The installation of a multi-tasking machine tool at a scientific instrument maker has brought 'one hit' machining capability that extends to producing milled components from bar.

Combining milling and turning keeps costs down The installation of a Mazak Integrex 200 IIIS multi-tasking machine tool at its Tunbridge Wells, Kent factory has provided scientific instrument maker Bellingham and Stanley with a 'one hit' machining capability that extends to producing milled components from bar. 'The performance of the Integrex since its installation in March 2005 has confirmed that this is the way forward,' says Mike Banks, production director. 'Precision machined components, including milled components previously allocated to other machines, are produced from bar in a single set-up, with the Integrex capable of running unmanned in a lights-out environment.

This is streamlining the 'design to manufacture' process, while the savings resulting from rationalising our materials requirement is another contribution to keeping our costs down.' Bellingham and Stanley is a world-leading manufacturer of refractometers and polarimeters.

However, while new designs continue to emerge for export to all parts of the world, this long-established company faces a serious challenge from low labour cost economies.

This means that maintaining low overheads is crucial, and with this in mind Banks has introduced far-reaching changes to the way in which the ISO 9001:2000 accredited company makes its world-class products.

'While the traditional 'big batch' approach ensured the minimum of machine set-ups and changeovers, it all too often resulted in parts 'a' and 'b' arriving in the assembly area while part 'c', the item needed to join them together, was nowhere to be found,' he says.

'It was still in the materials store where rack upon rack of expensive raw material - stainless steels, aluminium, brass and plastics - was awaiting its turn to be machined.

This was matched at the other end of the production process by an equivalent inventory of high value finished components awaiting final assembly.

In effect, this was 'dead' money that could be put to better use.' The imbalance between production and delivery to the customer, and its impact on cash flow, prompted a more flexible response to market demand.

This entailed moving away from 'pushing' work through in large batches and the introduction of a 'pull' system targeted at providing customers with on-time delivery of cost-competitive products assembled on a kit-of-parts basis.' 'It is not possible to change everything in one go,' says Banks, ' But we began by upgrading our CNC machining capability, initially with a small turning centre equipped with sub-spindle, C axis, tool probing and driven tooling.

We equipped our VMC machines, where appropriate, with quick changeover vices, workpiece and tool probing, and pallet changing systems.

We updated our CAD/CAM capability, which is now fully interactive, with DNC downloading of programs on demand from the operator.

More recently, we introduced lean manufacturing techniques to ensure that we machine only what we need, assemble only what has been ordered and deliver a completed instrument as quickly as we can.' The new Mazak CNC machine delivers a fully machined workpiece in one 'hit', which cuts lead times and boosts productivity.

'Of course, it is a major investment for a business employing 50 people,' says Banks, 'But without this level of technology we will be unable to maintain our market-leading position.' The main feature of the bar-fed Integrex 200 IIIS is its combination of 22kW, 5000 rev/min main spindle, 18.5kW, 5000 rev/min second spindle, and upper turret.

This caters for turning, milling, contouring with the C axis, off-centre machining with the Y axis, and milling of angled surfaces with the B axis.

The 15kW, 12,000 rev/min rotary tool spindle moves through 225 deg (B axis) in positioning increments of 0.0001 deg, while the 200mm chucks have indexing increments (C axis) of 0.0001 deg (main spindle) and 0.001 deg (second spindle).

Maximum machining diameter is 660mm and maximum machining length is 1016mm.

'Linking this high specification machine with an 80 tool carousel, quick change collet chuck, and standardised tooling and materials means we can change from job to job in minutes rather than hours,' says Banks.

'This capability is reducing costs in manufacture and providing a far more flexible platform for producing the many precision engineered components used in our instruments.'