By Niraj M Wanikar, Chief Editor, CNCTimes.com, 2019-01-09 12:27:00

Problem statement

Vibrations occur naturally in metal cutting processes, and we have either stable vibrations or unstable vibrations (tool regenerative chatter). When unstable vibration occurs, the severe vibration destroys the cutting process with tool breakage and damaged surface. When a cutting tool is under stable vibration, the machining can keep going at the cost of fast tool wear and unpredictable surface quality.

Vibration damping technology is needed on cutting tools to remove these harmful vibrations and the mass damper is a cost-effective solution commonly used. For mass dampers to efficiently remove vibrations from a cutting tool, its resonance frequency must match the vibration frequency of the cutting tool. Otherwise, the mass damper will fail, and the cutting tool will vibrate.

All machine tools are different, and they are big or small, long or short, new and old, etc. The variation makes the machine tool’s vibration frequency un-predictable and not even to mention the tools vibrating at multiple frequencies. The current mass damper on cutting tools are difficult to use because they are either tuned to a certain frequency or they need frequent tuning to ensure the vibration damping efficiency.

MAQ has invented the STMD^TM technology that will resolve this specific problem.

The innovative self-tuning mass damper

The STMD^TM  products have materials that change its stiffness according to vibration frequency. When frequency goes high, the stiffness goes high and vice versa. These materials enable the self-tuning function on mass dampers and the STMD^TM products adapt itself to your machining condition.

Figure 1, a schematic view of the STMD^TM technology in comparison to conventional mass dampers

As an example of a turning tool, the tool may set up at different lengths for machining different parts. The longer is the overhang length, the lower is the vibration frequency and vice versa. The tool will vibrate at different frequencies depending on the overhang length. The STMD^TM products cover a wider frequency range, correlated to the L/D ratio (length to diameter ratio), see the example in Figure 2.

Figure 2, vibration amplitude comparison between competitor and MAQ STMD^TM products on a cutting tool at different L/D.

Productivity enabled by MAQ STMD^TM

Cutting process parameters (speed and feed) are conservative when the risk of unstable vibration is considered. With STMD^TM  technology, there is no need to worry about the vibrations and you are at a free-mind to press the ‘start’ button.

Figure 3 surface finish comparison between the competitor products and MAQ STMD^TM products in a turning process

High-speed machining excites multiple frequency vibrations on cutting tools and MAQ STMD^TM will adjust itself to damp both the high and low frequencies automatically. With MAQ STMD^TM inside, you will be able to cut at high speed and high feed.

See our demo video where we made machining in SS2541 with 500 m/min speed at 11 L/D https://www.youtube.com/watch?v=2grBSvpWNjM .

Distributor in India: CaaM CNC Machines & Automation, Bengaluru.

Contact Person: Mr. Suresh Bhat – Managing Partner & CEO

Mobile No. : +91 – 9448376319

Email: caam.cncmachines@gmail.com

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