Dugard Eagle 400 lathe provides universal turning solutions to Inca Geometric

Inca Geometric which is based at Chartham, near Canterbury, is a special purpose machine tool and general engineering subcontractor so when it checked out the specifications for the type of universal lathe it needed, build quality, capability and support, was carefully matched against value-for-money. Said Inca Geometric Works Manager, Tony Clifford: "There was very little we could criticise in the Dugard Eagle 400 when compared to other machines available, and that includes certain machines that were considerably more expensive." One of the reasons for build quality being very high on the agenda for Inca is a long-standing contract for precision turning components for a customer in aluminium, brass and perspex that can be up to 550 mm in diameter. Produced in batches of up to 50 a month, the company faces strict quality requirements for the 'as turned' surface finish, with the added geometric demands for concentricity, flatness and parallelism. The heavy duty, 9.5 tonne Dugard Eagle 400 has a swing over the bed of 770 mm with a 570 mm cutting diameter. The 26 kW spindle is powered by a two-stage gearbox giving up to 2,500 revs/min and the high stability, rigid box ways ensure maximum accuracy and that surface finish is maintained under cutting conditions. The universal Dugard Eagle 400 lathe was installed in May 2008 and such was the capability of the machine and the support from C Dugard, that in August a pre-owned Quaser vertical machining centre with fourth axis and Heidenhain control was installed for further general machining tasks. Some 18 months before the installation of the lathe, Inca also took delivery of a large TOS W100A horizontal boring machine from C Dugard with Heidenhain 5-axis readout to cover the 49 inch square indexing table and extending quill movements in addition to X, Y and Z. Added Mr Clifford: "We look at any equipment supplier from a machine tool perspective and the support from Dugard on all three machines has been first class. The installations were very straightforward due to the competence of the crew that had the experience for any eventuality." Inca was originally set up by the late Geoff Cain in North London in 1956, to design and produce multi-drill heads. In 1962 it relocated to Kent and added a subcontract machining facility for an automotive pump manufacturer. The company progressed into retooling special purpose machines and then in the late 60s began to design and engineer its own range of special purpose rotary and in-line transfer machines many of which are still used in production today. Among projects completed were 17 machines in the mid 70s for the Korean Motor industry, large machines for producing off-road vehicle axels and transmissions, cylinder boring and fuel injection components. With the acquisition of a foundry in Canterbury, the company employed some 220 people in its heyday. Inca has still retained its retooling expertise linked to the special purpose area and so retains many of the skills in its 30 employees involved in this area and especially provides a re-engineering service for machines, multi-heads, indexing tables and fixturing in addition to its subcontract machining services. Customers are widespread covering the automotive, transport, power generation, pump, defence, lifts and escalator and marine sectors and the ability of the business to operate as a general machinist means a wide range of work passes through the doors; from miniature ball stops to generator bed frames some 6 m by 2 m. In the summer, Inca's engineers even rebuilt a 21 spindle and two 45 spindle multi-tapping heads for an automotive customer during its shutdown and also rebuilt two cylindrical grinding machines and four hydraulic presses for an off-road vehicle manufacturer. The company is very service based, another reason for the installation of the Dugard Eagle 400 and Mr Clifford describes how they recently had to pick up a large shaft from a power station at midnight, reverse engineer a new part, machine it on the lathe and have it back to the station by 6 am the following morning ready for its reassembly. "This is where a flexible, universal machine and the Fanuc control pays dividends," he said. A prime example of its production capability is the machining of an aluminium wheel style component from billets around 555 mm diameter by 41.5 mm thick. Originally they were cast but blow holes were a common problem. In recommending the switch of raw material to a blank, Inca redesigned the component with its central boss as a separate item to save material which is then machined separately leaving stock material for finish turning. The boss is then screwed and secured with Loctite into the bore of the main wheel and then finish turned as an assembly with the addition of a screw cut thread on the OD. Produced in four operations, the profile of the wheel style component is initially roughed out and bored to accept the central boss then re-chucked and clocked true for the rear to be machined which includes a large scalloped recess in the face. The rear face is then finish machined and then clamped to a face plate locating precisely from the bore ready for the final profile, to be faced and turned. The boss is then finish turned true to the bore and threaded. The part which can be machined from either aluminium or brass and takes around 1 hr 15 mins to produce but as Tony Clifford points out, it is all a matter of product quality not a race against the clock. Occasionally parts are required in perspex which means very high levels of care have to be taken to prevent scratching or marking. Said Ann Cain, managing director: "We are still very much a family business that has kept its skill base and, as such, we can turn our hands to almost anything. This is why we need such high levels of flexibility with any machine we install. Our biggest problem is finding the skill levels to tackle one-off jobs, so we are always keen to train apprentices and, in fact, one who joined us when he was 16, is still here at 67."