After being officially unveiled at the AMB Stuttgart show in September, Star GB brought a prototype model of its brand-new SD-26 sliding head machine to its open house in November so UK customers could take a closer look. Dave Tudor reports. 

Supported by 12 technical partners – J&S Engineering, Wogaard, Filtermist, Filtration Service Engineering, Floyd Automatic, Ceratizit, Firetrace, SolidCAM, Arno, LNS Europe, Trent Oil Lubricants and Renishaw – Star GB’s November open house event clearly generated much interest in the industry. Representatives from 75 companies attended with Star taking double digit orders during its three-day duration. 

Technical partners aside, there was plenty of technology on show from the host, particularly on the software side. This included the latest versions of its NC Assist CNC template-based program editor and the Star Monitoring and Operator Support System (SMOOSS-i) which facilitates remote machine status monitoring via smartphone, tablet or PC. 

Also, being demonstrated on several machine models was Step Cycle Pro (SCP), Star’s swarf management system designed to combat the challenges of stringy swarf produced when machining difficult to chip materials such as stainless steel, aluminium, copper and Inconel. 

SCP can be used on the main, sub, and any live tool spindle simultaneously and is centred around an ‘air cut’ chip breaking process driven by oscillation of the axis in synchronisation with the spindle rotation cycle. 

But undoubtedly it was the new 9-axis (five main spindle, four sub) SD-26 Swiss type automatic lathe that drew the most attention. On show was the Type S variant, but there are actually three other models in the series – Type G, Type E and Type C. 

This was the SD-26’s first showing in the UK. Capable of tackling the most complex of machining tasks and with a wealth of features such as twin programmable B-axis heads (Type S), the 26mm diameter capacity machine is ideal for manufacturers that work regularly with 1 inch diameter bar. With the lion’s share of Star machines covering the 20mm to 32mm bar diameter range, the new addition occupies that middle ground perfectly. 

Spot the difference

Let’s outline the major differences between the four SD-26 types: 

The SD-26 Type S model is the highest specification machine with twin programmable B-axis heads: B1 has four front and four rear tools and B2 provides an interchangeable cartridge station which can accept twin mill/drill spindles for a total of six spindles. 

These can be used for machining angular features or for housing a double threading whirling attachment for complex bone screw manufacturing for example. And, with two separate heads, two different bone screws forms and leads can be produced on the same component as part of the same machining process. Star has high hopes for the SD-26 in medical applications. 

Alternatively, a twin sleeve holder for high-speed electronic spindles can be incorporated, enabling complex 3D 5-axis profile milling. 

But not everyone will need twin B-axis heads of course, so while the other three SD-26 variants have progressively ‘lower’ specifications, this certainly doesn’t detract from their usefulness in real-world machining applications. 

Type G doesn’t have dual B-axis capabilities but instead it features a programmable 5-axis simultaneous B1 head with four front and four rear facing tools as well as an additional two cartridge positions for various attachments. 

Type E is the same specification as Type G but with a lower spec FANUC 32iB CNC for applications that don’t require 5-axis profiling capability. Last but by no means least, Type C replicates the Type E specification but with FANUC 0iTF CNC and a manual B-axis head. It features the same number of tools as the S, G, and E types but at a lower price point. 

Types S and G are simultaneous 5-axis with FANUC F31iB5 CNC; and Type E and C are 4+1-axis. Type C is also equipped with an angle adjustable swivel unit. 

Despite their operational differences, all models ship with many common features across the entire range such as: guide bush/non-guide bush capability; high-speed/high-power spindles (main- and sub- 10,000rpm/7.5kW/5.5kW); high-pressure coolant manifolds; up to 10 back-working tools; 100mm deep hole drilling capability; and up to 154mm maximum part length for front ejection. 

Machine highlights 

“One of the SD-26s highlights is undoubtedly its tool holding capacity,” explained applications manager Phil Bellamy. “40 tools can be accommodated in total with much of the extra room integrated into the back-working aspects of the machine which not only helps keep the overall footprint to a minimum but also allows excellent front-end access for swift changeovers and automation. A really useful feature is the addition of two independent dedicated turning tool holders for back-working making a total of ten stations.” 

At 2m, the SD-26 is quite a tall machine but this helps accommodate the extensive tooling capacity available in the machining envelope. Everything is conveniently laid out and within easy reach. The overall dimensions are a compact 2.55m (W) x 1.3m (D) x 2m (H) so this is designed with a small footprint to squeeze into often space-strapped shop floors. The overall weight is a reassuring 3,600kg. 

To guarantee optimal and consistent operation whatever the conditions, temperature sensors are strategically placed on sections of the machine body casting. This offers flexible thermal displacement correction based on real-time thermal expansion data fed back from these sensors. 

Get in early

It’s very early days for the SD-26 sliding head machine but despite the fact that the open house machine model was only a prototype and production machines aren’t expected until April/May 2023, Star GB has already taken an order for the new addition. 

And that accolade goes to Hertford-based precision subcontractor Qualiturn Products Ltd. The deal was actually sealed at the IMTS show in Chicago last September. Managing director Nick Groom takes up the story. 

“I didn’t attend the show personally but my production director Steve Aulton saw the SD-26 on the Star stand and placed the order,” he affirmed. “We’ll confirm the full configuration soon but we opted for the Type S model. 

“Technically this machine just make sense, offering so many options and configurations,” he added. “I am buying for solutions and options across a variety of sectors but also, importantly, to demonstrate to our customers that we are continuing to invest in the very latest equipment and technology available. 

“We’ve purchased many Star machines over the years and from both a technical and service perspective I’ve never been let down so I’m more than happy to continue. With its 26mm capacity, the SD-26 will sit perfectly between our SR-20 and SR-32 machines.” 

Qualiturn will take delivery of its new SD-26 mid-2023. 

Continued investment in the face of adversity 

Star GB’s managing director Steve Totty was naturally delighted with the success of the open house: “This was an exceptionally well-attended event and it effectively continued the momentum of the MACH exhibition last year, demonstrating just how buoyant the manufacturing industry is throughout Britain and Ireland,” he commented. 

“While the world economy continues to face real challenges, the visitors we welcomed to our Derby facility showed incredible positivity with ambitious plans to continue investing in the future of their businesses. 

“I’d like to personally thank everyone who supported the open house – the visitors who travelled from near and far to join us, our technical partners who showcased their latest developments and the Star team who worked tirelessly to make the event a success. 

“After a record year, we look forward to the exciting times ahead in 2023 and we are proud to continue supporting our customers as a market leader in sliding head lathe technology.”

Star GB
www.stargb.com

Qualiturn Products
www.qualiturn.co.uk

Production Engineering Solutions
www.pesmedia.com

Author
Dave Tudor