Collet knowledge

The chances are that every day we pick up or use something that has been manufactured making use of a Hardinge collet. Hardinge workholding products grip parts that touch lives around the world, at home, at work, or on the road and involving almost every industry imaginable," claims Hardinge Inc director of sales for workholding Mike Levanduski. It's a bold claim, but Mr Levanduski has worked for the largest collet manufacturing organisation in the world for over 35 years, while the company itself has a pedigree dating back 130 years, to pioneering days in small workshops in Chicago when the company started manufacturing the earliest 5C lathe chucks. Experience runs deep at Hardinge, and even Mr Levanduski's length of service and knowledge takes second place to Dave Myers, the collet division's chief designer. If there were such a title, he would easily qualify as 'a collet legend in his lifetime', being renowned for his photographic memory and recall of the designs and features of special and bespoke collets he and the team have designed during his lengthy Hardinge career. IMPARTIAL APPROACH In Elmira, New York state, Myers and his team comprise a talented group of 15 workholding engineers, with over 300 years of combined engineering experience. These hands and minds have a mission to improve accuracies, reduce set-up times, reduce costs, add flexibility to a machine, develop new workholding concepts and solve gripping problems. And they are keen to stress they do it impartially; there being no differentiation between a customer with a Hardinge machine and any other make. Myers estimates they have designed and manufactured over 200,000 special collets and mandrels – that is on top of some 40,000 products in the 'standard' Hardinge catalogue. "There isn't a machine shop worldwide that can say they've never had a problem gripping a part," assures Mr Levanduski. "It's an odd shape, it's slipping, it's too delicate, it's getting scratched, there is not enough gripping surface or it's threaded." The list of workholding challenges goes on and on. Yet, before sinking hours into experimenting and creating a pile of scrap metal, the logical, fail-safe move should be to put these frustrating gripping problems in the hands of experience, where the end result will be safe, accurate and reliable. "There is a lot of expertise in and about Hardinge, but collet expertise revolves around manufacturing, mechanical, applications, programming, electrical and design engineering," he adds. "Hardinge and its engineers hold several active patents for new and improved workholding products – special or otherwise – which are multi-purpose and can be manufactured for any machine tool and workholding problem. No job is too small or too big, whether you're just starting up a subcontracting shop and in need of help or you're a senior engineer from Boeing – it's all the same to us." Specials play a big role in the Hardinge offer and, remarkably, most of the global inquiries for specials end up not only being designed in Elmira, but also manufactured there, too – 150,000 ft2 of production facility (running three shifts) is dedicated to custom manufacturing. "We have knowledgeable people on the phones and out in the field supporting our customers with technical information and troubleshooting their problems," Mr Levanduski explains. "A customer may think he has an unusual gripping problem, but chances are we've already designed a solution for it. It may be as simple as modifying a standard product, but many customers have told us that they assumed that custom workholding products would be too expensive or thought that they could make something in-house to solve their gripping problem. Later, they realise that they've compromised the part quality and/or they've created a situation with added set-up and changeover time. In the end, the customer will hand the problem over to Hardinge." BACK IN THE UK This knowledge is reflected at country level as well. In Leicester, home of the Hardinge UK operations, Rob Beckett is the dedicated workholding manager and he co-ordinates all customer liaison through the UK Hardinge sales engineers, as well as working closely with their USA team. "We're very hands on," explains Mr Beckett. "Having the machine tool is one thing, but getting the very best performance from it is quite another. That's where we come in." And he cites a couple of examples. Lister Shearing Equipment, Dursley, Gloucestershire, had a need for special expanding mandrels. The firm is the world's oldest, and the UK's only, manufacturer of animal shearing and clipping equipment, with the majority of the machined and mechanical components manufactured in Dursley. As Lister production engineer Jon Cole explains: "We have a global reputation for manufacturing shearing tools for the professional user and they rightly expect a high quality, high precision product that will give a reliable, extended life. Being a hand-held tool, a shear must only generate minimal vibration and component manufacture is therefore to the very highest precision. Working with Hardinge, we have created a number of fixtures that incorporate special collets and expanding mandrels that have all originated in Elmira. "Being a non-standard size, our requirement could not be satisfied from the standards catalogue, so Hardinge made a fixture for us that ensures high concentricity of a hard turned bearing seat." As standard, Hardinge collet concentricity is 0.0005" TIR, but on specials is 0.0002" TIR or better. And, for Lister, the specifying process could not be easier. "In essence, we consulted with Hardinge, provided drawings that were sent to Elmira and assessed. They made some further recommendations and we then had the completed fixture manufactured stateside and returned to us for fitting to our CNC lathe. Very straightforward." Another UK supplier that makes good use of Hardinge's specials facility is long-standing independent workholding specialist Crenol & Wilson (Workholding), based in Romsey, Hampshire. Founder Norman Crenol estimates it is not untypical for the company to place orders for specials on Hardinge in the order of £9,000 a month and, having worked with Hardinge for over 40 years, he has every confidence in the service and quality. "We are known as a proper 'technical' workholding company and our own design engineers will often be heavily involved in the design of a solution. If our solution involves Hardinge, we then get the manufacturing done in Elmira and over the years there have been minimal problems – not that we were expecting any." The relationship with Crenol & Wilson is two way. The company is Hardinge UK's biggest workholding distributor, but, because it has its own design engineers and workshops, is also a Hardinge customer when manufacturing and supplying many bespoke workholding solutions. "The Hardinge quality is always top end and it is a credit to the company's USA operations and the support in the UK that the supply chain from Elmira is so smooth," Mr Crenol concludes. Hardinge also offers CNC tooling, toolholding and rotary systems – www.shophardinge.co.uk. First published in Machinery, July 2012