High pressure cooling system on a CNC sliding head automatic lathe provides high levels of security of process to cover the wide range of materials such as nickel alloys, brass and titanium.
Over 95% of the small precision machining capacity between 4mm and 32mm diameter at GBP 1 million turnover Riverside Precision Engineering (RPE) is generated by single operation 'one-hit' cycles. Located in Blackburn, in the heart of aerospace subcontracting country, RPE's order book is dominated by medical, marine equipment, hydraulics, furniture and brewing customers. Most of the up to 32mm diameter components supplied to the 50 or so long-standing customers are produced by double shifting three citizen cnc sliding head autos, an L20-Vll bought in 2001 and the latest M32-lll and L32-Vll machines installed in November 2004 and January 2005 by NC Engineering of Watford, UK.

And, as is becoming more common with leading contractors using advanced sliding head technology, RPE's joint managing directors Michael Ditchfield and Scott Whalley are increasingly involved with in-depth consultation with customers on design for production and application issues.

As a result of applying their advanced machining knowledge, RPE customers are able to achieve either higher performance or improved application of components or, enjoy more cost-effective pricing gained by applying the advantages of Citizen's fast developing machining technology and latest available tooling solutions.

RPE, which is now running at the forefront of small part turning by offering advanced production machining, started as a toolmaking business 15 years ago using manual machine tools.

A local furniture maker requested batches of 500 or so parts against a target price that set RPE on the path to progress by using automated capstan lathes.

Orders followed for diving equipment components, resulting in the first two CNC lathes installed and, eventually, a second-hand Citizen L16-lV sliding head auto was purchased as the only way to become more competitive and meet customers challenging cost down targets.

The Citizen L16 is well remembered by both directors who describe it as being very effective on small part machining cycles due to its twin turret configuration.

But according to Ditchfield, it could never come anywhere near the capability of the modern Citizen lathe.

In 2001 the company moved into its current 5,000ft2 premises and a new Citizen L20-Vll was quickly installed to satisfy a large contract that RPE describes as having to 'hit the ground running' to meet the delivery date.

Needless to say, it proved to be a highly successful venture.

Said Ditchfield: 'But at the time we could not even think about being trained on the L20 as we had two months of continuous production to get out the door so it was some time before we finally learnt how to get the best out of the machine.' Describing the business, Whalley maintained that forward planning is very difficult and they have become very accomplished at reacting quickly to customer demand.

That is why, he said, the latest Citizen M32 has 'all the bells and whistles'.

The machine was ordered with gantry off-load, Cool Blaster, the 2,000 lb/in2 programmable high pressure cooling system and NC Engineering's Alarm Alert which automatically calls for attention when unattended if the cycle is stopped for any reason such as batch completed, bar jam or tooling fault.

The NC Alarm Alert tends to be used when running unmanned and is connected to Whalley's mobile phone.

'It is really proved its worth over weekends when running against the clock to deliver critical components,' he maintained.

But it is the Cool Blaster that really provides a bonus and high levels of security of process to cover the wide range of materials such as nickel alloys, brass, titanium, 303 and 316 stainless steel, plastics, acetal and nylon the company often has to machine.

Said Ditchfield: 'Without Cool Blaster we could not effectively machine half the parts we have to produce and on one particular 'banjo' component, which has awkward internal grooves, swarf could be a big problem that would compromise the operation.

Cool Blaster solves all these problems.' batch sizes tend to vary between 100 and 20,000 and Citizen machine changeover times vary between two and six hours.

Because of the advantageous tooling capacity of the M32, RPE tends to leave common tools permanently set on the machine to speed changeovers.

Ditchfield maintained that the high speed cycle check on the latest control system of the Citizen is invaluable when programming at the machine, and takes any frustration out of proving cycles.

RPE also make use of the CNC Editor to edit programs and optimise cycles on a remote PC prior to setting a new job.

As the system totally replicates the control system it provides exactly the same visual appearance and program data which is retrieved and transmitted between machine and the PC by wireless link.

As Ditchfield outlined, they are currently considering adopting the Citizen Alkartpro off-line programming system from NC Engineering which would completely take program generation away from the machines.

The inclusion of the fully programmable gantry off-load on the latest M32 has proven to be more of a boon than originally thought, especially on components up to 180mm long.

Says Whalley: 'With the unload fingers able to grasp the component directly from the subspindle, rather than adding a delay to the cycle for the spindle to eject parts to the normal part collector, the unload cycle can be carried out while the turret and gang tooling slides are simultaneously working on the next component in the main spindle.

By getting hold of the parts, any possible chance of damage is taken away and with the added power of Cool Blaster, this ensures we have clean, swarf free parts ready for final cleaning and dispatch.'