Pfisterer Feinwerktechnik was founded 18 years ago in Bernau am Chiemsee. The medium-sized company produces high-precision small and micro parts in two shifts for sectors such as medical and laboratory technology, as well as for the semiconductor industry and special machine construction. "Our customers are small, medium-sized and large companies from the region, for whom we manufacture products and whose locations worldwide. But we also have customers from Switzerland, Austria, China, Malaysia, England and the USA," explains company founder and Managing Director Georg Pfisterer. "The quality standards are often very high, many of our customers are certified and require test reports and protocols for documentation. We have to meet these requirements. That's why we have an employee who is exclusively responsible for quality assurance," continues Pfisterer.

From pinhead to shoebox

The company's quality standards are always high. This is also important, as the size of the components alone suggests that machining is not easy. Some of the work is very small and delicate. "On average, the milled parts are about the size of a matchbox, with the smallest parts being the size of a pinhead and the largest components the size of a shoebox," says Pfisterer, describing the workpieces. This is one of the challenges.

Pfisterer uses the Acura65 to produce plastic housing covers for laboratory equipment. Only aluminum is machined more frequently. (Image: Hedelius)

In addition, the workpieces must be machined with high precision. It is often a matter of hundredths. For example, milling fits with an accuracy of six micrometers is not uncommon. These machining operations are carried out on an Acura 65 from Hedelius in Meppen, among others. The five-axis milling machine with rotary swivel table from the North German manufacturer was put into operation in 2017. "If precision is required, we mill even the smallest parts on the Acura," says Georg Pfisterer. Aluminum and plastics are often machined, but stainless steel and titanium are also milled with the compact machine. As a lot of aluminum and plastic is machined, the five-axis machine was equipped with an HSK A63 spindle and 18,000 ^rpm. Another reason for the high speed is the very small tools that are frequently used.

The machining center is used to machine the contract manufacturer's entire range of parts. However, the milling machine is most frequently used for recurring parts and medium-sized series.

Adherence to deadlines is crucial

The Managing Director explains: "Our customers order batch sizes of between one and 500, sometimes weekly, monthly or quarterly recurring parts, sometimes just a single part. We have to be able to react to this. Adherence to deadlines and same-day delivery are crucial for us." The Acura 65 was therefore also equipped with a zero-point clamping system and a standby tool magazine with a taper cleaning station. In addition to the 65-position standard magazine, which can be operated from the front during machining, a further 180 tool positions are available. "With the standby magazine and the zero-point clamping system, we can significantly reduce set-up times for recurring parts. Vices are prepared and tools are immediately available," says Georg Pfisterer enthusiastically about the system.

For laboratory equipment, Pfisterer mills the cassettes for the entire optics on the Acura 65. (Image: Hedelius)

With travels of 700 x 650 x 600 millimetres on a footprint of 2,725 x 2,850 millimetres, the Acura 65 offers large machining options in a very small space. This compactness was important for the precision engineers from Bernau, as space is at a premium in the production hall. Twelve CNC turning and milling machines are already in use, and a further turning/milling center will be delivered shortly.

Despite its compact design, the machine has a large sliding door and large viewing window. When the door is open, the machine operator can get very close to the machine table. In order to keep operation as simple as possible for the employees, a Heidenhain TNC 640 was chosen for the control system. "Our employees are familiar with Heidenhain, we also have the controls on other machines. We wanted to avoid a mix of different control systems," says Georg Pfisterer, explaining the decision. Pfisterer's employees often program components on the machine, while more complex parts are programmed using a CAD program. as