This is where Switzerland measures most precisely

Gribi Messtechnik AG has been offering independent and comprehensive services in the field of geometric measurement technology since 2003. The company has two main pillars: 3D metrology on the one hand, and 3D calibrations on the other. Gribi Messtechnik's customers come not only from Switzerland, but from all over the world to have initial sample inspections, single part or large series measurements carried out - if required also in 24-hour operation - as well as the calibration of their test equipment. All branches of industry are represented, starting with the strong Swiss sectors of medical technology and pharmaceuticals, as well as metal processing including precision mechanics, through the automotive industry and its suppliers, to aerospace, mechanical engineering and the watchmaking industry. Gribi Messtechnik also has expertise in gear and worm wheel measurement: gears from module 0.2 are measured.

"We have also made a name for ourselves on the international stage for delivering high-precision measurement results even when market competitors have long since had to wave goodbye," says Managing Director Rudolf Gribi. "If necessary, we also seek new solutions for our customers' metrological challenges." In addition, the family business acts very flexibly: when a customer from Germany called Gribi's mobile phone late on a Friday evening some time ago and made it clear to him that an order was urgent, the company boss made his way back to the measurement laboratory - and received the customer well after midnight.

Accredited according to ISO/IEC 17025

In order to stay ahead as a measurement service provider and accredited calibration laboratory in Switzerland and on the international stage, Gribi Messtechnik continuously invests in technology: As early as 2007, the company built a measurement laboratory in accordance with the VDI/VDE 2627 standard in quality class 1 on the existing premises in the industrial area in Büren. In 2008, it received accreditation according to ISO/IEC 17025 from the Swiss Accreditation Service (SAS). This made Gribi Messtechnik one of the first accredited 3D testing laboratories in Switzerland to meet the strict requirements of the international standard regarding the performance of 3D tests. In 2011, the investment in a high-precision Leitz PMM coordinate measuring machine for calibrations was followed by the accreditation as a calibration laboratory according to ISO/IEC 17025.

But Gribi Messtechnik did not want to be satisfied with this in the long run: "With five tactile measuring devices and a multi-sensor machine as well as two CTs, we were able to meet almost all requirements in industrial metrology in the past," says Gribi. "But at the peak, the requirements in terms of accuracy have once again increased massively in recent years. This applies to high-precision components that we measure, but even more so to the reliable and traceable calibration of test equipment. Therefore, we needed a high-precision coordinate measuring machine."

The existing 3D measuring machines all come from Hexagon Manufacturing Intelligence. "I was and am always very satisfied with the Leitz coordinate measuring machines, especially since the Quindos software opens up all the possibilities for us," says Gribi. "Nevertheless, we openly looked around the market to see which measuring machine represented the absolute optimum. We didn't want to make any compromises in the process. " A comparison of several high-precision coordinate measuring machines showed the company boss that, once again, there was no way around a device from Hexagon Manufacturing Intelligence - the Leitz Infinity. "On paper, the Leitz Infinity didn't initially seem to be the most accurate coordinate measuring machine," Gribi recalls. "Another machine showed better values. But that was pure theory, as it turned out. Our comparison of all parameters relevant to accuracy and verification of accuracy revealed a different picture."

Highest precision for tactile and optical measurements

The closed-frame design of the Leitz Infinity, the high-resolution scales with a resolution of 1 nm and the specified basic accuracy of 0.3 μm - i.e. around 300 times smaller than the thickness of a human hair - form the basis for the superlative coordinate measuring machine. The Leitz Infinity is the most accurate 3D coordinate measuring machine in its class and also enables the combination of optical and tactile sensors in one system. The measuring machine is equipped as standard with the highly accurate tactile high-speed scanning measuring head LSP-S4.

In combination with the non-contact Precitec LR sensor, it is possible to switch automatically between tactile and optical measurement technology within a measurement sequence. Gribi Messtechnik uses the optical sensor, for example, when measuring highly sensitive reference lenses made of glass or plastic that do not allow touching by probes.

In a league with national metrology institutes

With the decision for the Leitz Infinity, Gribi Messtechnik has catapulted itself into a league with national metrology institutes that represent the measure of all things in 3D metrology. In addition, some large corporations as well as major research institutions have a Leitz Infinity. "But among metrology service providers in Switzerland, we are the only ones with this super-precise coordinate measuring machine ", says Gribi proudly.

The Leitz Infinity was delivered and installed at Gribi Messtechnik in 2017. It had a few months to acclimatize in the measuring room. After that, a service technician from Hexagon Manufacturing Intelligence came to the house, who laser-corrected, calibrated and finally accepted the device. "That service technician is still Hexagon's Hexer to me today," Gribi says with a laugh. "He worked in a highly concentrated manner, checked the accuracy status of the machine with step end masses and thereby got the maximum out of the Leitz Infinity. The man had an extreme amount of sensitivity in his fingertips, which was very impressive."

Gribi Messtechnik then tested the Leitz Infinity itself: The first test measurement of a component over seven hours showed that the largest measurement deviation of the coordinate measuring machine at a temperature of 20 °C was just 0.1 μm with a deviation of 0.09 °C over the entire measurement period.

3D calibrations in two accuracy levels

With the Leitz Infinity, Gribi Messtechnik has expanded its 3D calibration offering into the submicrometer range. With three coordinate measuring machines qualified for calibrations - Leitz Reference HP, Leitz PMM and the new Leitz Infinity - the company now offers a wide range of services with two levels of accuracy. "This allows our customers to choose between high-accuracy and standard calibrations at the best cost-benefit ratio for them," says Gribi. "In addition, the Leitz Infinity naturally complements our portfolio of component measurement in the high-accuracy range."

Leitz Infinity enables measurement of tiny screw gauges for implants

At Gribi Messtechnik, the majority of work on the Leitz Infinity currently involves calibrating calibration standards, reference bodies and setting gauges with a volume of 1200 mm × 1000 mm × 600 mm. However, the company has already completed a number of interesting orders with the Leitz Infinity in the field of measurement services as well. For example, tiny screw gauges for implants are currently being measured for a manufacturer in the medical technology sector. "It is only with the Leitz Infinity that we are able to measure these tiny thread profiles at all," explains Gribi. However, this is not possible with standard probes. That's why he and his colleagues have developed a special tactile probe and can thus measure root radii of 0.02 mm without gaps.

Maximum precision is also required in the watch industry: Here Gribi Messtechnik has measured watch plates with the Leitz Infinity. "The industry has always talked about precision in the micrometer range, but today this must also be proven with measurement technology so that the tiny parts can be assembled automatically," says Gribi. "Here, the requirements have increased tremendously."

In the case of mounts for turbine blades used in aviation, the precision of the Leitz Infinity has even contributed to efficiency increases: thanks to the low measurement uncertainty offered by the measuring device, the manufacturer can now use the special grinding wheels used for much longer. The tolerances that he calculated for them in the past can now be fully utilized. This means that the grinding wheels can be used for much longer and the costs for expensive reworking or reconditioning have been reduced. Gribi is pleased: "This is a very good example of how we are also helping our customers to push back the limits with the Leitz Infinity."