Milling thermoplastics with a low machining temperature

Thermoplastics are plastics that return to their original shape after heating and cooling. Due to the many advantages, thermoplastics are among the most successful plastics. They are used in everyday products in automotive engineering or in medical technology as well as in highly specialized areas such as food technology and the packaging industry. Thermoplastics have become indispensable, especially in resource-efficient lightweight construction.

It is crucial to keep the machining temperature as low as possible when machining these materials. Otherwise the material becomes soft and elastic, is no longer dimensionally stable and can then no longer be processed smoothly and without burrs. The thermoplastic material practically avoids the cutting edge and the tool then scrapes past the edge of the workpiece with the free surface, heats up the material further and it starts to smear. The consequences are burrs, smeared tools and workpiece cutting edges, which then have to be removed manually at great expense. In addition, the correct programming of the CNC paths also plays an important role in machining without rework. Our application technology team will be happy to advise and support you.

The group of thermoplastics includes polyolefins such as PE, PP and PVC, styrenes such as PS, SAN, ABS and POM, fluorine-based thermoplastics such as PTFE, FEP and PVDF, polyamides PA, polyester thermoplastics such as PET, PPE and PEEK, the Polysulfones, polycondensates PSU, PES, PPS, PI, PAI and PEI as well as all other thermoplastics.

High feed rates and clean cut edges without burrs

With tools from the Universal Line and the Sharp Line Hufschmied optimal conditions for machining thermoplastics. Depending on the requirement profile and the machine park, one, two or three-edged tools can be used. Depending on the requirements, one should also choose between torus, end mills and full radius milling cutters Hufschmied to get voted. In any case, the existing machine technology also plays an important role. Basically, the higher the available spindle speed, the fewer cutting edges should be used.

In the case of thermoplastics, it is mainly the freedom from burrs and the quality of the cut edge that are important at high feed rates. The Hufschmied Tools of the Universal-Line and Sharp-Line are optimized for these objectives and promise a post-processing-free quality. That is why most of the tools are also available with different directions of twist, right-hand twist or pulling, left-hand twist or pushing and straight.

In the case of vacuum-clamped components, we recommend the use of pushing tools, i.e. left-hand twisted tools, for most machining tasks, since the cutting force works in the direction of the clamping force of the vacuum clamping device due to the pushing design. The part is also pressed even more firmly into the clamping device, it lies much more quietly and vibration-free and the cut edges are much smoother and cleaner. However, care must be taken to ensure that the chips that are produced during machining are not compressed in the device, but can escape freely.