Given the intense competition between engineering sub-contractors it is often the businesses with ‘unique selling points’ that stand out from the crowd. For example, while Tyne and Wear-based RDS Precision Engineering has established a reputation for delivering on time and on budget, the company says its main differentiator is its “highly developed quality ethos and regular investments in high-precision inspection equipment”, as highlighted by the Surfcom NEX 041 CNC measuring station from Coventry-based Accretech SBS UK Ltd.

This instrument provides RDS with high-precision two-dimensional contour and surface roughness measurement capabilities.

The company was established in 1991 by brothers Robert and David Bone with the aim of becoming a successful independent supplier of precision-engineered components — an aim they have achieved. Explaining the recent Accretech purchase, Rob Bone, RDS’s engineering director, said: “A policy of regular investments has resulted in our staff now having access to a wide range of first-class inspection equipment. As a BS EN ISO 9001-certified business, quality has always been, and will continue to be, our number one priority.

“We use a selection of standard inspection equipment, such as CMMs and vision-based measuring systems. Also, given the demanding specifications and challenging dimensional tolerances of many of our components, we also use specialised metrology equipment, such as our recently purchased Accretech CNC contour and roughness measuring system. The decision to purchase the Accretech equipment was an easy one.

“Some time ago, a major customer of ours was looking for a CNC measuring station offering high-precision two-dimensional contour measurements and finally selected a Surfcom NEX 041 as being the ideal solution. Given our customer’s in-depth research before their Accretech purchase, and their recommendation, we also invested in a similar unit.”

Suitable for the manual or CNC high-precision measurement of contour geometries, the Surfcom NEX 041 has a contour measuring accuracy of ±(0.8+[2H]/100)µm. Furthermore, the use of kinematic magnetic holders mean the unit’s contour styli can be swapped out ‘effortlessly and with high positioning accuracy’ — and a wide range of contour-measuring styli means that even the most difficult to reach workpiece positions can be inspected.

Straightforward operation
Rob Bone added: “The Surfcom NEX 041’s operation is so straightforward that, following a trouble-free installation and operator training, our staff soon mastered its operation. Now in regular use, our new Accretech machine is proving invaluable. For instance, we were previously using a shadowgraph to measure a regularly manufactured family of parts with exacting angular contour specifications but struggling to achieve the required levels of precision.

Now, we can load each of these parts onto the Surfcom NEX 041, recall the relevant program and instigate an automatic CNC measuring routine. The Accretech machine has not only improved our levels of precision related to these components but also slashed the time taken to inspect them.

“In fact, as our contour inspection routines have been automated, once the operator has loaded each part onto the machine, he can undertake other duties while waiting for inspection cycles to be completed.

“Soon after installing the Surfcom machine we returned to Accretech to buy an additional T-stylus set that allows us to make very accurate contour measurements inside small bores in both downwards and upwards directions. This allows us to measure complex geometries and diameters deep inside bores that were previously very difficult or impossible to measure.”

In conclusion, Accretech added: “As all users’ contour-measuring needs differ, Surfcom NEX machines can be specified with the addition of a wide range of modular accessories and sensors, to ensure the delivery of systems that exactly match the users’ requirements.

“The availability of these accessories and sensors means that Accretech systems remain ‘future-proof’, as they can be modified as users’ inspection needs change. Furthermore, rather than using the ball screw and nut arrangement, Accretech’s products benefit from the use of linear technology that results in significant reductions in mechanical wear and ensures that all products retain their accuracy specification and remain maintenance-free.”