He continues: "The NC4 also allows us to check for breakages of small tools used to make keys and other reference points on the cam, which are vital if the engine is to operate properly.  If it wasn't for the Renishaw system, the machine could, for example, operate with a broken cutting tip, with disastrous results.  Furthermore, since tools are checked for breakage automatically, one operator can easily manage both machines: all he needs to do is load the pieces and ensure that everything is running smoothly."

Process control critical to machining operations

As Abbondi describes: "The first thing we did was to install a system provided by the machine tool manufacturer, which enables the power used by the spindle motor to be checked. This system checks the degree of wear of the larger bits, used to drill the deepest holes, in which the stress during machining is more apparent - if the torque increases, it means that the tool is worn and so the alarm goes off. But we also needed, quickly and reliably, to detect when tools break, even the smallest ones, which usually manage to escape most detection systems."

Conventional contact-detection systems have certain weak points and are usually unsuitable for small tools - the tool is brought into contact with a ‘button' or ‘rod' which activates the device. There is also the danger that the contact itself could break or damage the tool. This means that work can only be done at low speed, which slows down the process and considerably lengthens cycle times. The systems must often be fitted inside the operating area, occupying valuable space and causing possible collision risks, not to mention poor reliability due to the fact that they tend to jam. This is why the Renishaw system was adopted, to replace these devices.