3D printed molds for prototyping acoustic engine covers with Filaticum Glass Reinforced

Cadminton Hungary Ltd. models, designs and 3D prints engine covers, soundproofing elements and heat shields for car manufacturers and automotive suppliers.

Their work includes designing and production of molds for prototyping acoustic engine covers. Previously, they aluminium molds were used for this task, which was an expensive way to produce small number of prototypes. The 3D printing proved to be a cost-effective solution for making these molds.

Currently, 10 to 15 such molds are produced each year at the company’s site in Dunakeszi.

The acoustic engine cover is made of polyurethane foam. The foaming material is placed into a 3D printed mold, which fills the available place, while the mold must withstand increased pressure and temperature. In order to speed up the chemical reaction that causes foaming, the empty mold is preheated to about 60-70 ⁰C. For a standard PLA filament, even this temperature can be challenging. Then, when the polyurethane is filled into the preheated mold, the chemical reaction of foaming generates additional heat and the inside of the mold can heat up to 80-90⁰C. Normal PLA filament cannot withstand this temperature without softening.

Cadminton’s experts were looking for a filament that could be printed as easily and precisely as PLA, while at the same time withstands temperatures of 80-90 ⁰C generated during the foaming process.

After testing several filaments, they chose Filaticum Glass Reinforced. This PLA-based filament is easy to print, while its heat resistance is up to the task.

The 3D printings also confirmed that objects printed from Glass Reinforced filament are mechanically very stable, making the mold suitable for the integration of metal parts. If the mold needs to be fixed to something, the threaded inserts of the metal fasteners and pins required for this can be integrated into the mold.

The molds 3D printed with Filaticum Glass Reinforced filament with high heat resistance provide a reliable, high-quality solution for the acoustic engine cover manufacturing.

“By introducing 3D printed molds, our customers can save significant development costs and time. Previously, there were produced 5-10 metal molds for each design phase, out of block, at high cost and depending on size it took around 8-12 weeks to prepare. With 3D printed tool, this time is reduced to a few days and material usage is minimised. All this requires a filament with a high heat resistance and good printability. This way we can make molds for polyurethane foam almost in series production.” István Kovács, Development Engineer, Cadminton Hungary Kft.