Swiss Watchmaker Integrates Toolholding System to Maintain High Precision |
|
|
Armin Strom began to build a legacy when he hand-created his first skeletonized watch in 1983. Over the years, the watchmaker's reputation grew, and he eventually founded Armin Strom AG to carry on his tradition of excellence. The company produces extremely small lot sizes of prestigious products that sell for as much as $80,000 per watch. Recently, Armin Strom AG partnered with REGO-FIX to integrate the powRgrip toolholding system into its operations. Watches consist of many tiny components, all of which require incredible precision to ensure the intricate movements necessary for flawless operation. Throughout production, conditions must be optimized to ensure that gears and other parts emerge with the tolerances required to function smoothly. Even the smallest component driving a watch's movement must perfectly fit within the system as a whole. Successfully manufacturing world class watches requires dexterity, devotion and accuracy. Tooling plays a vital role in achieving an environment that makes this possible. As Armin Strom AG established a completely new factory for production of its "Armin by Armin Strom" line of watches, the company dedicated substantial resources to ensuring it only invested in the equipment best suited to its demands. This represented a significant departure for the company, which had previously focused exclusively on hand-skeletonized watches. Located in Biel, the facility was to maintain Armin Strom's uncompromised standards by incorporating the latest innovations in high performance machines, precision tools and high quality toolholding. As Workshop Supervisor of Armin Strom AG, Michael DŸenner bore the responsibility of selecting equipment and setting up processes at the new facility. To prepare for this task, he visited numerous trade shows to view and evaluate potential solutions for the new production system. It was of the utmost importance that the operations be optimized before manufacturing even began. In reviewing the company's options, Mr. DŸenner felt it was especially important to have a toolholding system that would maximize the performance of both tooling and machine. "In my previous work, I was familiar with heat-shrink chucks and their advantages and drawbacks," said DŸenner. "I had also had some exposure to REGO-FIX as a manufacturer of precision tools and had positive experiences with its ER system. My attention was drawn to the powRgrip technology at the 2008 Siams trade show in Moutier, Switzerland." Several aspects of the powRgrip system piqued the interest of Armin Strom AG. The system promised high precision, effective vibration dampening and excellent balancing. It also appeared to be very easy to operate, with low operating costs and a long product life. Armin Strom AG also appreciated that the system was environmentally friendly, as it required no recurring water or electricity costs. Convinced of powRgrip's potential, the company invested in the PG10 and PG15 systems to be used with a variety of Mikron machining centers. The combination of powRgrip systems offered flexibility, allowing for the use of tools with shank diameters as small as 0.2 mm for high precision machining of plates and inner parts. Because of the nature of parts being produced, Armin Strom AG did not need to take advantage of the powRgrip system's capability for high material removal rates and holding forces. Instead, the focus was on achieving minimum run-out with optimal vibration dampening. "Our internal concentricity measurements with the powRgrip system show average values of 2 µm with a fixed tool," said DŸenner. "The Mikron machining centers contain a sensor which indicates if the tolerance of concentricity is exceeded. With the powRgrip system, we find the sensor is always in the green zone." The powRgrip's vibration dampening is made possible through the functional contact surfaces between the tool and collet, as well as between the collet and toolholder. The powRgrip system uses a mini press with six tons of force to join tool to toolholder, achieving clamping forces through the mechanical interference between holder and collet. As no clamping mechanism is required within the toolholder itself, the system is able to offer much higher rigidity. The full wall thickness of a powRgrip holder is available to absorb radial forces, reducing vibration. The nature of the system also prevents the deformations due to heat and vibration that can occur with a heat-shrink chuck. "When we were looking at our options, we talked with other watch companies that had been using powRgrip for a long time and who worked with the system on a daily basis," says Mr. DŸenner. "They all provided a very positive response, which was a large factor in our decision to use the system. Having achieved the results ourselves, it was definitely the right choice."
For more information
|
 Armin Strom AG uses the powRgrip system to hold tools with shank diameters as small as 0.2 mm.
Responsible for the quality of Armin Strom AG's processes, workshop supervisor Michael DŸenner evaluated multiple toolholding technologies before selecting the powRgrip system.
The watch components manufactured at Armin Strom AG require incredibly high levels of precision, the company said.
Blurring the line between manufacturing and art, watches produced by Armin Strom AG sell for as much as $80,000.
|
