I am having a problem using the G13 command on our VF-0. The same program runs fine on our Haas Mini Mill, but when transferred to the VF-0, it incorrectly calculates the cutter comp. The tool radius was registered in T03 tool diameter offset at .25, just like in the Mini Mill. Here is the code using a .25 endmill: G13 I.5 D03 F11. This should produce a 1.0″ diameter hole, but since it ignored the cutter comp value, it went way undersize.

Tim

Dear Tim,

The problem is a difference in the value for Setting 40 (TOOL OFFSET MEASURE). The Mini Mill is set to DIAMETER, while the VF-0 is set to RADIUS. Please change Setting 40 on the VF-0 to DIAMETER to match the Mini Mill. This setting selects how tool size is specified for cutter compensation. It can be set to RADIUS or DIAMETER. The label on the offsets page should reflect how the offsets need to be entered.

Sincerely, Answer Man

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In 21st century warfare, developed nations and their armed forces have come to rely on technology in the same way that they previously relied on strength of numbers. The battle is often won in the laboratory, long before aircraft take to the skies, ships sail or tanks roll. If they’re well equipped, fewer men and women are needed than ever before to defeat a less technology-empowered enemy, and win a confrontation.

But for all the devastating effectiveness of modern weapons, the greatest advantage an army can have still remains the element of surprise. To protect and preserve that advantage, forces use technology in the shape of electronic counter-measure (ECM) devices.

On the outskirts of Cape Town, South Africa, Plexsa Manufacturing is using advanced manufacturing technology to build components for the next-generation of ECM systems, usurping some of the biggest names in ECM systems in the process.

Plexsa Manufacturing

Plexsa Manufacturing was started just 4-years ago, and still only has 8 full-time employees, but the company’s ability to design and build small, light-weight and reliable microwave filters marks it out as a name to know for defence OEM’s around the world.

A microwave filter is a radio device that works at extra, super-high-frequencies to block certain transmissions and to let others through. When installed in the on-board defence systems of military ships, aircraft and tanks, they form a vital part of the vehicle’s electronic counter-measure capability, helping to protect it from detection, identification and hostile fire.

There’s nothing new about microwave filters per se, but through innovative design and manufacturing techniques, Plexsa is setting new standards in performance and reliability.

“For years, Herman talked about this idea he had for designing and manufacturing a microwave filter,” says co-director Izelda Swanepoel, referring to her husband’s obsession: the precursor to Plexsa. “Sometimes, that’s all he’d talk about. About eight years after we were married, I started to worry. I thought to myself, have I married a very clever guy, or a very crazy guy?”

All this time, Herman was quietly developing a piece of software that would allow him to design and build an ECM device that would be better than anything available – anywhere.

Before joining the company, Izelda was a music teacher, with just a passing interest in business.

“I started working at the company because I thought if we made it a success, I could get what I wanted: a music studio.”

What she didn’t realise at the time was that she had a hidden talent for management, and a latent fascination with business. Nor did she realise just how revolutionary Herman’s design would prove to be.

Thanks to his groundbreaking software, the Plexsa microwave filter is smaller, easier to manufacture and with a better specification and a lower cost than other microwave filters. The result is an inherently accurate device, with no need for the tuning screws found on competitor’s products.

“We’re a very software intense company,” he says, “and it’s the software that allows us to design and manufacture filters which work first time, without the need for tuning.

“However, we’re also mechanical engineers, and we go to a great deal of trouble to engineer parts to fit the allotted space. In fact, housing the product and making it fit can be a much more demanding job than designing the PCB,” he adds.

The customer specifies the frequencies the filter has to work at and its physical dimensions. Plexsa then designs the device using two CAD systems: one for the electronics and a separate system for the mechanics. Before anything is made, the product is tested using a virtual prototype.

“If it works on the computer, we know it’ll work in reality,” Herman says.

Manufacturing Technology

When a company’s competitive advantage relies so heavily on manufacturing processes, it’s no surprise to discover that Plexsa has a tendency to bring operations in-house, rather than to outsource. In fact, the only thing it doesn’t do is paint and label the finished product. It designs the device, makes and tests the prototypes, electroplates the aluminium housing, precision etches its own PCB’s to an accuracy of 10 microns and assembles and tests the final product for electronic interference, vibration and thermal shock.

Plexsa also has its own rail-camera for producing the 1:1 negatives of the PCB layout. These negatives are contact printed onto copper plate coated with a light-sensitive material. The outline of the circuitry is then mechanically etched in the copper to produce the PCB.

Since it invested in two Haas CNC Super Mini Mill vertical machining centres, Plexsa also performs its own machining operations, mostly on the aluminium housing components.

“We were tired of relying on external subcontractors,” says Herman, “and we wanted to have complete control of the manufacturing process. Hence, the two Haas machines.”

The Haas Super Mini Mill is a high-speed variant of the standard Mini Mill, built by U.S.-based Haas Automation Inc. The concept on which the compact Mini Mill is based is a simple but effective one, and appeals to Herman’s fixation with maximizing the use of available space: a small-scale machine for all of those small-scale jobs that would otherwise tie-up a much larger machine. The Super Mini Mill expands on that concept by offering a 10 000-rpm spindle and 30 m/min rapids as standard.

“We didn’t want a production capability,” he states  – the quantities the company is machining tend to be quite small  – “but we did want very good accuracy and dependable repeatability. Plus, of course, the service and support had to be good.”

The company bought the first of the two Haas machines in 2003, from Johannesburg-based Haas CNC Services. But, before taking the plunge, Herman thought hard about his requirements and the lack of in-house CNC experience at the company.

“We have limited space,” he says, “so the very first criterion was that the machine had to be small. The Super Mini-Mill was exactly the right size.”

It also had to be easy to learn and easy to use. Characteristics the two machine operators – brothers Hilliat and Christiaan Solomons – will attest to. Neither had machine tool experience before joining the company, and both men have been trained in-house.

“The machines and the CNC are very easy to learn,” says Herman. “Even with no previous experience, Hilliat and Christiaan have become extremely competent in a short period of time.”

The Haas machines currently run for approximately 50% of the working week, producing batches of around 100 units, typically in 6061 aluminium.

“We use 6061 because it’s very easy to machine, says Herman. “We mill the housing from flat bar, and drill and tap holes as small as 1.6 mm diameter.”

Nowhere to hide

Because of their personal commitment to Plexsa, the husband and wife team don’t currently own a house. In fact, the only property they do own is the new factory they moved into a few months before my visit. Plus, of course, the two Haas Super Mini-Mills.

“So far, we’ve built the company by reinvesting profits,” says Izelda. “We spoke to external investors and we decided we wouldn’t go that route. We want to maintain control, and we want to grow at a manageable rate.”

Herman points out that the couple’s prudence means that if business increased significantly, they probably wouldn’t be able to cope.

“At the moment, we have one main customer who accounts for most of our production,” he says. “Before we go actively seeking new customers, we want to have our in-house production capability working as smoothly as possible. I’d rather take a little longer, than rush and make a sub-standard product.”

Judging by Plexsa’s success so far, Herman and Izelda may have less time than they think. Once word gets out, not even electronic countermeasures will protect them from the inevitable attention of the world’s defence contractors.

The Business of Quality

Tesa Technology was formed in 1941, following the closure of a telephone components factory. The managers of the defunct company decided to explore the potential market for high-precision instruments for dimensional inspection and measurement. The rest, as they say, is history.

The subsequent 65 years have been a catalogue of pioneering “firsts.” Shortly after formation, Tesa Technology enjoyed commercial success with its first micrometer. One of its subsequent products, the Imicro internal bore micrometer, was revolutionary in its use of a “three-line” contact system, a design admired and emulated ever since.

In the 1960s, Tesa introduced electronics into its metrology instruments. Later the same decade, the company relocated to larger premises and became part of the U.S.-based Brown & Sharpe group, a move that allowed it to benefit from a synergy that only a leading global group can offer (since 2002, Brown & Sharpe has been incorporated into the Hexagon Metrology group). In the 1980s, Tesa opened its first overseas subsidiaries (in the UK and Japan), and began to grow by acquisition, firstly by purchasing its main Swiss competitor, Pierre Roch.

Although the industrial landscape has suffered many a shake-up over the past decade, come what may, Tesa has managed to preserve its culture of independence. By grasping opportunities that have come its way, the company has also been able to extend its range of instruments, and build a reputation for quality, precision, and non-stop innovation.

CNC Machine Tool Investment

Over the years, Tesa Manufacturing Manager Francois Pollicino has witnessed many changes. He learned his trade with the company, and has been an employee for more than 30 years.

“Tesa has never stopped investing in its knowledge and experience of manufacturing technologies to safeguard its competitiveness,” he says. “This is important in a business environment where change and competition are a way of life, and always fierce.”

To ensure the long-term viability of continuing to manufacture in Switzerland, Tesa has had to master the most advanced processes and techniques.

Its latest investment is in four, U.S.-built, high-speed Haas CNC vertical machining centres: two VF-4SSs and two VF-2SSs, purchased during 2005.

“We examined the CNC machine tool market very carefully, and concluded that Haas offered the best combination of price and quality,” says Pollicino. “Haas also offered excellent delivery and installation time. The machines arrived on a Monday, and were ready to work by the following morning. It then took just one further day to train our operators.”

The Haas VF-2SS and VF-4SS are high-performance vertical machining centres that come standard with an innovative 12,000-rpm inline direct-drive spindle, an ultra-fast tool changer, and 36 m/min rapids.

Service and Support

According to Pollicino, service was another factor in the decision to buy Haas.

“Typically,” he says, “in Switzerland, service costs are high. However, the local Haas Factory Outlet (a division of the world-renowned tooling manufacturer URMA), set a fixed price for service, so the running costs were known prior to acquisition.”

Pollicino also claims that Tesa selected the high-speed Haas machines to provide a superior surface finish on the aluminum, steel, and brass components used for its range of measuring devices, which are sold all over the world (interestingly, only 10 percent of sales go to Swiss customers). Previously, the company had used various external subcontract machinists, but they wanted to assert more control over component quality, delivery, and cost by bringing the work in-house.

These days, almost all Tesa parts are designed in-house using Pro-Engineer and Esprit, and files are sent directly to the company’s machines.

Since installation, the Haas machines have been hard at work manufacturing around 100 different parts, many for a number of Tesa’s recently introduced products, including the TesaStar range of probe heads, the Tesa Visio 300 non-contact bench-top vision machine, and the Tesa Micro-Hite 3D coordinate measuring machine, which offers repeatability down to 0.0025 mm.

“Working with such small margins of error demands high-precision machining,” says Pollicino. “Typical tolerances on the Haas machines are ±0.02 mm, although two are used for roughing operations and two for finishing, arranged in manufacturing cells (one operator for two machines). However, such precision cannot be allowed to compromise speed, as batch sizes are typically 100 to 300 off. To this end, the capability of the Haas machines allows us to perform operations at spindle speeds of 12,000 rpm to achieve very high surface cutting speeds. This capability results in surface finishes in the realm of N5-N8.”

The performance of the Haas high-speed machines has allowed Tesa to dramatically reduce machining costs.

“The Haas machines are located alongside other brand machining centres of far higher price,” concludes Pollicino, “where they perform many of the same or similar operations. They operate across two shifts, for a total of 16 hours a day, and rarely – if ever – miss a beat.”

Story and photos by Matt Bailey

How do I change my active work offset? The default seems to be G54. I am running the whole length of the table, but keep getting X over travel alarms. I am trying to input the correct values for my G58 work offsets. Whenever I put G58 into MDI and press Start, it stays at G54 on my Positions page and Current Commands page.

Kenneth

Dear Kenneth,

Please change Setting 56 (M30 RESTORE DEFAULT G CODES) to OFF. Then go into MDI and input G58 and press Cycle Start. Your G58 will remain active until another work coordinate system is selected. Here is a detailed description of Setting 56:

Setting 56 – M30 RESTORE DEFAULT G CODES

This is an ON/OFF setting. When it is OFF, no change to the modal G codes occurs at the end of a main program that ends with an M30. When it is ON, an M30 will reset all the modal G code groups to their defaults. If this setting is ON, pressing RESET will also reset defaults. Initially set to OFF from the factory.

Sincerely, Answer Man

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By Matt Bailey

Based at Ludvika, 150 km northwest of Stockholm, Sweden, in a region that once boasted more than 20 busy iron, copper, lead and zinc mines, Essverk AB builds bespoke excavation equipment used by road and tunnel construction companies.

Up to the late 1970s, Essverk built mining equipment – until the geology and hard rock that provided the nation with seemingly inexhaustible mineral wealth conspired against it, and forced it out of the global ore markets. The mining industry went in search of lower costs and softer rocks. To survive, Essverk turned its hand to developing excavator equipment. Today, the company designs many of its products as bespoke solutions to its customers’ very specific demands.

Natural Resources

During the Pleistocene epoch, huge glaciers inched across the area we know today as Scandinavia, depressing the rock beneath and leaving thousands of surface lakes in their wake. In the North West – along its frontier with Norway – Sweden is bounded by the Kjölen Mountains. East of the mountain range, the topography descends slowly all the way south to the Gulf of Bothnia, where icy rivers flow along the faulted lowlands, crashing over precipitous waterfalls and into ancient lakes like the Vänern, one of the largest in Europe.

The country lies on a tectonic plate referred to by geologists as The Baltic Shield, made from the oldest rocks in the European continent, and up to 300 km thick. Deep inside this cold geological heart of crystalline and metamorphic structures lies an estimated 15% of the world’s uranium deposits.

Beneath the silt left by the ice sheets, the going gets tough, and most of the roads and tunnels built in Scandinavia require extensive excavation work. Construction firms in the region prefer to own their vehicles rather than rent them, so to keep costs down, many demand excavator attachments that enable a single vehicle to complete multiple tasks.

Multi-Tool

Essverk AB is best known for its Multivip ‘Rototilt’ device, an innovative piece of equipment that transforms all kinds of excavator and loader operations. With its ability to dig, tilt and rotate in a single movement, it converts excavators from a simple digger into a versatile platform for a wide range of attachments. The Multivip Rototilt enables work from a static position with great flexibly, while tilting in two directions simultaneously, eliminating the need to constantly reposition the machine.

Demand for the Rototilt is high, so much so that Essverk recently had to re-think and reorganise its machining capacity, as Bengt Ericsson, the company’s technical systems specialist, explains:

“A few years ago, we had our own machining capability, but the industry trend at the time was moving toward outsourcing and its apparent cost advantages,” he says. “So we adopted the same strategy. However, in the past few years, Swedish subcontract machining companies have become extremely busy, and the lead-times quoted have grown longer. In turn, our own lead-time had started to extend; a situation that was unacceptable.”

To bring machining back in-house, Essverk began searching for a large horizontal machining centre well suited to manufacturing small batches of prismatic parts having various drilled and pocketed features. Cost, size, reliability and support were all criteria thrown into the company’s evaluation of options. The eventual choice was an EC-1600 CNC horizontal machining centre from Haas Automation.

“The specification, together with its performance and the price, represented the best business decision,” states Mr. Ericsson. “It was also available on a short lead-time, whereas other suppliers were quoting months.”

Installed in late 2007 by Haas Factory Outlet (HFO) Edströms Maskin, a company with 60 years’ experience supplying manufacturers in the region, the Haas EC-1600 has already been put to work machining Rototilt components destined largely for Norwegian customer Nanset Standard AS, a distributor for Hitachi Construction Machinery. Parts are designed by Essverk to Nanset specification.

Rototilt parts machined on the EC-1600 include housings (weighing up to 330 lb), lower bodies, upper bodies and all internal components. In total, 55 different Rototilt parts are manufactured using the new Haas machining centre, making the most of the machine’s 30-hp, 50-taper spindle and its maximum speed of 6,000 rpm. There are three different sizes of Rototilt model, and components are typically manufactured in sets, using fixtures that are machined in-house (also using the EC-1600). Each fixture presents two, three or four different parts to the cutting tool, ensuring maximum use of the machine’s 64″ x 36″ table.

Cycle times vary from 5 minutes for the smallest and simplest part, to 2 hours for the largest housing. All components are manufactured from various grades of engineering steel, and tolerances are surprisingly tight – ±0.0004″ in some instances – particularly for parts with bearing surfaces.

Despite the high demands, the Haas EC-1600 has coped admirably, as Mr. Ericsson confirms: “Since installation, we’ve had no rejects whatsoever,” he says. “Off-line programming is straightforward using intuitive commands, and both of our trained operators enjoy using the machine.”

The company has since ordered a Haas SL-30 CNC lathe, which sits alongside the EC-1600 at the company’s Ludvika factory.

“The new Haas machines have helped reduce our lead-times and get our production back on track,” says Mr Ericsson. “At present, the EC-1600 is running eight hours a day, but this will be increased shortly, once we have finished manufacturing a range of welded fixtures that will help reduce set-up time. We also intend to undertake subcontract machining for local companies. Eventually, the machines will be running sixteen hours a day.”

Given the country’s vast reserves, it was once inconceivable that Sweden’s mines would ever close. But eventually they did, as cheaper, more accessible ore became available to the world’s metal smelters. Companies supplying the country’s mining industry had to adapt to survive. Many didn’t.

As well as uranium, archeologists believe that the country’s ancient rocks also hide the world’s largest reserves of gold and diamond. Mining its own reserves of talent and ingenuity, at least one tenacious equipment supplier will be around for Sweden’s next mining boom.

Indiana-based 80/20 Inc. builds and sells what company founder Don Wood calls The Industrial Erector Set: a modular aluminum framing system that can be configured into such things as a simple table frame, a machine guard, a display case – or whatever else a customer can imagine. Wood’s recipe for success includes judicious application of Stephen Covey’s 7 Habits of Highly Effective People to build his business, and investment in Haas CNC machines to boost productivity.

We are considering buying a 40-taper VF-3 with a two-speed gearbox. Can you tell me if it is able to perform thread milling? I was told that you needed a CAM system to do this, is this true?

Scott

Dear Scott,

All Haas mills have thread milling capabilities. It is not necessary to use a CAM system; there are many methods that can be used to generate the G-code required to thread-mill. To calculate the tool path, you need the size, pitch, and length of the thread. You will also need the feedrate, rpm, radial depth-of-cut, and diameter of the thread mill. With these parameters, you can use a program provided by the thread mill supplier, an online thread milling program, or you can write out the code longhand. Example: 1.5×8 tpi thread, depth of .6″ using 2-flute 1/2″ thread mill at 1910 rpm and 11.5 ipm feedrate. The center of the thread is at G54 X0. Y0. The thread is cut from the bottom up, because it is right-handed; this is also the preferred direction, because of chip control issues.

EXAMPLE

Sincerely, Answer Man

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It’s estimated that at some point in their lives four out of five adults will experience back pain, most often due to wear and tear, but occasionally as the result of neglect or an accident. Top of the back injury list is what’s commonly referred to as a “slipped” or “ruptured” disc – more correctly known as a herniated disc.

In the least severe cases, remedying a herniated disc involves nothing more invasive than rest and cold compresses. For more serious cases – those in which a disk fragment actually lodges in the spinal canal causing a loss of function – a surgical procedure involving the removal of the damaged item, the insertion of a structural cage (to maintain support of the spinal column) and fusing of the vertebrae may be necessary. It’s an operation that’s often performed reluctantly. After all, fusing a structure that depends upon its inherent flexibility to be effective is less than ideal.

Until now, fusion has offered most patients the best long-term “cure.” But, thanks to the innovations of Irene, Gauteng-based bio-medical engineering group Southern Medical, the need for vertebrae fusions may soon be a thing of the past.

Established in 1987, the Southern Medical group of companies consists of five entities: Southern Implants; Southern Allograft; Southern Ear, Nose and Throat (ENT); Southern Cryoscience; and Glycar. Group co-founder and partner Malan De Villiers explains how the company’s implant expertise evolved.

“Originally, Southern Medical was set up to develop a locally made heart valve,” he says. “However, we got as far as animal trials when we realised that the development process was just going to take too long. So instead, we changed tack and took on an agency to distribute dental implants.”

The company’s unplanned detour eventually resulted in it manufacturing its own range of dental implants – a natural evolution, given De Villiers Ph.D. in bio-medical engineering. A few years later, Southern Medical expanded again, when it developed its own spinal fusion system. “A run-of-the-mill product for companies in the spine sector,” claims De Villiers.

The company also started making vertebral cages, know as anterior inter-body fusion devices. These are small polymer structures that are inserted into the spinal disc space to maintain the correct angle and height of space, so that the bone can fuse around it.

When an individual vertebra is fused, the adjacent levels of vertebrae have to compensate for the loss of articulation. The increased stress can have a knock-on effect. According to De Villiers, many vertebral fusion patients have to return later in life to have additional surgery.

“Medical publications talk about the success rate of a fusion,” he says. “But what they’re actually talking about is whether they achieved a satisfactory fusion, not whether they achieved patient satisfaction.”

De Villiers and his team felt there was a need for an alternative, a way in which the damaged disc could be removed or replaced without a loss of mobility. The company began looking at creating an artificial disc.

Its efforts resulted in an implant that provides the support and movement characteristics of a healthy vertebral disc, and avoids the need for fusion.

The unit’s simple structure comprises two Grade 5 titanium end plates sandwiching a low-friction polyurethane meniscus. Grade 5 titanium is characterised by its high osteoconductivity, and is ideally suited to serve as osseointegrated bearing plates. It has high corrosion resistance, and it’s also MRI compatible, for good imaging.

Important though the choice of material was for the new implant, achieving a suitably high level of quality and surface finish was an equally high priority. To pass stringent FDA regulations means that the implant has to reach exceptional manufacturing standards. Although the company already had a well-equipped machine shop, a new set of tools was most definitely in order.

The Sharpest Tool

Tucked away on the company’s 45,000-square-foot campus is a small but busy CNC workshop run by precision engineer Jan Hugo.

“When we decided to look for new CNC machines for the on-site workshop, I found out what was on offer and made a list based on cost and performance,” he says.

Hugo was well qualified for the task. Before joining Southern Medical, he worked for a precision engineering company, so he already had a good idea of what was available and what Southern Medical needed. Gathering information from various sources, Hugo contacted a local CNC machine tool supplier he’d known at his previous company.

“Johan Pieterse used to supply and service the CNC machines in my last job,” he says. “When I called him I discovered that his company had been appointed as the Haas distributor for South Africa.”

In fact, since its appointment, Pieterse’s company – Bredell, Johannesburg-based Haas CNC Services S.A. – has quickly established a strong foothold in the high-value end of the South African CNC market. The extensive range of Haas machines – more than 65,000 in operation around the world – speaks for itself. Pieterse’s reputation as a seasoned CNC expert does the rest.

“The Haas machines already offered the value and accuracy we were looking for,” says Hugo. “Knowing Johan and his wealth of experience tipped the balance for us. We felt very comfortable about buying from him.”

The company invested in two Haas CNC Mini Mills – one with a 4th-axis rotary table – as well as an SL-10 CNC turning centre.

“Some of our products have quite complicated surfaces, so the programs can be large,” Hugo adds. “The Haas 4th axis allows us to carry out this complex machining without the need for fixings or workholding devices. It makes the whole process quicker and much easier.”

To be effective, it’s essential that the surfaces of a surgical implant are flawless and true. No amount of polishing will make a poorly finished component useable.

“With the Haas machines we’re getting very close to the final surface finish we need,” says De Villiers. “When we do polish, we know that all the surfaces are going to be congruent. To comply with our quality standards, we check every single part we make, but we don’t really need to.”

Hugo adds: “At times we’ve had to sub-contract some of our milling work. The finish we were getting from our supplier wasn’t as good as the finish we get from the Haas machines. I’ll be honest, when we bought the Haas machines we weren’t expecting to get such good surface finishes.”

As the company pushes forward with the development and certification of the implant, the Haas machines are running an average of 16 hours a day, 6 days a week. Having them on-site means that communications between the designers and the manufacturers are facilitated; changes and revisions in the design can be made quickly and easily. Productivity considerations aside, De Villiers sees other advantages to having a shop full of new machines close-to-hand.

“Having the Haas machines here also allows us to show customers exactly what we do,” he says. “We often have surgeons who come here and want to see the whole process. On a tour of the campus, we can take them around the quality control facility, administration, packaging, etc., and if they want to see how the product is manufactured, we can show them the Haas machines in action, instead of having to drive them 30 miles out to the main factory.”

The Big Question

The design of the Southern Medical disc implant allows for translation of the meniscus during articulation, accurately mimicking the natural movement of the spine. The slightly posterior location of the implant’s centre of rotation is similar to the mechanics of lumbar discs, and allows natural arcs of rotation and normal movements.

“Our aim is to simulate the articulation of the spine as closely as possible,” says De Villiers. “The further one gets away from that natural movement, the worse the overall result will be.”

The implant’s unique retention device – centrally located in the meniscus – allows a load-bearing surface up to 50% greater than other arthroplasty devices, the company claims. To reduce wear, the articulating surfaces of the end plates are provided with a titanium nitride (TiN) finish.

The company’s accelerated testing predicts less than 2% wear in the meniscus over an 18-year period. But perhaps the most significant improvement over older technology is the patient’s recovery rate.

“The surgical technique for placing the implant is compatible with a micro-invasive approach,” says De Villiers. “We’ve also developed patented instrumentation to facilitate placement.”

Typically, the patient is able to walk around a day after the operation, and between two and four days later, some patients are discharged from the hospital.

“In the past, the patient would be in hospital for 5 or 6 days, and would then have to wear a brace for a month or 6 weeks,” claims De Villiers.

Overall, both the direct and indirect costs of a disc implant operation are less than a spinal fusion. The operation is quicker, the time in the hospital is shorter, and the patient gets back to work sooner and is less likely to need revision surgery at a later date.

For spinal disc surgery in general, the $64,000 question is whether disc implants will become as common as hip and knee joint implants are already. The signs are good. Even the most conservative official sources estimate that at least 30% of future cases traditionally requiring spinal fusion will be treated with replacement discs. For Southern Medical, the early-mover advantage it has secured by its astute application of design and manufacturing technology will help ensure continued success when that day comes.

Sidebar

The Vertebral Disc

The vertebral disc is a complex and vital component in the human spine. It’s first function is as a shock absorber, but it also allows articulation of the vertebrae and permits the spine to curve and flex as we sit, stand, walk and otherwise go about our normal, everyday business.

The disc itself is composed of a tough outer ring and a soft inner core, a configuration not dissimilar, say the experts, to that of a jelly doughnut! In the event of a spinal shock, a disc can rupture and force part of its nucleus (a gel-like substance) into the spinal canal, putting pressure on the nerves. To those unfortunate enough to experience the condition, it doesn’t matter what caused it or how you refer to it, it’s painful, and if left untreated can have long-term debilitating effects.