Where Citizen lathes score, says a subcontractor, is that through our retained skills we can quickly move to cam or multi-autos and special purpose, a resource that is seriously lacking today.

Based in Merton, very close to Wimbledon, in South West London, Tenable Screw Co is no stranger to the public eye for its small part precision machining business. Just next door are the studios where police soap drama 'The Bill' is filmed and quite often the villains of the plot can be seen on camera attempting their escape through the high technology machine shop dodging down the gangways between 28 CNC machine tools with the stars of the show in hot pursuit. Of the 28 machines, 24 are citizen cnc sliding head autos of which four now stand out in the new silver livery of the K-series and Tenable Screw's machines were the first to be installed in the UK.

Far from being a film set, although the 66,000ft2 machine shop is Tardis-like once inside, the GBP 6 million turnover company has set its stall out to mix both old and new technology equipment and machining methods.

Described by brothers, managing director Simon and co-director Nigel Schlaefli, as having a very prized capability with a workforce of 110 people, they reckon to have a solution for all customer demands through the still originally owned family business.

Indeed, a testament to their skill-based activities reside in the foyer showcase in Deer Park Road where a Hornby 'Golden Arrow' model train takes centre stage.

Although a saddened Nigel Schlaefli reflects it has all gone to China now, Tenable Screw made some 60 different parts for over 35 years such as lamps, wheels, Pullman tables, buffers, screws and fittings for Hornby.

While the Merton subcontract machine shop covers some 66,000ft2 Tenable Screw also has a production site in Coventry for second operation machining with 12 people serving the Midlands and North of England and another in Marlborough for high volume CNC, cam machine and special purpose machine production.

Each of these sites cover 50,000ft2 and house a massive plant list boasting some 254 individual machine tools.

In addition to the 28 CNC machines 40 are single spindle cam types, 27 are multi-spindle autos, 65 Escomatics and, unbelievable for a subcontract machining operation, 91 are rotary transfer and special purpose machines from the likes of Hyrdromat, Wurth and Gruffat and a number of Variomatics.

Commenting on the menagerie of machines, Nigel Schlaefli smiles.

He then quickly points out, with the availability of floor space and machines all bought and paid for, they have developed a leave it set policy for the annual repetitive contracts.

Many of these machines are treated as if they were jigs and fixtures and simply disconnected after the production run and mothballed as a fully tooled set up for the next order.

'We can still install a cam machine or a special purpose machine faster than we could ever reset it - let alone track down the tooling.

We just press the button, perform a first-off and away it goes,' he says.

According Simon Schlaefli: 'With the Tenable Screw policy of having one foot in the CNC camp and another in more conventional machine tools, we can easily provide a complete product life service to customers.

This is something of a niche operation generally no longer available in the UK - offering prototype, pre-production, ramp-up and ramp-down production operations using the flexibility of CNC.

This is where the Citizens come into their own and through our retained skills we can quickly move to cam or multi-autos and special purpose, a resource that is seriously lacking in the competitive area of the subcontract sector today.' He maintains that this capability means they can go head to head against Chinese and Eastern European companies.

'Our lead times are far shorter than the boat on the water and as our materials are all European sourced, we are always able to adhere to the customer specification.

Our turnover and profitability reflect the confidence customers have in us to deliver.' Tenable Screw started its association with Citizen CNC sliding head autos some 15 years ago with a pre-owned machine.

The company ordered its first new B12 in 1998 and has progressively installed three Citizens a year right up to this year, only breaking the programme by ordering three K12 and one K16 machine.

Simon Schlaefli is quick to point out the reason for such a concentration on one machine builder for sliding head lathes as being back up and support.

And he admits the constant development of the range means there is always a justification to buy more.

As he cites: 'Compare the B12 to the new K-Series.

The new machine has faster servo reactions, the control is more advanced, you can drill, turn, mill, hexagon broach and thread with two tools engaged at the same time.

We are one of the very few UK based companies that produce high volume electrical connector block geared up to produce at very competitive prices against overseas competition.' He then follows on to describe a prime example.

'With the new K12 we have reduced cycle times on one part from 55 secs to 36 secs which is a dramatic cost saving and more important, reduces lead times.

We have further advantages with improved access for setting, consistency of production is first class which helps on SPC analysis and we can run out of normal working hours giving higher machine utilisation.

We regularly hold +/- 0.03mm tolerances on a whole range of parts between 2mm and 13mm diameter.' Simon carries on that: 'Single cycle machining is a big advantage and the speeds and feeds available with the inherent build quality of machine means we can work on a wide range of materials and constantly reduce cycle times or tailor the process to give ourselves uninterrupted shift working which becomes more critical as volumes mount.

And we have found with all citizen machines the residual value is excellent because they are always in demand which makes it a very cost-effective machine to own and run.' Formed in 1940 by father and now chairman, George Schlaefli to make rivets for Wellington bombers and parts for electricity meters, the company now produces an amazing range of components covering connectors, consumer and automotive electronics to Tier 2 and 3 suppliers, wiring harnesses, armature and solenoid parts, aerospace connectors, inserts for moulding and even musical instrument components.

Today, some 20% of production is exported with parts going to America, and surprisingly to Malaysia and the Czech Republic, which clearly defines the competitive working of the business.

Simon Schlaefli is adamant the skill of his people is the mainstay of the business.

He says: 'We can develop methods which may be traditional cam or multi-spindle techniques but when you apply the concept to a modern CNC sliding head machine you will be amazed at what can be done.' He is adamant: 'You will not get these solutions out of the Far East and how many subcontractors in the world today can go from producing a few very complicated prototype parts using a Citizen as a flexible CNC machining centre that may take a week to develop the process, then run them through pre-production then ramp-up for higher volumes.

That is what many of our customers rely on - our total flexibility, from a single source and we have continuously invested to achieve that,' he concludes.