Two machine solution for F1 carbon fibre

To cope with the different demands of machining composite materials as opposed to metals both machines, prior to delivery to Renault’s F1 team, were significantly modified and supplied with integrated, high-efficiency extraction systems as well as fully-enclosed and sealed working areas.

The machine modifications were implemented as part and parcel of a longstanding technical partnership agreement between the two companies.

In 2017, GF Machining Solutions, the EDM, 3- and 5-axis machining centre and laser machine tool and automation solutions specialist, supplied the Renault F1 team with two new high-performance 5-axis machining centres.

The two new Mikron HPM 1350U machines were installed at Renault F1 Team’s manufacturing facility in Enstone, Oxfordshire in the team’s expanding composites department.

Both machines were acquired, initially, to machine high-precision patterns made from epoxy resin tooling board used to make moulds for carbon fibre reinforced plastic (CFRP) body parts.

However, owing to the machines’ versatility and performance attributes, the HPM 1350Us are also being used to machine carbon inserts, and Rohacell foam, used as a structural filler to strengthen carbon fibre composite parts, as well as a range of jigs and fixtures.

Accuracy advantages

The decision to invest in the two new Mikron HPM 1350U machines was made as a direct result of accuracy issues being experienced in Renault F1 Team’s composites department, and the inability of existing equipment to meet increasingly stringent part accuracy requirements.

Renault F1’s composites manager, Keith Dunsby explains: “We are committed to continuous improvement and are always striving for excellence, so when it became apparent to us in 2016 that two of our machines were not able to meet the accuracy and repeatability requirements demanded by our design engineers, we acted quickly to rectify the situation.

“Since being installed in April 2017 the machines have been working around the clock, during the day, throughout the night and at weekends, and they haven’t missed a beat. From struggling to hit 0.5mm positional accuracies previously we are now achieving 0.1mm accuracies or better on the HPM 1350U machines.”

The working envelope of the HPM 1350U machines (1,350mm x 1,150mm x 700mm) enables Renault F1 to machine the majority (up to 60%) of these parts. For larger components like the car chassis itself, or a rear crash structure, the team relies on big gantry-type machines with a 4m x 3m working area.

Productive partnership

Renault F1 has a long-established technical partnership agreement with GF Machining Solutions which has been instrumental in Renault investing, over recent years, in a number of AgieCharmilles wire and die-sink EDM machines and Mikron high-performance 5-axis machining centres.

To address the accuracy issues being experienced in the composites department it was natural that Renault approached GF Machining Solutions first.

Richard Ferguson, the Renault F1 Team’s composites supervisor comments: “This was, to all intents and purposes, a different requirement in that previously, the Mikron machines acquired for the machine shop were for machining metal components.

“We explained the issues and our requirements to GF and they recommended the HPM 1350U machines for their size, power, versatility and performance, but with a number of significant modifications to make them more suitable for machining composite parts.”

These modifications included the integration of a high-efficiency extraction systems installed on the machines’ tables.

Mr Ferguson continues: “Machining carbon fibre composites and Rohacell foam essentially creates a significant amount of dust which needs to be removed quickly and safely from the interior of the machine and the wider machining area and environment. Positioning the extraction units on the machines’ tables delivered an effective and optimal solution.”

The modifications to the HPM 1350U machines also included the removal of swarf conveyors, enclosing the machine’s Y-axes and providing additional guarding to prevent dust ingress and escape.

A final modification on both machines was the inclusion and integration of the more advanced Renishaw RMP600: a compact, high-accuracy workpiece probing system featuring radio signal transmission which, working in conjunction with the team’s MSP software, ensures improved process reliability, faster and more accurate set-ups and reduced scrap.

“The customisation of the HPM 1350 machines demonstrates the power of the positive partnership we have with GF and the way in which specific needs can be quickly addressed and solved through collaboration and by thinking outside the box,” Mr Dunsby affirms.

Positive results

The HPM 1350U machines’ arrival in April 2017 enabled the composites department to improve its own productivity, and have a direct and positive impact on the Renault F1 team’s performance in the 2018 season. Renault finished fourth in the 2018 season’s Constructors’ Championship; two places higher than in 2017.

“The HPM 1350U machines are reliable high-performance machines,” Mr Dunsby notes. “They are equipped with high-torque spindles that enable us to ramp up feed rates and achieve large depths of cut which, as a result, have helped us improve our productivity levels, reduce part cycle times and meet tight lead-times.

He concludes: “The 5-axis configuration of the machines also has a positive impact on productivity (and accuracy) as complex and intricate parts can be machined in fewer set-ups using 3+2 and full simultaneous 5-axis machining operations.

“Although initially acquired to machine bodywork patterns, the machines’ versatility and all-round performance has meant that they are being used to machine a wide range and variety of parts, which has clearly resulted in a better ROI than was originally imagined.”

GF Machining Solutions www.gfms.com/uk