Renishaw technology helps Breton calibrate its in-house machinery

Switching from processing stone materials to metals demands a significant increase in precision. Now Breton uses laser interferometers, rotary axis calibrators, ballbar systems and touch-trigger probes thanks to Renishaw technology. As a result, today, Breton’s range of high-speed, five-axis CNC machining centres are among the world’s most advanced.
 

Calibrate accuracy

Based in Castello di Godego, Italy, Breton has come a long way since its foundation in 1963. Focussing initially on designing and building machinery to process natural stone, the company soon transitioned into also producing complete systems for the manufacture of composite stone (7% polyester content). This innovative material had, in fact, been invented by Breton and proved the backbone of its growing business for many years.

A moment in the rotary axis calibration process

The 1980s saw Breton begin building CNC machinery for processing marble, granite and composite stone slabs aimed at the kitchen worktop and bathroom sector; this particular era also included the arrival of the company’s first five-axis systems. A decade down the line and Breton began to diversify its expertise into the production of high-speed CNC machining centres for the metal-cutting industry. Renishaw technology helped Breton ensure the quality and precision of its in-house production machinery, and its fully assembled machine tools.

Talking about accuracy
Samuele Salvalaggio, Sales Engineering Office, explains how Breton’s own production machines, as well as those the company builds, follow practically the same control and calibration procedures.

“You cannot produce precision machinery if the components are not produced using precision machinery,” he stated. “Our quality control methodology essentially encompasses three phases: linearity control, the checking of axes, and overall control of kinematics, which are all carried out using Renishaw products.”

Ballbar system calibration technology

Once a machine is assembled, a XL-80 laser calibration system is used to test the positioning, linearity and the angular errors of the machine tool. These controls are carried out on all the machine tools produced by Breton. This process is also performed annually on all in-house production machinery and repeated on the rare occasion that deviations are recorded. The company opted for the XL-80 after experiencing difficulties using other systems on axes over 4 metres, a problem which is non-existent with the XL-80.



XL-80 laser calibration system



Machine axes are also the subject of strict quality control routines facilitated by using a Renishaw QC20-W ballbar system. The QC20-W is used to quantify the squareness between each linear axis and to check a machine tool’s fundamental performance via a quick check.

Once staff in the maintenance division, who already used a ballbar system for their periodic checks, showed others how easy to use and accurate the system was, it became a standard tool in every part of the company needing calibration controls.

Among other things, this check is also the first one conducted when customers request technical support for machines installed in the field. At Breton’s 40,000 m2 premises, checking the three linear axes of in-house production machining centres is also a straightforward operational routine. In just 20 minutes the operator can check the condition of the machine and prevent possible manufacturing errors. The ballbar system is now used internally to calibrate the production machines and externally for technical support, particularly when a customer suffers a machine collision.

At Breton, which today employs around 700 people, core business remains the stone processing sector, and here too, despite the fact that precision levels are lower, the benefits of calibration are now fully appreciated. All of Breton’s machines for natural/compound stone processing undergo calibration routines which guarantee their optimum operation.

For more information about Breton's 5-axis machining centers, please write to mail@breton.it.

Many thanks to Renishaw for the provided case study document. 

5 axis machining centers, laser calibration, renishaw