Meccanica Plus

Precision tool grinding with NUM programming software for TN VærktøjsslibningERT

TN Værktøjsslibning, Denmark’s second-largest precision tooling company, is deploying Numroto, the renowned programming system for tool grinding from NUM across its entire production floor. The company cites highly successful long-term experience of the software, together with excellent technical support from NUM, as the key reasons for choosing to standardize on Numroto.

Founded by Torben Nielsen in 1987 – which coincidentally is the same year that Numroto was launched – TN Værktøjsslibning has grown steadily to become a leading player in the manufacture of special solid carbide tools, with an enviable reputation for the quality and precision of its products. Operating from a modern 2.000 m2 industrial facility in Bjaeverskov, some 50 km southwest of Copenhagen, the company serves the world market and currently exports about 70% of its production.

One of TN Værktøjsslibning’s prime business advantages is that it handles every aspect of manufacturing and can therefore track the movement of individual tools from initial order through to delivery. The company maintains a large stock of high quality ‘subnanograin carbide’ materials in the form of rods with internal cooling channels and solid bars, ranging in diameter from 2 to 70 mm. Using multiple advanced CNC grinding machines, TN Værktøjsslibning produces a comprehensive range of standard ‘TN’ brand high-speed end mills, step drills and form cutters, the design and dimensions of which can be tailored to meet customers’ needs for ‘exactly the right tool for the job’. The manufacturer also operates advanced in-house tool polishing and coating technology. Tools can optionally be coated both before and after polishing, to extend their service life and to help optimize chip evacuation. The company additionally offers tool regrind and recoat services. Provided that a tool is physically undamaged, it can often be returned to full service after regrinding and possibly recoating, for less than 50% of the cost of a new tool.

Every aspect of tool manufacturing at TN Værktøjsslibning is extensively automated. The main production hall is equipped with fifteen 5-axis CNC grinding centers, complemented by cylindrical grinding machines. All of these machines are controlled by Numroto software and are networked together to help simplify production management and software maintenance. Each machine has a dedicated programming station, enabling part programs to be created while grinding is taking place, and the company is also in the process of expanding its multi-user programming facility, which currently has capacity for seven users. An interesting facet of TN Værktøjsslibning’s operational structure, which is quite possibly a factor behind the company’s consistent year-on-year success, is that it deliberately has a flat hierarchy – there is no design department. Each CNC machine operator is responsible for programming, grinding the tools and fully documenting the process.

Torben Nielsen, who is still at the helm of the company nowadays as TN Værktøjsslibning’s CEO as well as its owner, said: “We try to make work as interesting and satisfying as possible for people, and over the years we have built up a dynamic team of highly qualified and committed employees. Another important point is that by standardizing on Numroto for the bulk of our CNC machining operations, we benefit immensely from our employees sharing a common pool of expertise and knowledge about state-of-the-art tool production technologies and processes. Many of our more specialist tools are only required in small batch sizes – sometimes just 2 or 3 – and yet we aim to supply these to customers within the same 9-day timeframe as our standard tools. To help meet this goal, our operators need fast, simple and unambiguous machine control facilities – which in turn demand very flexible, accurate and reliable software, with a modern user interface”.

TN Værktøjsslibning regularly enhances its machining capabilities to meet the changing tool needs of its customers. The company first started using Numroto software back in 2002, when it purchased two Deckel S20 CNC grinding machines, which have since been followed by a further ten Deckel S22 machines. The company’s current complement of Numroto-controlled CNC grinding machines comprises the twelve Deckel machines, plus a UWS SF40 cylindrical grinder and two Vollmer VGrind 340S machines. The programming and machining of special tools, which constitute the majority of TN Værktøjsslibning’s production output, is usually carried out during the day by skilled operators. Larger standard tools are processed at nighttime, using robotic part loaders and unmanned machining centers, but with a high degree of feedback such as in-process measurement and run-out compensation to ensure consistent product quality.

All tools produced by TN Værktøjsslibning undergo thorough inspection prior to shipment. The company’s quality assurance facilities include an air-conditioned, positively pressurized measuring room, equipped with a 5-axis CNC measuring machine and other precision optical measuring equipment. “Our experience with Numroto has been fantastic – said at last Nielsen -. The software is perfect for grinding both simple and highly complex tools and is extremely reliable. It is very easy to work with and the simulation is very precise. In a period of just over 21 years, there have been very few tools that we have been unable to create. Due to our very short delivery times, we rely on good support – and this has always been forthcoming from NUM”.