Tool maker adds HMC to cope with chuck demand

Another HMC with twin pallet changer has been installed at a toolmaker's factory to meet increased European demand for its workholding products, principally chuck jaws for lathes.

Another Daewoo horizontal machining centre with twin pallet changer has been installed at the Long Crendon, Aylesbury factory of Thame Engineering to meet increased demand throughout Europe for its workholding products, principally chuck jaws for lathes.

The upturn in business is despite increased competition from the Far East.

The British manufacturer saw sales of its standard product range grow by over 20 per cent in 2003, while Thame's bespoke fixturing solutions, some using vacuum or freezing techniques and others in-cycle repositioning, is set to rise during 2004 now that a general upturn in UK manufacturing is becoming apparent.

The new machine, a Daewoo ACE HC400 supplied through UK agent, Mills Manufacturing Technology, was purchased primarily for the same reason that the previous ACE horizontal machining centre was bought, namely an ability to support half a tonne on each 400mm2 pallet.

According to Thame's managing director, Peter Mason, they were the only machines on the market in the same price and size category that could carry such a heavy combined load of fixtures and workpieces.

Added technical director, David Handley, "Daewoo was sure that the 400 kg maximum table load was very conservative in its brochures and was prepared to guarantee a figure 25 per cent higher.

Since the last ACE was installed, we have not had a single problem with the pallet system, despite regularly loading them up to500 kg.

"There are other advantages of staying with the same supplier, such as operator familiarity and the ability to swap programs between the machines.

This we do regularly as they are set up almost identically." Thame uses its own design of high capacity workholding system for machining up to 48 jaw blanks at a time, 12 on each side of a tombstone fixture, which alone weighs 300kg including the clamps.

For larger components, bearing in mind that they start out as blocks of solid steel, the material can weigh 200kg, taking the total pallet load to its extended maximum.

Each face of the cube can accommodate different components, on which two operations are performed, serrations being hobbed or ground on a separate machine.

The ACE horizontal, pallet-change machining centres are around 40 per cent more productive than Thame's previous single-pallet, vertical-spindle machining centre for the series manufacture of standard workholding products, four fifths of which are for turning, although sales of clamping systems for prismatic machining applications are increasing.

Part of the machine's productivity advantage arises from being able to set it to operate unmanned between shifts and the fact that it does not need to have the operator in attendance other than to load/unload and set up.

The horizontal spindle provides improved control of swarf, and through-tool coolant maximises drilling performance.

A previous manual chamfering operation has been brought in-cycle, cutting unit production cost and improving the consistency of finish.

Overall, product quality has been enhanced.

Batch sizes are typically up to 1,200-off for the production of standard jaws, which demand efficient machining methods so that they are cost competitive.

A new product range launched at MACH 2004 for rotational part workholding, called Quick Change Jaw System and intended for rapid changeover from one diameter to another, will also be produced on the ACE machines when production volumes have risen sufficiently.

Thame has around a dozen CNC machines of various types, including lathes, and a number of conventional machine tools for 'jobbing' work.

In 1998 the company acquired a Daewoo Puma CNC turning machine through Mills Manufacturing as a direct replacement for an old NC lathe.

A key attraction of the Puma was its large 550mm turning diameter, providing capacity to turn jaw sets for vertical turning lathes.

However, the Puma is also used for bar work, utilising Thame's own bar pulling device for batches of up to 400 components.

Mason commented, "We felt that the lathe offered good value for money, as it is capable of tackling a wide range of work.

The integrated setting probe makes tool set-up straightforward, while availability of constant surface speed ensures much more consistent finish compared with our old machine.

Our next purchase will be a mill-turning centre with a view to producing jaws in fewer operations, and some other products such as adaptors and connectors in one hit.

We are also interested in using such a machine for the manufacture of our new Inogrip range of lathe clamping system products currently under development at our German subsidiary, which will reduce the required clamping pressure to one tenth, avoiding tri-lobing of tube, and also minimise the amount of material needed for gripping." Concluded Handley, "We have been very satisfied with the performance of all the Daewoo machines.

Service back-up from Mills Manufacturing has been very good and the training has been excellent.".

Back to top