenge was to create the look and feel of the end use product, while retaining the mechanical properties needed.
Swepac chose to 3D print both prototypes and their pre-production series. With previous 3D printing experience, Tomas Johansson used a local service bureau, TA Engineering. The company was founded by Tibor Albert, who, fortunately, have previously worked with Tomas at Swepac.
The components that needed to be 3D printed were a top and bottom part to house the RFID tag, and a case for the keyhole.
In the design phase, Tomas made sure all 3d models were exported from SOLIDWORKS directly to TA Engineering. The files were then converted to the 3D print file format stl, the standard file format regardless of what printer type you use. The stl file allows for the model to be sliced in to many thin layers.
At TA Engineering, a minor change was made to the build angle, that is, the angle at which the component is printed. Adhesion is often lower in the Z axis, and by tweaking the build angle, you affect the mechanical properties. But in Swepac’s case, by changing the build angle, the 3D printed part got a smoother surface finish.
All parts were printed on a 3D Systems ProJet MJP 2500. The technology is Multi Jet Printing, which inkjets material droplets in thin layers on to a build plate.
Swepac also wanted to use self-tapping screws to assemble the RFID key casing. TA Engineering therefore chose the material Visijet ProFlex M2G DUR Transparent, developed for the 3D Systems printer ProJet MJP 2500. The material fit the bill perfectly.
”Another challenge in finding a fitting material, was the need for colouring the part”, says Tibor Albert, CEO, TA Engineering. “The final part has a black top and a red bottom part. We first used ABS, but the end part was too brittle for the self-tapping screws. The Visijet material we chose is both strong and a bit flexible, which suited our needs.”
Every set of parts take about four hours to print. They are then painted, dried and assembled.
”The production workflow has been hassle-free”, says Tomas Johansson. “All we need to do is to upload SOLIDWORKS files to TA Engineering, for next-day delivery.”
”Time is always of essence for the company, and we use 3D printing to cross the finish line faster.”, says Tomas Johansson. “3D printing also enables us to make design and functionality changes in the prototoyping phase, something not possible in a pure digital environment. It’s much easier making decisions with a physical model in your hand – the technology really allows us move smoothly from idea to tool.”
Swepac are so pleased with the results, that they will use 3D printing to manufacture a pre-production series of RFID keys, to be tested by select customers.
”We will definitely use more 3D printing in the future. It is a great advantage when we need to produce prototypes or test performance.”