BLUM laser measuring systems at the famous Swiss timekeeper, Christophe Claret SA.

Measuring Components

Ultra-high precision partner

For many years, the precision engineers of the world-renowned Manufaktur Christophe Claret of Le Locle in the Swiss Jura have relied on Blum-Novotest to equip its processing centres with production instrumentation. The name of Christophe Claret stands for excellent quality among clockwork manufacturers. 

Working with a passion
Christophe Claret himself took to watch making as though it were a religious vocation. Micro-engineering is his creed. This passion that has driven him since his childhood, comes from his fascination for high-precision, small-scale engineering: that of making watches. Their complexities and perfections have become, through observation and work, his real reason for living and exercising this art of great accuracy. 

First self-educated, then trained by the best Swiss specialists who introduced him to the craft’s secrets, he started by buying, restoring and re-selling ever more complex watches before embarking on his own first creation. 

Mastering tourbillons, repeaters, musical precepts, minute repeaters with Jacks, chronograph, fly-back hand with insulator, perpetual day with bi-retrograde etc., Christophe Claret searched for perfection at all levels, from the design and simulation (CAD) of a new movement to its final assembly in order to produce a unique masterpiece. 

From 1987, he has supplied exclusive movements to prestigious watchmakers such as Guy Ellia and Jean Dunand. Creator of several world ‘firsts’, the micro-mechanism artist developed and transposed his ideas in the spirit of client brands who assemble the movements. 

Clean atmosphere, controlled temperature and sometimes noise absorbers are de rigueur for the 2,000 sq. metres of workshops. The components are manufactured on the ground floor. On the first floor, in a controlled atmosphere, every movement is meticulously assembled by experts. The founder‘s disciples are young (average age 28) and already highly talented.

Closest production tolerances
Precision to the scale of a hundredth of a millimetre is standard, however the workshop often shapes to the scale of a micron or even a nanometre, which is the measurement for some digital controls. The flow controls organise production from some 8,000 operative ranges, to which are added some 2,000 variations. The batches are very small, sometimes only about fifty parts, launched at the rate of five per year. 

Christophe Bouveret, production manager at «Le Soleil d’Or» explains: “When highly complex watches are manufactured, a considerable number of parts is needed. Thus, we have designed 30 calibres made up of 450 parts on average. The more parts, the more precise is the tolerance of each element. In this context, if the components are not machined according to very stringent precision criteria, the tolerance gap is no longer acceptable“.

Highly modern machine tools
The machinery meets all requirements in terms of milling, boring, electro-erosion, laser cutting, profile turning, gear-cutting, burnishing etc. The workshop includes 18 CNC machining centres (the oldest is only four years old). These units perform to a scrap rate rarely above 1 %. 

Combined machine-tools (prismatic and revolving parts) are preferred, because they allow milling in three, four or five axes. The aim is to complete fully each part in one go, with tolerances in the range of five microns either way, using standard or special tools.

The safe way to the highest precision
Given its high-technology level, the up-market watch making world is a very closed shop for confidentiality reasons. Yet the factory in Le Locle has no hesitation in revealing one aspect of its efficiency and manufacturing quality assurance: the systematic use of the BLUM LaserControl NT-H for thousands of tools, drills, bits, taps, milling cutters etc., which every day have to be examined and measured before machining use. 

Programmable by built-in microprocessors, this third-generation laser technology to measure cutting tools, ensures reliability even in extreme conditions. It provides maximum machining precision and the systematic verification of cutting edges at all rotation speeds.

Monitoring of special tools
Tool pre-setting, measurement with or without contact, runout control, marking of runner (or taper) defects without the risk of collision are the system’s properties, including diamond shaped or CBN cutting edges.

The monitoring also includes the examination of standard or special tool shapes with the precise marking of the number of teeth when milling. Everything is systematically integrated into the programming of the machines before production starts. LaserControl NT-H is capable of carrying out these measurements even with very fast rotating tools, thanks to high precision optics and to its focused laser beam.

Christophe Bouveret concludes: “We have chosen the most effective system for measuring and monitoring tools. Above all, we search for reliability. The system designed by BLUM meets all of our criteria expectations, since it is capable of coping with very small tool diameters to the scale of a tenth of a millimetre. LaserControl has become indispensable for measuring our tools correctly at all times before machining.“

Significant productivity gains
He adds, “Productivity gains are really substantial. Previously, we wasted a considerable amount of time in pre-setting by conventional means and the wear of tools was not detected in the machine tool. And, very importantly, it is the automatic introduction of tool data into the machines’ digital controls which was, until then, a manual task with the risk of error. To summarise, it is a system that allows us to guarantee quality and, simultaneously, much higher productivity.“

www.christopheclaret.com