Headquartered in Fontwell, West Sussex and operating from four sites near the south coast of England, GTR Composites is known for supplying Formula One teams with carbon-fibre components and assemblies. The subcontractor has produced lightweight chassis and other large parts from composite materials for a long time, but at the beginning of 2021 it started final-machining them to tolerances measured in tens of microns.

The introduction of this new service followed the purchase of a German-built Zimmermann FZU400 five-axis machining centre, installed at GTR’s Bognor Regis facility at the end of 2020 by UK sales and service agent Kingsbury. Having a 4000 x 3000 x 1250 mm working envelope, the portal machine was selected from a shortlist of three due to its ability to hold very high accuracy.

For example, a positional tolerance of 50 µm is achieved on features across a full chassis, while holes and counterbores are held to within 10 or 20 µm. As the components are of high value, GTR adopts a policy of having an operator permanently in attendance, even when the FZU400 is running overnight.

Simon Kingdon-Butcher, joint owner (with John Biddlecombe) of GTR, says: “The Zimmermann machine stood out in terms of its rigidity, which translates into the tight tolerances we are able to hold when cutting carbon fibre. We’re able to impress our customers by hitting really tight limits that our competitors cannot achieve.

“High spindle power – 34 kW continuous/41 kW peak – enables us to rough aluminium moulds, while spindle speeds up to 24,000 rpm means their surfaces can be finish-machined to very high quality using minimum quantity lubrication,” he adds. “MQL also enables us to mill and drill carbon fibre components containing titanium or aluminium inserts in the presence of a specific type of coolant approved by our customers.”

For further information
www.kingsburyuk.com

NSK’s ground ball screws, linear roller guides and super-precision ball bearings are helping IMSA to consolidate its market position in the field of specialised deep-hole drilling machines, which are particularly popular for mould-making applications in the automotive sector.

“Our partners have always played a fundamental role in all of the technological innovations that distinguish our company,” says Marco Colombo, head of the technical department at IMSA. “In order to put our design ideas into practice, we use top-quality components that can guarantee the best performance and reliability over time. For example, NSK has always been our point of reference in motion control throughout the evolution of our machines. The availability of optimal-quality NSK bearings, ball screws and linear guides has allowed us to build the highest performance machines in our sector.”

One of IMSA’s most recent innovations has been the development of a rotary-tilting table, which allows the machining of moulds in five axes using just one clamping position, further reducing manufacturing time. MF1000-3T EVO, a deep-hole drilling machine for small to medium automotive moulds up to 2.5 tonnes in weight, is the first model to be equipped with this solution. Here too, IMSA is using NSK’s latest-generation solutions to achieve the very high performance required.

“To transform axial movement into rotary movement, we use two 63 mm diameter NSK ZSS series ground ball screws,” says Colombo. “Compared with the ball screws of previous generations, they guarantee greater rigidity and perform better in terms of speed and load capacity. As a result, the machine’s working axes can move at feed rates of up to 30 m/min.”

For further information
www.nskeurope.com