Tuesday, February 27, 2007

CNC lathes' conversational programming wins

Conversational programming, which is very easy to learn, allows a subcontractor to program most of its CNC lathe jobs on the shop floor - even quite complex work.

The combination of very high skill levels, a detailed understanding of aerospace industry requirements and materials, plus the ability to respond quickly, form the backbone of the business of John Harper and Steve Price, two director partners of Paragon Engineering and Logistics. Paragon is a 26 people subcontracting company formed in 2000 in the UK by two ex-Lucas Aerospace senior managers who have enjoyed ever-growing success from a strong customer support policy. And, having gained its spurs from strict attention to detail, the business now devotes its energies to 'Aerospace Alley' a particular area of the Midlands that forms a corridor of aerospace companies that brings Paragon's customer base to within two or three miles of its 6,000 ft2 machine shop in Bushbury, Wolverhampton.

As a result of being close at hand, the two directors almost run a 'doorstep' service and are in and out of customer plants on a daily basis, creating a high profile of no job too small or complicated.

Having installed five Colchester-Harrison Tornado lathes in two to three- axis variants, Paragon is geared to flexibility.

It needs it - no job lasts longer than two days and batches of parts produced on standard tooling rarely exceed 20.

As Harper explained: 'We live and breathe the aerospace industry and it's jump in the car, go see the customer, come back with drawings and respond.' Paragon machines a wide variety of materials from aluminium to tough experimental steels.

Quite often parts are for development, spares or ramp-up and ramp-down volumes.

For some customers, Harper explained: 'We have to trial and develop speeds and feeds on top secret materials to enable the customer to machine it'.

'This is where our high skill base comes into its own and the machines we use have to be rigid and stable.' The company, for its size, has a very flat management structure, Harper and Price are very much 'at the helm' with everyone else in support.

'No foreman or chargehands,' said Harper, 'our people are so skilled that they are pretty well self-motivating.' The company runs a single day shift from 8 am to 8 pm - no one clocks in or out and people arrive and depart to suit their home lives or traffic conditions.

They know what they have to do and being responsible for their working lives gives them a feeling of running their own business.

For us it pays off too because there are no problems and they respond when we need it,' he said.

Each Tornado has its own setter operator and most programming even for the difficult parts, is carried out at the machine.

'The in-built Colchester Lathe developed Manual Guide i conversational programming software is a very practical package,' said Harper, 'The setters find it quick to learn and they almost play tunes on the control - you must remember, most materials are special so we can't afford scrap and as these guys are setting day after day they are very sharp.' The toolpath verification is ideal when producing a single part enabling the copy and paste of sections of programs when needed.

He explained: 'We have no need to look for cycle time - we look for good work - right is the only way and consistency from part to part is paramount especially on development work and we get this from the Tornado machines.' Most turning jobs on the Tornados tend to be within 125mm diameter by 250mm long and the company buys its exotic material by the metre, half metre or even a single billet from designated suppliers.

Very rare is it that the same batch is machined twice and they vary between a whole range of shaft sizes, gear blanks, end caps and housings.

To which Price added: 'With current JSF project work, this means we often get orders for one trial part.' The first two Tornados a T120M and T220M with 54mm and 65mm diameter bar feeds and driven tools were bought as a package in 2002 with additional capacity derived from a previously owned Tornado 110.

In the summer of 2006 new two-axis T2 and T4 lathes were installed, the latter to provide a larger capacity when needed with a 230mm turned diameter by 450mm long.

Bar capacity is 54mm diameter.

The company also has extensive CNC milling and a full grinding process capability covering surface, internal cylindrical and centreless, but for turning has standardised on Colchester-Harrison.

The directors maintained this devotion to Colchester-Harrison for turning as it provides high levels of familiarity between machines, helps with service support and with sales and service operating out of 600 Centre in Shepshed, said Harper: 'This puts them right on our doorstep because we cannot afford a machine to be idle.'