High precision

Citation

(2007), "High precision", Aircraft Engineering and Aerospace Technology, Vol. 79 No. 4. https://doi.org/10.1108/aeat.2007.12779dab.003

High precision

High precision

When world-class motorcycle racer, Martin Gopp came to recognize that his days as a competitor rider, inevitably, would be numbered, it was already a foregone conclusion that he would return for his livelihood to that of a too/maker for which he was originally trained and well-qualified. What better than to apply those skills in the world of racing in which he had been passionately involved for so long. It proved to be a brilliant and far-sighted move for it culminated in the Kawasaki Team, with Martin Gopp as Technical Manager, winning the Supersport 600 World Championship in 2001 (Figure 17).

Figure 17 Martin Gopp

When Kawasaki decided, however, to move its team base back to Japan, Martin opted to set-up on his own with work assured from them in his home town, Feldkirch, situated in one of Europe's most beautiful areas, the western tip of Austria, within sight of the majestic Alps. The outcome has been an outstanding example of inspirational entrepreneurship and extraordinary technological achievement not only for the good of the sport, but also in numerous other areas of high-precision engineering.

Martin Gopp, using his engineering skills to fine-tune the racing bikes he had as an international competitor raced, and to further enhance them through product development, established his own company, Martin Gopp Tuning, his guiding objective being “precision, precision, precision”.

To succeed in GP1 and Superbike racing at world-class level, the technical backup for such work as machining cylinder heads, carbon fibre moulds, chassis parts, steering parts for Formula 1, etc. must be provided by engineers who are not only dedicated to the sport but to whom the generally accepted concept of high levels of accuracy and precision are not enough. It is to this small band of perfectionists that Martin Gopp belongs.

Prototype manufacturing

Now suitably equipped with advanced machining equipment installed in temperature and humidity-controlled premises, the company specializes in prototype manufacturing for an ever- increasing raft of high-profile companies seeking his help with their own product development.

Enter Blum-Novotest

Determined to further provide customers with the highest standards of technology available on the planet, Martin Gopp decided to establish a very close working relationship with leading- edge, international measurement and inspection specialists, Blum-Novotest, whose headquarters are in southern Germany, with subsidiary companies around the world. What attracted him in particular was Blum's laser tool measuring technology.

Starting point

The Blum laser system provides a measuring accuracy of less than 5m for the length, radii and wear of all the tools used and, says Martin Gopp, is the starting point for virtually each and every machining task.

Anybody familiar with the importance of the swirl patterns within the combustion chamber/cylinder head of an internal combustion engine will know that constant experiments with and improvements to such components are sought by top racing teams.

Apart from the ability to provide a rapid response while working under intense pressure, the manufacture of such complex shapes calls for an almost unbelievable level of geometrical intricacy and for it to be carried out with great precision.

The four-cylinder light-alloy head pictured, for example, took about 40h to fully machine and even the 38-tool capacity of the vertical machining centre employed could not hold all the different tools used in the operation.

Martin Gopp Tuning meets such special requirements through the aid of a specially-mounted Blum LaserControl NT Micro Compact System with 0.5 m repeatability, on a Heidenhain iTNC 530 CMC- controlled, Hermle C40U five-axis machining centre (Figure 18).

Figure 18 The Blum LaserControl NT with calibration pin in action (for temperature compensation) at Martin Gopp Tuning

The nature of Gopp's work has resulted in an exotic collection of both standard and valuable special purpose and form tools that are all measured and then checked for wear and breakage using the Blum laser system with the data stored within the Blum-supplied computer program.

In-process measuring

Held in Martin Gopp's extensive tool racks, the tools range from drills as small as 0.3mm diameter right up to the nine-insert tool illustrated that is 125mm diameter and is used for cutting large, thick, tooling plates to size. A tool like this is a good example of the benefit of the Blum system's ability to measure tools whilst actually rotating in the spindle at working speeds (Figure 19).

Figure 19 Section of tool rack highlighting the range of tools measured using the Blum LaserControl NT systems at Martin Gopp Tuning

Blum's patented NT technology eliminates the effect of coolant in the measuring operation, using a microprocessor integrated into the machine control only when the effective radius (the longest cutting edge) completely leaves the beam. There is no interruption of the beam through an entire revolution of the tool. This overcomes the problem posed when the beam passes through the gap left by two cutting edges as they rotate, which might otherwise cause a measuring error.

Measuring to 0.005mm

Tool lengths at Martin Gopp Tuning also show unusually wide variations, the longest being deep boring tools on cylinder heads to produce the internal camshaft bore. Martin Gopp proudly recounts that, when used from opposite ends of the component, they meet showing an axial displacement of less than 0.005mm.

Demanding team spirit

To some equipment suppliers Martin Gopp might be thought of as over- demanding in his quest to reduce measuring errors to near zero, but Blum is happy to cooperate with him. As Blum's Lothar Halder points out, “Martin Gopp looks for extreme accuracy and his pioneering work in this field is a two-way street. He is an extremely capable engineer and helping him to solve his problems provides us with valuable feed-back that we can put to good use in the future”.

An example of this strong cooperation has been the way all parties have worked together on overcoming the influence of temperature differences within a machining process that can significantly affect, or even exceed, the specified work-piece tolerances.

A development of this work, using the Blum laser system to measure and calibrate tools in combination with active Hermie sensors in the machine tool, has enabled the high accuracy of finished work to be maintained by automatically compensating for the natural temperature drift of machine axis and spindle. Martin Gopp declares himself highly delighted with the results.

Easier access for ultimate in accuracy

Most Blum users are, inevitably, concerned with productivity, albeit allied with reliability, precision and ease-of-use. So they are naturally attracted by the many advantages the laser system offers. Martin Gopp Tuning, however, is rarely called upon to produce more than one or two of any one component before making changes but, nonetheless, always needs to keep the machine tool working hard if it is to pay its way. Hence, most machines of this type have the laser unit sited at the rear, as close to the automatic tool changer as possible to minimize time lost in positioning the spindle for tool measuring checks.

Martin Gopp, however, is always looking for that extra minute improvement in accuracy and so he likes to physically clean each tool when in position before checking. Therefore, he made the unusual request that Blum reposition the unit on to the front of the trunnion-mounted table in order to afford easier access for this purpose.

Expansion into new areas of business

A typical example of how Gopp's expertise from the world of GP motorcycle racing can be applied to other, totally unexpected applications, is the wonderfully sculpted Pelton bucket style component produced for a water turbine manufacturer.

Clearly there is a similarity of thought and design between the machining of this and meeting the swirl pattern demands of the previously mentioned cylinder head. The tool positioning accuracies secured through the use of the Blum system enables not only a superb surface finish to be achieved, but brings with it subsequent efficiency gains in the energy supplied and thus a superior end-product.

Confident justification

Undoubtedly, the majority of Blum laser technology users are looking for productivity improvements and time- saving as major components of their return on the investment justification calculations.

Martin Gopp, however, makes the point that the system has only to avoid a single severe collision situation to have paid for itself. Like many experienced machinists, he knows that it is a fact of life that tool mix-ups can occur, but he says that with the Blum laser system installed, he now works with a far higher level of confidence than was previously possible.

On a more mundane but very practical level, he records the details of each tool on a magnetic strip that stays attached to the tool while in the rack. When loading the tool carousel for a job, the strip is then removed from the tool and placed on the appropriate tool position space marked out on the machine guard in order to provide a complete reference as to which tool is in each position in the carousel.

New touch-probe system

Speaking of his satisfaction with the high level of positive support he has received from Blum Novotest, Martin Gopp says that he is now looking to add a touch-probe system from the same supplier to his armoury. He believes that this, with its superior measuring accuracy and high measuring speed, will be invaluable to his operation because it will enable him to carry out in-process measurements of parts. He knows that, as a company specializing in prototype part manufacture, such a facility will further enhance his status as a top-class supplier.

Details available from: Blum Novotest Ltd Tel: +44 (0)1543 257111; Fax: +44 (0) 1543 251746; E-mail: david@blum-novotest.co.uk; web site: www.blum-novotest.com; Martin Gopp Tuning. Tel: +43 5522 37638-12; Fax: +43 5522 37638-19; E-mail: martingopp@aon.at