Frequently asked

In most measuring rooms the CMM software is pre-configured once by the OEM service technician, and from then on norm conformity is assumed rather than verified. That is a real risk: the evaluation method behind a result (for example a Gaussian best-fit instead of the ISO two-point size per ISO 14405-1) can quietly diverge from the standard your drawing references. An independent conformity check compares what your software computes against what DIN EN ISO 1101, ISO 14405 and ISO 14253-1 actually require, so you can prove conformity instead of presuming it.

ISO GPS (Geometrical Product Specification) is the standard system used across the DACH region and the wider EU, with DIN EN ISO 1101 governing geometrical tolerancing. ASME Y14.5 is the North American equivalent. The two agree on the surface but diverge in roughly two thirds of practical cases: the same symbol can be defined differently, asymmetric tolerance zones use different notation (ISO UZ versus ASME U), and ASME Y14.5-2018 removed concentricity and symmetry entirely while ISO retains coaxiality. Reading a drawing under the wrong standard is one of the most common sources of wrong inspection results.

Not always. Some evaluation software cannot compute certain characteristics the way the ISO standards prescribe, for example the two-point size of parallel surfaces per ISO 14405-1, and instead falls back to a default association method. Coverage differs by product and version. The practical question is not which CMM brand you own but whether, for each characteristic on your drawing, the software is set to the ISO-conformant evaluation. That is exactly what a vendor-neutral review establishes.

A frequent cause is applying the ASME Y14.5 method to an asymmetric tolerance zone that is specified under ISO, which yields different numerical limits and therefore wrong values in the Erstmusterprüfbericht (EMPB) / First Article Inspection Report (FAIR). When the customer re-measures under the ISO method, the numbers do not match and the report is rejected. Correcting the evaluation method at the program level removes the discrepancy at its source.

ISO GPS is organised by the ISO-GPS matrix model (ISO 14638), which links every standard from the drawing indication through to the measurement result. The core set includes ISO 8015 (fundamental principles), ISO 14253-1 (decision rules), ISO 14405 (dimensional tolerancing), ISO 1101 (form, orientation, location and run-out), ISO 5459 (datums), ISO 21920 (surface texture) and ISO 22081 (general tolerances). Treating these as one connected system, rather than isolated symbols, is what makes a measuring program defensible in an audit.

Measurement System Analysis (Messsystemanalyse) is the set of statistical studies that establish whether your measurement process is good enough for the tolerances you have to verify. It covers gauge capability, repeatability and reproducibility (Gage R&R), and in the automotive supply chain the VDA 5 procedure for test process suitability. You need it whenever a measurement is used to accept or reject parts and you cannot otherwise prove the measurement variation is small relative to the part tolerance.

Both. Program reviews, drawing and standard interpretation, documentation audits and training are often handled remotely. On-site visits are used for hands-on CMM work, process observation and measurement system studies. The geographic focus is Switzerland, Germany and Austria, with support across the wider EU and for export-facing work toward the US and China. Working languages are German and English.