45,000 operating hours. This is how long - or even longer - a 15-year old cylindrical grinding machine is in use. Anything that does this much will wear, and this particularly shows itself in the geometry and precision. High time to give the machine a good overhaul. A machine overhaul at STUDER makes an old machine into one that is as good as new; in other words, a machine that has the same tolerances as when it was first delivered. If the requirements on the machine have also changed, the machine can be configured and retrofitted to the customer's requirements during the overhaul.

The S40 was in use at LMT Kieninger for 14 years. The company specializes in highly demanding machining tasks and manufactures special tools for die and mold making. "The S40 was the Rolls Royce of grinding machines. But the machine still wears over time and after intensive use", admits Heiko Braun, Group Manager of Cylindrical/Surface Grinding and Assembly. It was clear to LMT Kieninger that they should send the cylindrical grinding machine to the STUDER factory in Switzerland for an overhaul. STUDER provided them with a loan machine for around three months and took care of everything from A to Z - from collection through to customs formalities. "We were very satisfied with the loan machine. Apart from a few little things, we were able to continue grinding as usual", sums up Braun. The special feature about a machine overhaul at STUDER? It is the only company to refurbish the machines' guideways to the original specifications. After the assemblies have been reinstalled, the machine geometry is equivalent to that of a new machine. Braun's view:

A rebuild, or a machine overhaul, makes sense, and not just economically. The operator gets his familiar machine back and continues where he stopped before the overhaul. But he is full of enthusiasm! Because his old machine is like new. In the STUDER factory the specialists disassemble the machine into all its individual parts. The guideways are completely refurbished, the assemblies overhauled, the wear parts in the electric cabinet replaced, hydraulic and lubricating system as well as all valves replaced. If old spare parts can no longer be obtained, STUDER provides an alternative solution. The casing and components are sand-blasted and then given a fresh coat of paint. After assembly the geometry is like that of a new machine. Commissioning is carried out by STUDER Customer Care, including a functional and geometry inspection, all CE-compliant. "Over 20 people work on machine overhauls at STUDER. This shows the value of rebuild and retrofit at STUDER. The customers are always enthusiastic about the transformation and are delighted to put an as-new machine into operation at an excellent price-performance ratio", says Marcos Cotarelo, Divisional Head and Customer Care Consultant.

The S21 is the second factory-rebuilt STUDER machine at Ingold Tools AG. In 2016 the company took on a second-hand S31 machine, which STUDER overhauled. "We grind to a bearing tolerance and diameter of 1my. STUDER guarantees this accuracy after the overhaul. Either way: An overhauled STUDER will run just as long as a new machine", attests Stich. Jenzer and Stich see a further advantage of the machine overhaul in the operation: "The employees don't have to get used to a new machine with a new control system."

Ingold Tools has relied on STUDER since it was established in 1946. The first external cylindrical grinding machine was a type 01 from the year 1955. This was still in use when Christoph Jenzer joined the company 13 years ago. "We like working with STUDER. The service personnel are quick to respond, and our Customer Care Consultant supports us wherever he can. It's not without reason that we have so many STUDER machines." A new machine? Jenzer and Stich say: "We wouldn't rule it out – a new machine always offers advantages which an old one doesn't have, such as faster travel in all axes, simpler set-up of the machine, and easy programming with less technical knowledge." But the employees are looking forward to the overhauled S21, which will soon be on its way to Inkwil in Bern.