Renishaw CNC Workholding ClampsPosted on February 13, 2017
One of first Matrix pin vices in use in the UK is producing a time and cost saving solution when finish machining prototype and first-off complex free form parts created using the additive manufacturing technique (AM).
The vice was supplied by ETG Workholding to Renishaw’s Digital Manufacturing centre (DMC) based at its HQ site near Wotton-under Edge where self-sufficiency plays a major role with prototyping and component development projects undertaken using Renishaw’s own RenAM 500M additive manufacturing systems. The Centre also doubles as a demonstration facility for Renishaw’s extensive AM manufacturing expertise.
RenAM 500M systems use metal powder bed fusion technology to build complex components straight from the digital CAD files. Many are prototypes for future Renishaw machine and process developments but almost without exception, all feature complex shapes, thin wall sections or have complex geometries. As a consequence, they are difficult to clamp when being finished machined.
Traditionally in these circumstances, a fixture would have to be created involving an initial CAD drawing, prototyping, machining and assembly withinevitable time and cost implications. Now, using Matrix pin vices, Renishaw technicians can create a part specific, stable, secure and repeatable workpiece clamping configuration that can be set up in a matter of minutes.
Renishaw has two versions of clamps from the Matrix Silver X-clamp range – two rail mounted X clamp 40’s for small components and a larger X clamp 125 version which has the capability to offer ‘wrap around’ clamping to create an optimised grip on the work piece. Both are superior to conventional two or three point holding devices where there is also the risk of surface damage at the clamp points.
In Renishaw’s DMC facility the pin vices are fitted to the machine tables on Fanuc RoboDrill D21L 3 axis machining centres which are additionally equipped with 4/5 axis rotary tables to give up to 5 axis capability as required.
Chay Allen, Rapid Manufacturing Manager at the Centre explains how productive the vices have been; “Because the great majority of our machining throughput is literally one off, workholding and fixturing is a potential bottleneck. We saw the Matrix on ETG’s stand at MACH 2016, took a few examples of free form parts to their Hyfore facility for real-time machining tests and decided this was the way forward. They have saved many production hours due to their versatility and we have been impressed with how they hold their accuracy on repeatable machining operations.”
Renishaw employs its own probing systems to inspect the finish machined parts but also uses ‘NC-Perfect Part’ digital monitoring software from its associate company MSP for checking surfaces, contours and alignment machining. All workpieces are heat treated prior to machining.
“The smaller vices enable is to secure complex components across the two while the large version accommodates bigger shapes, however complex,” adds Chay Allen. “We are not using the clamping capacity to its full capability but the security of grip, given the complexity of the workpieces, coupled with the significant time savings have enabled us to considerably streamline component throughput.”
ETG Workholding experts have first-hand experience of a wide range of clamping and fixturing techniques and can be contacted to discuss specific requirements or undertake demonstrations.
Issued on behalf of the Engineering Technology Group, Wellesbourne Distribution Park, Loxley Road, Wellesbourne, CV35 9JY.