Effective cuts - cutting tools in action

Automatic Industrial Machines Limited (A.I.M) has undertaken a comprehensive review of its operations and adopted a broad range of Iscar tooling as a result. In addition to a wide selection of both manual and CNC lathes, the company boasts a number of 3, 4 and 5-axis machining centres, including an impressive collection of 28, 3-axis machining centres, with pallet changing capability and working areas varying in size from 600 mm to 6.5 m. With CADCAM technology and able to accept file information in CATIA, IGES and DXF formats, A.I.M is also a holder of ISO 9001:2000 and AS9100 quality management system certificates, as well as boasting a long list of approvals from many global aerospace companies, including Airbus UK, BAE Systems, GE, GKN Aerospace and AugustaWestland. A.I.M works with a preferred tooling supplier, West Country Tools Integration (WCTi), with this company also one of only six UK distributors to which cutting tool firm Iscar has awarded 'First Class Distributor' status. Image: Iscar cutting tools have been a key part of a rationalisation programme at A.I.M WCTi employs a team of experienced external sales engineers, skilled in the application of cutting tools, CADCAM technologies, machining methods and production strategies, with these backed up by knowledgeable, office-based personnel, while further in-depth technical assistance is also available from WCTi's suppliers. TEST AND COMPARE With the intention of rationalising A.I.M's cutting tool ordering system, substantially reducing inventory levels and ensuring the availability of the most efficient cutting tools, WCTi and Iscar UK embarked on a radical root and branch review of the Somerset-based engineering firm's entire tooling usage and process optimisation techniques. Through the course of the machining trials, Iscar's tools were judged against comparative products from competitors, taking in speed, component surface finish, tool life, unit price and time advantages. To ensure that the results of the trial were not merely theoretical, all findings were converted into objective machining costs and, where possible, calculated as savings per part. The detailed project delivered a number of positive conclusions and suggested a wide range of tool-related proposals. Now fully implemented, the recommended strategies have helped A.I.M achieve its pre-determined goals. A.I.M operations manager, Dave Kinch, explains: "As we now compete with Eastern European and Far Eastern companies for work, in addition to our traditional UK competitors, we are continuously looking for improvements and efficiencies in every aspect of our activities. As well as increased competition, we are also subject to continuous 'cost-down' pressure on many of our long-term contracts. As we regard West Country Tools Integration as not just a valued supplier, but also a valuable source of excellent technical advice, we outlined several tooling areas that we identified as having potential for improvement. WCTi suggested that, with the help of Iscar, we take a company-wide, holistic review of every aspect of our tooling." "Based on our previous excellent experience with Iscar Tools and our relationship with WCTi, we agreed that a comprehensive, company-wide review of our tooling be undertaken. Our stated targets were to reduce inventory levels, while ensuring the constant availability of, and easy access to, the required cutting tools. At the same time, we were looking to further improve our feeds and speeds, while maintaining excellent standards of surface finish. "Having implemented the vast majority of the project's proposals, we are now reaping the rewards of the time spent conducting machine trials etc. The vast majority of our cutting tools have been standardised to Iscar products, as they have demonstrated the ability to supply all of the advantages we were looking for. "In addition to fast metal removal rates, the recommended Iscar tools produce high standards of surface finish and deliver considerably extended tip life. Through the work of WCTi and Iscar, we have also been able to significantly increase our feeds and speeds within many of our operations." Part of the solution has been the installation of an e-vend tool vending system. Now in constant use and maintained daily by WCTi, this arrangement has ensured higher levels of machine tool utilisation, as the correct tool is both easy to find and always available. In addition, Iscar's range has allowed the company to rationalise its stock levels, offering further savings through reduced tooling inventory. In conclusion, Mr Kinch says: "Although we were optimistic about the outcome of this project, we have been pleasantly surprised that the efficiencies gained have exceeded all of our expectations." Elsewhere, at Wolverhampton-based Paragon Engineering & Logistics, substitution of a Horn System DD replaceable insert drill for a 'heavy duty' jobber drill has paid dividends, in terms of productivity and quality. REDUCED DRILLING TIME On a typical drilling operation in aerospace grade alloy steel, a 12 mm diameter DD drill has reduced drilling time from about 60 sec to 5 sec, but tool life has increased from around 35 holes to 350. Furthermore, use of the DD has allowed Paragon to dispense with an initial centre drilling operation. Following drilling, finish boring of the hole to final size is accomplished with a single finish-boring operation, whereas it previously required separate rough and finish boring steps. Stuart McAllister, Paragon's production engineer, comments: "Adoption of the DD drill is part of a process of continuous improvement, for the benefit of ourselves and our customers. At first sight, the Horn DD tooling is much more expensive than the HSS cobalt drill that it replaced, but the actual cost of producing each hole is lower. It's also improved conditions for the person operating the machine, as swarf is kept under control by the cutting geometry of the tip." He explains the background to this change to Horn tooling further: "Quite a lot of the material that we process is high specification aerospace grade alloy, some of which is in a fully hardened condition. This can present machining challenges, as its machineability can vary from batch to batch. What we want to do is establish reliable machining processes that can accommodate material fluctuations. From our customer's perspective, this means he gets timely turn-around, while we don't have to repeatedly tailor the process parameters for familiar jobs." The drilling application was one such job, being based on AMS 6265, a case hardening steel regularly used for manufacture of transmission components. Using the HSSco drill, the process route was initially to centre drill the component, then drill through using an 11.5 mm drill. This was followed by separate rough and finish boring operations (using the same boring bar) to bring the hole to its final size. The process worked, but there were issues regarding swarf generation, as-drilled bore finish (which necessitated the rough boring operation) and cycle time, which was around one minute per drilled hole. Tool life was not great and drill change was frequently necessary during a batch run. Stoppages for swarf clearance extended the overall batch processing time. "We came across the Horn System DD because our local Horn applications engineer, Rob Gould, was on site running a trial on another job and he suggested that we try it on this task," recalls Mr McAllister. The DD drill comprises a fluted, TiN coated body with through-tool coolant capability and a machined pocket in which is located the replaceable cutting insert. A special insertion/removal key is used to exchange the cutting insert, without the need to remove the tool from the machine. The system is currently available to drill holes from 10.0 to 20.5 mm diameter in 0.1 mm increments, while holders are available for bore depth/diameter aspect ratios of 3.5, 5 and 7. In conclusion, Mr McAllister says: "The performance of the DD is independent of the material, which is the result that we were aiming for. Eliminating the centre drilling and rough boring steps has also saved on machining and set-up time – and these are key advantages in a small batch/high variety operation like ours. "This is in line with the benefits that we've come to expect from using Horn tooling on grooving and thread cutting operations and will encourage us to use Horn tooling elsewhere." Image: Tooling performance independent of material was key to the Horn DD's success at Paragon Box item 1 Product developments in brief [] The NMT turning geometry from Walter (below), originally designed for machining titanium, now features Tiger.tec inserts to machine forged/cold-formed steel components, without producing coiled swarf. Details [] Positive Contact Sensors' PCS-100 tool, object and free space monitoring system can be used on a wide variety of machine tools and automatic processing machines. Details [] Sandvik Coromant Capto C 10 spindle connection's high bending strength couplings are designed to increase removal capacity at higher torques. A 100 mm diameter flange assists the coupling's extreme stability in heavy duty milling and turning applications. Details [] The secret of Rego Plus spindle toolholder's success lies in the toolholder's face-and-taper contact in the spindle, which means these units remain rigid in the machine spindle and provide a more stable cut, providing an increase in tool life and an overall improvement in part quality. Details (Brunner Machine Tools) [] ITC is offering the Hanita 4940 series of milling cutters for the rough machining of high tensile strength steels, titanium and similarly difficult-to-machine materials. Details [] LMT Fette believes its XChange is the first 'modular' threading tap and combines the extended tool life advantages of coated carbide with the torsional stiffness available through a high speed steel (HSS) shank. XChange can also potentially secure the productivity benefits of quick-change tools and the increased cutting speeds of carbide, with reduced risk of tool breakage. Details Box item 2 Changes at Mapal UK John Claypole will be stepping down from his role as Mapal UK's managing director at the end of the year, remaining as a director, with Wayne Whitehouse taking on the role of general manager on 1 January 2012. The changes are being made at Mr Claypole's request, because, at the age of 65 and after 31 years of selling Mapal products, including 18 successful years as Mapal UK managing director, he believes the moment has come for him to move to a position that will allow him more time to share with his wife and family, and to indulge his passion for angling. He has led the company to its currently strong position – Mapal UK's turnover and growth are breaking all records, with 2011 is firmly on track to be the most successful year in the tooling specialist's history. Mr Whitehouse has been with Mapal for more than 17 years, in which time he has worked in manufacturing, the service department, and as a sales and applications engineer. His current role is area manager for high profile accounts, a position in which he has made major contributions to the company's growth and current success. Details First published in Machinery, November 2011