Less is more …
Sinumerik 828D on the shopfloor at Metallbearbeitung Kamusin GmbH
At the end of June 2020, Bavaria began easing its lockdown restrictions put in place to fight the coronavirus. After months of being limited to online research only, the CNC4you team's first on-site meeting took them to Metallbearbeitung Kamusin GmbH in Schwebheim near Schweinfurt in Bavaria, Germany. We went into the meeting feeling somewhat uneasy. What kind of reception will we get from the customer? Is the general mood so subdued that it will be difficult to produce a good story? Far from it ...
Although the order situation at Kamusin could of course be better, the mood is still positive. There is talk of innovations and realignment of production. In fact, a lot has happened at Kamusin in the last decade, so it's worth beginning with a brief retrospective.
At the turn of the century, Ingo Kamusin and his wife decided to start a small contract manufacturing business with conventional machines. The couple quickly realized that the business concept of serving the metal working industry in and around Schweinfurt promised to be a great success. Kamusin invested in CNC machines to meet its customers' quality criteria and their expectations in terms of delivery times. The firm expanded, the original machine shop became too small and the facility moved to a spacious building in the nearby industry park.
Challenges due to shortage of qualified personnel
The machine park had now grown to some 12 machines, and 15 employees were working in production, but it was difficult to find good, qualified machinists in a rural area. Many qualified employees were attracted to large industrial companies located around Schweinfurt. So Ingo Kamusin tried training staff himself, but unfortunately, without any lasting success. There just weren't enough interested applicants. And if they did find one, the newly qualified machinist quickly moved on to another job after successfully completing the training. Ingo Kamusin is critical of a change in society that sees technical professions such as that of a qualified CNC machinist becoming increasingly unpopular.
Back to the roots!
As a consequence, Kamusin gradually reduced the size of its staff. Back to the roots, as they say. Kamusin returned to the core competences that had made the small company so successful: developing and optimizing components – in close collaboration with its customers. The move took them away from the extreme cost pressure associated with contract manufacturing alone and toward prototype construction and development.
The family is the key to success
The company's concept works because the whole family is involved in the firm. The owner's wife runs the office, where she is in charge of everything from order processing to salaries, while son Tim – having successfully completed his training as a qualified CNC operator and spending a number of years working outside his father's business – contributes a great deal of drive and an abundance of new ideas. Daughter Lena has also dedicated herself to machining and is just finishing her vocational training before joining the team in Schwebheim.
Kamusin now employs just three other people besides the family. The economic disruption caused by the corona lockdown has made Ingo Kamusin appreciate the company's new set-up even more. He does not have to consider the capacity utilization rates of a large number of employees but has the freedom to think creatively about the future. Son Tim in particular contributes a lot of new ideas to the business. It was his idea to gradually replace the existing machinery with Sinumerik-controlled machines: "Today Sinumerik allows me the flexibility to program and machine both high- and low-volume production runs with ease. I came to appreciate its benefits back in the days when I was training to become a CNC machinist. Sinumerik is now the perfect CNC for us at Kamusin."
No other will do …
The typical low-volume or one-off jobs handled by Kamusin call for operation and programming that are simple to understand yet provide the flexibility to manufacture complex components or take on occasional high-volume components.
The two Hyundai Wia HD 2200 SY and L250Y turning machines are both equipped with the Sinumerik 828D. Many one-off parts are programmed on the control system itself with the aid of the wide-ranging functions of ShopTurn graphic programming. Using ShopTurn makes it possible to create a part program that mirrors the thinking of the operator standing in front of the machine. The program is generated step by step by combining individual operations. The operations are represented by the machining cycles (macros).
However, Tim Kamusin does not feel restricted in implementing his components by this exclusively graphic form of programming. On the contrary, he is excited by the option of freely mixing graphic programming with G-code blocks. There is one solution that he finds particularly ingenious, and that is the fact that many input fields in the cycles of the ShopTurn programming interface can be described with user variables (also called R-parameters), which can also be used for arithmetic operations.
This is particularly valuable when machining part families in which the components are largely identical, but where there is variation in diameters, drilling positions, drilling diameters, component lengths or some other parameter. All that is needed in such cases is a main program in which the right component version is selected at the beginning of the program by defining an user variable. The program itself remains untouched.
Intuitive use of counterspindle functions
The Hyundai Wia HD 2200 SY turning machine has a main spindle and a counterspindle. Here too, the Sinumerik 828D boasts maximum ease of operation. The intelligent counterspindle cycle in ShopTurn enables graphically interactive programming of the counterspindle – from simple support all the way to automated workpiece flow with bar loaders. Tim Kamusin is enthusiastic in his praise: "The counterspindle functions open up an enormous range of options that are simple to handle using ShopTurn. The entire workflow of transferring from the main spindle to the counterspindle is easy to control by means of the graphically supported input fields." Clamping, pulling, releasing, synchronizing, traveling to parting position, mirroring the machining and many more operations can be controlled in this way. It did not take long until Kamusin had achieved perfect integration of the new machine into its production.
Having this equipment available makes it easy for Kamusin to accept smaller orders. For example the manufacturing of connectors for design wine racks of the company VINSIA. The component shown in the photos can be created to perfection with the aid of the counterspindle, the driven tools, the milling operations and the Y axis. Job planning requires little effort. In just 15 minutes, Tim Kamusin programmed the component on the control system itself using ShopTurn.
Measuring in the process
The option of being able to perform high-volume production runs was also taken into consideration when selecting the machine. The turning machine has an additional bar loader and is also capable of producing high volumes in unmanned operation. Kamusin invested in measuring instruments from Blum for measuring in the process and to ensure process reliability. A Blum TC54-10 measuring probe is used for measuring workpieces on the machine. Measurements in X+/-, Y+/- and Z+/- are possible with a star-shaped or t-shaped probe tip thanks to the multi-directional, face-geared measuring mechanism.
The probes are rated with IP68 protection and are suitable for reliable measurements up to a measuring speed of 2000 mm/min even when coolant is flowing. Typical measuring tasks on turning machines are measuring a slot (C axis measurement), outer and inner diameter, length and positioning. As the Sinumerik 828D includes a whole selection of measuring cycles, the measuring probes are also easy to use from the control system.
And the results of the measurements can not only be used for correcting the workpieces, but also for fully automated detection of tool wear and updating tool data.
The Kamusin story goes on. A new milling machine will be delivered in the fall. Once again, there is no question about the choice of CNC: Sinumerik is a must for any machine entering the Kamusin machine shop. As operation of milling and turning machines with Sinumerik has been completely standardized, Kamusin expects their operators will need little time to familiarize themselves with the new machine. We are already looking forward to our next visit to the friendly family business.
Birthday greetings to Sinumerik
Finally, a birthday greeting from Tim Kamusin to the Sinumerik family, which is 60 years old this year:
Today Sinumerik CNC allows me the flexibility to program and machine both high- and low-volume production runs with ease. I came to appreciate its benefits back in the days when I was training to become a CNC machinist. In my opinion, Sinumerik is the best CNC in the world today. Keep it up!Tim Kamusin, junior director at Metallbearbeitung Kamusin in Schwebheim
The technology in detail
The counterspindle cycle in ShopTurn
If a CNC turning machine is equipped with a counterspindle, workpieces can be manufactured in a time-optimized manner. A further advantage is that by using two spindles, workpieces can be manufactured more accurately in terms of shape and position tolerances.
The ShopTurn counterspindle cycle makes it easy to work with two spindles.
Entering spindle chuck data
The spindle chuck data must be set correctly for this purpose.
The values entered here are included for all subsequent machining operations with the counterspindle cycle, ensuring exact transfer and machining.
Now the counterspindle cycle can be mapped.
- the zero point for the counterspindle is calculated on the basis of the machine's geometry data
- length of finished part
- position of counterspindle in the machine coordinate system
The following video tutorial shows all this in context: