The two CNC coordinate measuring machines (CMMs) Alltrista Plastics had been using 24/7 for more than 10 years at its Christchurch, UK factory had become inefficient. The accuracy and repeatability of touch-trigger probing were becoming compromised due to the age of the machines. The software would sometimes crash, risking a physical collision, damage to the probe and perhaps even to the component being checked. As the plastic medical parts and assemblies produced had become more complex over time, an angled stylus was often required in an inspection cycle, so an operator had to choose from half a dozen pre-set probe configurations, mount one manually and calibrate it. Additionally, the person would have to sort through different programs on a computer screen to identify and load the correct one.
This whole process has been streamlined and automated with the installation of two new Altera S 10.7.6 CMMs manufactured by LK Metrology in Castle Donington, UK. The supplier’s CAMIO 3-axis scanning and reporting software was also provided along with a Renishaw SP25M scanning probe and PH10M motorised indexing head. It is in effect two sensors in one, enabling continuous path tactile scanning as well as touch-trigger probing of discrete points. Together with a Renishaw matrix plate to allow accurate placement of parts for inspection, the set-up has resulted in a vast improvement in metrology productivity by facilitating fixturing of samples, speeding measuring cycles and virtually eliminating human intervention and the attendant risk of errors. It would not have been feasible to retrofit scanning capability to the older CMMs, as the cost would have been prohibitive and in any case the machines were becoming obsolete.
Alltrista’s quality manager Peter Makosa said, “I operated LK CMMs for several years when working for an aerospace manufacturer, which had standardised on their use.
