Anyone visiting Pitmatec Zerspanung in Ellwangen enters a large new production hall equipped with state-of-the-art machinery for the multi-axis complete machining of components. The young family business has defined its niche in the market: The team distinguishes itself as a manufacturer for complex machining projects from batch size 1 through to series production. Without the close cooperation with technology partners such as the machining expert Walter, projects such as the future finishing of a free-form Wiko housing would hardly be economically feasible.

Detlef Pitan, founder and Managing Director of Pitmatec, says: "We gave a lot of thought to how we wanted to position ourselves on the market as a newcomer. We quickly realized that we didn't want to start out as a garage company, like many start-ups in the machining industry. We decided to set up our processes as Industry 4.0 right from the start, digitally based and, above all, fully networked. As a contract manufacturer, we can plan and set up new machining processes extremely quickly, especially for complex components or machining steps. The advantages are short distances, the latest technologies and a team of digital natives who also do all the programming themselves - that's what makes us special." Pitmatec has therefore invested heavily in technical equipment: There is a DMG Mori CTX beta 1250 TC and a Hermle C42 U Dynamik in the hall. The finished components or intermediate steps can be checked directly on a Zeiss portal measuring machine.

Cooperation at eye level

Detlef Pitan and his son David have defined clear criteria for the selection of technology partners. Without agile and reliable partners in an area as strategically central as cutting tools, the company's aspirations can hardly be realized. Detlef Pitan explains: "The most important thing for us is quick accessibility and partnership at eye level. We don't want to be the last in the food chain because we are small. We are quite far ahead technologically, so we need a partner who gives us access to their latest technologies and innovations. It is essential for us to be supported quickly by technically competent and experienced sales staff. After a few conversations with Walter, we had the certain feeling that they understood where we wanted to go. An assessment that proved to be true during our collaboration."

The Ellwangen-based start-up is supported by Walter through Josef Spaag. The technical consultant outlines the scope of the collaboration: "Being involved in the planning and implementation of machining processes right from the start is an ideal situation for both the customer and Walter. Pitmatec is not afraid of innovations or unusual approaches to a challenge. When using new tools, we learn together, as is the case with the current project with the new Walter circular segment milling cutter. Before we started working on specific projects, we first had to equip Pitmatec with a range of cutting tools and holders to enable the most universal use possible. In addition, a tool dispensing system with the corresponding management software was installed to ensure the most seamless tool supply possible. Modern machining is about more than just turning, milling, drilling and threading. It's about achieving goals faster, safer and more precisely - with solutions that make projects more effective and efficient."

Implement surface treatment economically

The close cooperation between the machining professionals at Pitmatec and Walter was essential for the implementation of the challenging "Future Finishing Wiko Housing" project. David Pitan, master machinist and production manager at Pitmatec, explains: "Pitmatec also comes into play when a manufacturer's previous supplier is unable to meet increased quality requirements or tighter time frames, or when a workpiece has a more complex geometry. The Wiko housing is such a case. We involved Walter in the planning process at a very early stage. Together, we developed a process that achieves the desired result with economically viable parameters."

The challenge that the component poses for machining is not immediately apparent: The basic geometry is easy to reproduce, but the difficulties lie quite literally on the surface. It is 3D free-formed, and a high surface quality is also required. This in itself is technically demanding and complex. The change in material further increased the complexity of the project. In another version, the housing is made from EN AW-7075, whereas in the current project it is made from 16MnCr5. In order to achieve the appropriate surface quality for the flank face shape, a conventional radius copy milling cutter with line jumps of 0.1 mm would have to be used. However, this is not economically feasible, but only with the latest technical means - and a machining strategy that makes optimum use of them.

High process reliability with reduced processing time

Pitmatec manufactures the Wiko housings on the five-axis Hermle machining center. The machining center not only provides the necessary mobility in space, but also the necessary dynamics to be able to manufacture the workpiece with just a few reclamping operations. The possibilities of the machine in 5-axis simultaneous machining can only really be exploited with the appropriate cutting tool. David Pitan therefore sees the decisive factor for the success of the project in the opportunity to be able to access machining technologies at Walter that are still in the field test stage. The original idea was to use a radius copy milling cutter, but Josef Spaag from Walter came up with a new Walter MD838 Supreme circular segment milling cutter in the conical version as a solution. This had already shown in the Walter Technology Center and in field tests that surfaces can be finished up to 90% faster than with the previously used method.

The circular segment geometry and the coating enable milling with dynamic contact points and therefore a significantly higher feed rate. It is 0.17 mm per tooth. The cutting speed is 600 m/min. Milling takes place in line increments of 2 and 3 mm. The total feed rate is a good 8,000 mm/min. The new milling cutter is not only particularly fast: the coating and geometry enable extremely high conformity to the specifications of the component even during finishing. This reduces the effort required for polishing. For Pitmatec, process reliability and cost-effectiveness are the decisive factors: With the future finishing strategy, Pitmatec achieves a processing time per workpiece that makes the job economical in the first place. The circular segment milling cutters are available from Walter as standard tools.

Walter Tools, http://www.walter-tools.com PitMaTec, http://www.pitmatec.de