Mills CNC, the sole distributor of Doosan machine tools in the UK and Ireland, has recently supplied a new Doosan VC630 5AX five-axis machining centre, equipped with a Heidenhain control, to hi-fi design and manufacturing specialist, Linn Products.
The machine has been installed at the company’s factory in Glasgow and is being used to produce a range of precision parts for Linn’s music systems. These components include machined-from-solid aluminium enclosures that comprise a lid and base for the company’s range-topping Klimax systems.

Prior to investing in the VC630 5AX, the machining of these enclosures was subcontracted, and while this situation was satisfactory it had its drawbacks and was always considered to be temporary. The arrangement was superseded by Linn’s desire to become more self-sufficient and vertically integrated, with the decision taken to commence machining the Klimax metalwork in-house.
Explains Fraser Crown, Linn Products’ operations architect: “The more of our manufacturing processes we can bring in-house, the better able we are to manage, control, optimise and ultimately improve them. Linn does not mass produce products; every product we manufacture is built to order. This can potentially cause scheduling and delivery fulfilment issues when relying on subcontractors who, quite naturally, prefer to handle larger and more predictable batch-type work.
“As part of our commitment to continuous improvement, it was a natural progression for us to look at bringing machining processes in-house, such as those employed to manufacture our enclosures,” he adds.
To enable Linn to manufacture all its Klimax metalwork in-house, the company needed to acquire additional machining capability. Linn is certainly no stranger to CNC machining and, some years earlier invested in a three-axis Doosan DNM650 vertical machining centre from Mills to manufacture a range of parts. Since being installed, the machine, according to Crown, “hasn’t missed a beat” and is working near peak production.
With regard to its next investment, three key questions initially confronted Linn: what type of machine tool would best produce the enclosures; which manufacturer would be able to supply the machine, and what support could they provide; and how quickly could Linn develop a reliable and repeatable machining process?

Linn’s ‘milled from solid’ enclosures feature in both the Klimax DS and Klimax DSM streamers, the Klimax amplifier, Klimax Exakt, and the Radikal power supply for the Klimax LP12 turntable. The enclosures are machined (internally and externally) from individual solid aluminium billets. Internally machined features include a number of separate and isolated chambers (divided by walls) where audio/electronic circuitry and power supply units are housed separately. The back of the enclosures contain a variation of machined holes for output and input connectors and ports.
All exterior faces of the enclosure are machined to a mirror-like finish, with the top and bottom being finished using a large diameter fly-cutter (cutting) tool that is able to face mill the entire surface in one pass to produce a uniform finish. “Surface finish imperfections, however small, are not acceptable as they would show up after the enclosures have been anodised,” states Crown.
To meet Linn’s manufacturing imperatives and quality standards, the company researched the market to identify the types of machining centres available.
“We wanted the machine to meet our immediate and future requirements, which is why we looked at large-capacity five-axis vertical and horizontal machining centres,” says Crown. “Although we do not machine parts in high volumes, flexibility, reduced set-up and cycle times, which are key advantages of five-axis machine tool technology, are important to us.
“We ultimately decided on a vertical machine with full five-axis simultaneous machining capability because it enables each side of the billet to be produced continuously without the need to remount the job,” he continues. “As a result, we negate any incremental dimensional inaccuracies and poor finish quality. We believe it will provide us with far more flexibility going forward. Furthermore, for certain machined features, most notably where the front panel display is located on the enclosure lid, we knew that using five-axis simultaneous machining capabilities would enable features to be machined reliably and accurately. In reality, the seamless five-axis movement which creates the ‘Klimax smile’ is dimensionally perfect, has a faultless finish and it is a joy to watch being machined.”

Linn already had a good relationship with Mills CNC following its investment in the Doosan DNM650 vertical machining centre five years ago. Discussing its latest requirements with Mills’ sales and technical staff, Linn decided to invest in a large-capacity VC630 5AX machine with Heidenhain CNC.
Owning a large-capacity machine means that Linn can produce a wide range of components – big and small. The decision to opt for the Heidenhain control (favoured by many mould tool and die makers) was taken for its ease of use and on-board functionality – especially its ability to help machine complex 3D surfaces and curved contours. The VC 630 5AX has a large working envelope (650 x 765 x 520 mm in XYZ), and a 32 kW/12,000 rpm direct-drive spindle.
Bringing any machining process in-house means there is an inevitable learning curve. Add to that the need to get to grips with the Heidenhain control (Linn’s Doosan DNM650 machine is equipped with a Fanuc control), and the curve becomes naturally steeper. However, the skill and experience of Linn’s operators and programmers, combined with technical and applications support (including training) provided by Mills CNC, has helped the company develop a secure and reliable machining process for its enclosures. Further refinement to fully optimise the process is ongoing and part and parcel of Linn’s continuous improvement ethos.
Concludes Crown: “The new machine is working well and we have found that having five-axis machining capability in-house makes us more productive and flexible. We are also able to respond, from a machining perspective, much more efficiently and effectively with regard to product design upgrades and modifications.”
For further information www.millscnc.co.uk

Rapid prototyping is often regarded as being synonymous with additive manufacturing (commonly termed 3D printing) technologies. However, a compelling case can also be made for CNC machining and injection moulding as rapid prototyping technologies, at least argues Stephen Dyson (pictured) of Telford-based specialist rapid prototyping provider Proto Labs.

Increasingly, rapid prototyping is a strategic capability. Being the first to market with a new product or refinement confers a competitive edge, and being able to quickly develop prototypes gives an important advantage in that race to be first. And once earned, a reputation for innovation leadership tends to stick: customers will defer buying decisions until they have had a chance to see the offerings from those businesses with a track record of delivering market-defining products and product enhancements.
For certain projects, rapid prototyping is a management discipline. In the race to be first, there is no point having roadblocks or bottlenecks in key design and development processes. And the more strategic an end product is, the more important it becomes to make sure that prototypes and their designs do not loiter at the back of the queue.
But rapid prototyping is also a technology decision, and as rapid prototyping increasingly moves centre-stage in the push to be first to market, that technology decision is becoming increasingly important.
Put another way, the selection of the wrong prototyping technology can have a lasting and damaging effect on both time-to-market and product quality or reliability. This is because, in a world where rapid prototyping is often synonymous with the use of additive manufacturing technologies of various types, manufacturers are in danger of becoming overly reliant on it as a prototyping technology. Sure enough, 3D printing might well deliver a part that helps check form, function and fit, but where a project requires other critical attributes, such as suitability for pre-compliance testing or customer validation, other prototyping processes may be more suitable.
Prototypes manufactured using a standard 3D-printing process are produced undeniably quickly, but the resulting plastic parts may have poor strength. Stereolithography (SL) and selective laser sintering (SLS) technologies are processes that produce strong parts, but they are not always suitable for functional testing, and may provide limited data on manufacturability. In addition, parts produced through SL tend to become brittle over time, while the surface finish of parts produced through SLS tend to require additional aesthetic enhancement.

Rapid prototyping through direct metal laser sintering (DMLS) and fused deposition modelling (FDM) is generally regarded as a significant improvement in terms of physical strength, the resulting prototypes being made of various metals (in the case of DMLS) or industrial-strength resins (FDM). But as additive manufacturing processes go, FDM is quite slow and produces parts with a potentially unacceptable surface finish, while DMLS-produced parts can be expensive if requirements call for more than a handful of components. And again, indications of finished-part manufacturability are comparably limited.
In short, while additive manufacturing technologies are ideal for producing parts with extremely complex geometries that will permit the checking of form, fit and function, in many cases, post processing (such as CNC machining of certain surfaces) enhancements may be required to meet the needs of the project.
So what does that leave in terms of rapid prototyping technologies? The answer, perhaps surprisingly, is CNC machining and injection moulding; technologies that are often generally regarded as being mainstream production processes.
In both cases, the resulting parts will have the same physical properties and surface finish as the finished part, and will generally provide excellent indications of manufacturability. In short, if an important aspect of the overall development process involves testing the physical properties of parts, then a convincing case can be made for rapid prototyping through CNC machining and injection moulding technologies, especially if the prototyping process calls for small batches of components, as opposed to one-offs.
Furthermore, again in both cases, it is very possible for these technologies to be genuinely rapid. Both are capable of extensive digitisation, with the time taken to produce an injection-moulded part being further reduced by machining the requisite moulding tool from aluminium rather than steel. In short, coupling CNC machining and injection moulding as a prototyping technology may take a little longer than with additive manufacturing, but can yield vastly more useful data in terms of the conformance characteristics of the prototypes in question, as well as their manufacturability. Plus, the added cost is spread as the number of required prototypes increases.

Even so, this is not to say that there is no place for additive manufacturing within a prototyping strategy. Of course not. It is simply that a well thought-out prototyping strategy is likely to be one that embraces several rapid prototyping technologies; additive manufacturing to start with, in order to provide initial data on form, fit and function, before moving to CNC machining or injection moulding as appropriate for subsequent rounds of prototypes. The acquired data will then provide the necessary confidence to invest in the CNC machining or injection-moulding process.
Ultimately, the decision process is more complicated than a policy of using only 3D printing technology. However, as rapid prototyping becomes an ever-more strategic capability, deciding which technology to employ is increasingly worth in-depth consideration. So, if an OEM discovers that its rapid prototyping provider cannot support digitisation together with CNC machining and injection moulding capabilities, then it could be time to look for another provider which does.
For further information www.protolabs.co.uk

When William ‘Bill’ T Cox Jr talks about his business, the conversation turns naturally to the Cox Manufacturing Company’s strapline ‘Cox delivers confidence’ – and it is technology from Tornos that helps him make good on that promise every day.

Situated in San Antonio, Texas, one of three metropolitan Texas cities that make up the Texas Triangle region, Cox Manufacturing specialises in custom screw machine products and CNC turning. The company’s customer-centric legacy began in 1956, when Cox’s father, William T Cox Sr, founded the company and started making bobbins for early computer memory systems.
“We are committed to doing what we say; we don’t give up,” states Bill Cox. “Perseverance is one of our core values. We put a lot of emphasis on building systems to manage orders and that helps us to maintain blanket order relationships and ensure quick delivery to our customers. As a result of the robust processes we have in place, our customers know they won’t encounter any surprises when they do business with us.”
Cox Manufacturing was founded with his father’s bold bid to start “some sort of manufacturing company” after coming across a Swiss-type screw machine at an auction. Though he had limited knowledge about the machine and knew next to nothing about automatic screw machines and Swiss automatics, Cox was passionate about manufacturing and had a prowess for solving engineering problems. Those were the cornerstones on which he built a business that has become a leading supplier of precision machining services throughout the US southwest. Today, Cox Manufacturing supplies high-volume, tailor-made components for some of industry’s most discerning customers in the aerospace, automotive, trucking, defence and medical technology sectors.
Bill Cox’s commitment to the family business began early. After his father’s sudden death in 1968, when he was just 12 years old, his mother took him aside and explained that Cox Manufacturing’s biggest customer was interested in buying the business. Was he interested in someday running the business himself? His answer was an emphatic, “yes,” and he was off and running in his quest to learn everything necessary to continue building on the foundation his father had established. He quickly learnt to read financial statements and joined his mother in meetings with bankers, lawyers, accountants and contractors.

“I realised early on that the diversity of our customer base was limited,” he says. “Around 80% of our business was with the electronics industry. We were highly dependent on five customers buying the same product from us. I knew that we needed to learn to make other parts.”
After attending Texas A&M University for two years, just long enough to take the courses that would serve Cox Manufacturing and its soon-to-be growing customer base, the 20-year-old Cox began working full-time at the family business.
When he joined the business full time, Cox Manufacturing was using Bechler and Index machines, as well as some Swiss-type machines and Index single-spindle cam machines, but Cox was looking to the future. He began buying up used Tornos Deco machines and today owns more than 30 of them.
“The tooling and basic machine strategies are similar, so the wealth of knowledge we had accumulated with the competitor machines was transferrable,” he says. “We found that the higher precision Tornos machines were more cost effective in the long run, despite the higher capital investment, because they were more efficient.”
Cox Manufacturing took a big leap in 1980 with its move into a new building constructed on land that Cox and his mother purchased when he was still in high school.

“When I look back, it still amazes me because nothing happened overnight. We were thinking ahead by buying that land and building the facility, moving into multi-spindle machines. Today, we have 33 Deco machines, including the Deco 10, Deco 13 and Deco 20, and we still run some Tornos R10, R125 and MS-7 cam machines. However, we are gradually retiring those and replacing them with Tornos CNC machines.”
More recently, Cox bought a new Tornos SwissNano, which is turning out to be a perfect fit for his business. As a result, this visionary entrepreneur already has his eye on further SwissNano purchases.
“The beauty of the SwissNano is the access and ergonomics,” he explains. “This makes it so much easier to work with fine, small parts. A good example is a precision brass medical part with a ±10 µm tolerance. The stability of the machine and its ease of use make the SwissNano a lot more efficient than other options. Previously, we would have made this part with a Deco 10 and, before that, on an MS-7. The SwissNano is compact and it fits nicely into the same workshop footprint as an MS-7; certainly an investment that will serve the business well for years to come.”
For further information www.tornos.com

Norfolk-based Eastern Attachments manufactures construction and agricultural attachments, supplying companies such as Persimmon Homes, Taylor Wimpey and JCB. The company says it has not only survived in a competitive market but excelled to become a leader in its fields of operation, a fact that has only been possible using technologically advanced and efficient production at the firm’s factory.
Equipment in use includes a Bystronic 10 kW fibre laser cutting machine with automation to profile components out of mild steel sheet and seven Fanuc robotic welding cells powered by the latest Fronius pulse weld sets to fabricate the products.

Eastern Attachments director Daniel Leslie, one of four brothers who started the firm in 1996, says: “The UK is known for its strength in high added-value engineering, such as aerospace for example, but there is a perception that we cannot compete with low-wage countries in Eastern Europe and the Far East when it comes to manufacturing relatively low value, simple items.
“In 2007, most handling buckets for construction and agricultural equipment in the UK came from overseas, but today imports are becoming a rarity. Within six months of entering these sectors we had taken half the market for products we manufacture – buckets, handling grabs, forklift attachments and tipping skips – and now produce the vast majority of units sold in the UK.”
His co-director Philip Leslie sheds light on how the manufacturer has been able to succeed so dramatically: “It comes down to constant innovation. We are relentless in our pursuit of improvement, adopting a ‘what box?’ attitude to engineering challenges.
“A key part of this process was the early adoption of high-strength steels from SSAB (Swedish Steel) back in 2002,” he adds. “SSAB continue to invest in the development of new materials, which will soon see even better steels with a strength-to-weight equivalent to that of titanium and higher than aircraft aluminium.”
Attachments can be made considerably lighter using these materials, so a construction firm or farmer can lift more material to achieve higher productivity, or downsize the machine to reduce capital expenditure. A spin-off advantage of these high-strength steels is fewer impurities such as silicon, which is beneficial for achieving better edge quality when laser cutting, especially 12 mm and under (when using nitrogen rather than oxygen as the cutting gas).

Such comprehensive penetration of the attachments sector has resulted in the company growing by an average of 15% annually for the past 10 years, but 2017 has been a bumper year with an increase in turnover of over 30%. It is an enviable position but presented the Leslie brothers with the problem of how to keep pace with such a sharp upturn in demand. The situation was particularly acute in the sheet preparation department, where two high-definition CNC plasma cutters were struggling to meet the required output.
The directors had foreseen the situation and recognised three years ago that laser profiling was the way to go. They were waiting for fibre laser cutting to mature, having dismissed CO2 lasers as yesterday’s technology. When Bystronic launched the first-ever high-power 10 kW fibre laser machine at the end of 2016, which is capable of cutting up to 25 mm mild steel, they decided it was time to act.
Three other potential fibre laser machine suppliers were considered before the ByStar Fiber 3015 was purchased. The Swiss-built Bystronic machine was deemed to be preferable, due not only to what at the time was its uniquely high power, but also to its quality build and complimentary comments from other users.
A further advantage was the 30-plus service engineers employed by Bystronic UK. Eastern Attachments was already aware of the effectiveness of the supplier’s service department, having used the company’s shearing and press braking machines for several years. Prompt service to maintain high uptime of the ByStar Fiber 3015 is crucial, as it produces nearly all attachment components in the Norfolk facility, with the one remaining plasma machine cutting a small amount of material up to 40 mm thick.
The 3 x 1.5 m capacity fibre laser cutter, equipped with a ByTrans Cross for sheet storage and automated material handling to and from the machine, was installed at the beginning of summer 2017, just in time to prevent the need for a second shift on the two manually-loaded plasma cutters. The scale of the difficulty Eastern Attachments was facing can be gauged from the fact that its current factory was built to manufacture 900 units per month, yet in September this year more than 2000 units were produced.

Achieving more than double the originally planned output was only possible due to automation of the fibre laser cutter. Leslie estimates that the cell, which runs around the clock with eight hours of operator attendance, can typically produce as much in 24 hours as a manually loaded plasma machine produces in five 8-hour day shifts.
When processing mild steel 5 mm thick or less, the productivity improvement is much higher. The sheer speed of fibre laser cutting means that what would take eight hours on a plasma cutter can be achieved in one hour by the fibre laser cell. Even on thicker gauges, where laser cutting speed is broadly similar to that of a plasma machine, the Bystronic saves time through faster rapid traverse from pierce to pierce and automated loading and unloading of sheet in under one minute, compared with 20 minutes manual load/unload on a non-automated machine.
“The Bystronic has allowed us to increase cut part production dramatically in a small footprint, at the same time raising dimensional accuracy and edge quality,” says Leslie. “Fabrication is easier, the end products are improved and rework is eliminated.
“We are about to build a new factory nearby that will be four times the size of our existing facility and we’ll be moving within two years,” he continues. “It will allow us to expand even faster into new markets, grow our exports and prevent us from turning away work through lack of production capacity.”
In addition to product manufacturing, the company offers a skilled fabrication service. From a single specialist item to fully automated production runs, Eastern Attachments offers assistance with design work and technically challenging problems. Furthermore, the company can help reduce costs and improve specifications by utilising high-strength steels and advanced production techniques.
Over the years, projects have included TV and stage work, sculptures and showcase stairways, materials handling equipment, structural steelwork, stadium seating, precision automated jigs, robotic manipulators, fabrication of offshore equipment and a multitude of work for local authorities.
For further information www.bystronic.co.uk