Used for micro-machining, NTC’s Zµ3500 operates with zero metal contact for increased rigidity, accuracy and repeatability. Traditional machining centers include calculated NC offset functions within the control to compensate for inherent inaccuracies from backlash and other mechanical-tolerance issues, the company says. However, the machine functions without linear guideways, roller bearings or ballscrews to avoid compromising tolerances.
Furthermore, the zero-metal-contact design eliminates major sources of friction and related thermal distortion, the company says. The use of temperature-controlled hydrostatic oil in the hybrid spindle bearing, static pressure guides and a linear-motor cooling system reduce thermal distortion saturation time. According to the company, the near-absence of friction (and therefore vibration) increases precision, extends tool life and reduces noise levels.
The machine’s spindle incorporates hydrostatic and hydrodynamic technologies to reduce wear and runout. At 25 hp, it reaches speeds of 30,000 rpm. The spindle uses HSK E32 toolholders, and the 12-tool ATC is fully enclosed. Travels are 13.78" in the X axis and 11.8" in the Y and Z axes. Positioning is accomplished with cooled-scaled linear motors with 0.6-G acceleration.