Prior to the launch of the Tornos SwissNano, the Swiss machine tool manufacturer enlisted a number of customers and development partners to test the machine in a working environment. One such customer, Krattiger SA has witnessed some excellent results since the installation of the machine.
After our introduction to the SwissNano in the previous issue, we wanted to gather impressions from the first customers to use the machine and the partners who collaborated in its development. An interview with Juan Arrieta, CEO, and Clovis Brosy, Technical Manager at Krattiger SA, a supplier which relies on Swiss-made machines to produce parts for the watchmaking, connectivity, micro mechanical and medical sectors.
Clovis Brosy, Technical Manager at Krattiger SA first said of the SwissNano: "When we saw it on paper, we thought that the SwissNano would the perfect machine to meet our requirements in terms of producing large numbers of watch parts. Looking back, about two months since the machine was installed, we have not been disappointed - quite the opposite in fact. We already have EvoDeco machines installed, which are a great asset in the production of complex parts, but this equipment is too high-performance for 80% of watch parts. The SwissNano is the perfect complement to our machine inventory."
At Krattiger, the new addition runs 24 hours a day, 7 days a week. It was set up to produce a barrel arbor in 20AP steel for the watchmaking sector. As Mr Brosy continues: "As we had the opportunity to collaborate with Tornos in testing the machine, we decided to make quite a complex part to see what the machine was capable of. In future, we plan to make lots of simpler parts. The results are encouraging, in terms of geometric/dimensional tolerances and surface finishes, we are right on target for our watchmaking customers."
The level of investment necessary to purchase a SwissNano machine is very competitive given the machine functionality. Krattiger CEO, Mr Juan Arrieta states: "For an equivalent investment, the SwissNano offers more options. It is equipped with 5 axes and a counter spindle mounted on three axes, and both are highly responsive powered spindles. As they are cooled, they contribute to the machine's thermal stability. We equipped the machine with an LNS Tryton, which is a very good bar feeder, but if we had an entire workshop of SwissNano machines, we would have to find a feeding solution requiring a lower level of investment."
Although the design of the SwissNano is brand new, it makes use of technological solutions that are already known. On this subject, Mr. Brosy states: "The SwissNano is not a technical master-stroke and that's a good thing! You don't always need to reinvent the wheel. The machine is well-designed; although we only received a prototype, we were quickly able to produce parts." This provided Tornos engineers with detailed and direct feedback from Krattiger AG on the machine performance.
Intuitive and simple to use
The design of the SwissNano has been praised by all the customers who have seen it. However, commenting upon the machine functionality, Mr. Brosy explains: "The machine is simple to program – it is a dual channel numerical control and is equipped with many Tornos macros, in particular for offsets and feeding. A programmer with a knowledge of ISO could master it in no time. Tool changes are also very straightforward. The machining area is accessible and we can fit the standard tools of the trade without having to modify them, as is often the case on small machines designed for watchmaking. The kinematics of the machine are well-designed, the counter spindle on three axes enables the tools to be centred with precision and end operations are simplified. With 13 tool positions (and double tool holders can be fitted), we can easily cover the range of 80% of watchmaking parts that we were aiming for."
Tornos developed the machine taking into account the requirements of the watchmaking industry. Did the test machine installed at Krattiger AG meet those requirements? "A few years ago, customers wanted to purchase very well-equipped machines to 'keep a reserve’, but today that is no longer the case. Customers want machines which are perfectly tailored to their needs. The SwissNano machine is the perfect solution for the requirements of subcontractors working with the big names in the watchmaking industry," confirms Mr. Brosy.
For two years Krattiger has diversified in four main areas of business: the connectivity business, watchmaking, micro-mechanics and the medical sector. Mr. Arrieta tells us: "Today we are consolidating our position in these four areas and are widening our network of customers. The SwissNano is a machine designed for watchmaking and will open up new markets to us, enabling us to produce a category of parts that we were previously not able to do competitively. For us, the SwissNano is a vital component in the watchmaking workshop of the future. Eventually, we plan to use our bank of EvoDeco machines to produce the 20% of complex parts, and use a new bank of SwissNano machines to complete our capacity. This machine totally won us over."
Asked about results, Mr. Brosy explains: "At present, we only have data for a couple of weeks' production, but I can confirm that the machine is very stable: swarf is not broken and we have no problems with micro-vibration." He adds: "I was surprised by the concentricity between the spindle and counter spindle; it's perfect and we've obtained excellent results straight away."