Machine Flashcards

What does the term 'backlash' refer to in a CNC machine's lead screw system?

Answer: The lost motion between the screw and nut due to mechanical play

Backlash is the small amount of lost motion caused by the gap between mating lead screw and nut threads, which can cause positioning errors.

Which CNC machine component converts rotary motor motion into linear table movement?

Answer: Ball screw

Ball screws convert the rotary motion of a servo motor into precise linear movement of the machine table or axis.

On a CNC machining center, what is the purpose of the automatic tool changer (ATC)?

Answer: To store and swap tools into the spindle without manual intervention

The ATC stores multiple tools in a magazine and automatically exchanges them in the spindle, reducing cycle time and manual intervention.

What machine parameter describes the maximum distance an axis can travel from its home position?

Answer: Soft limit (travel limit)

Soft limits are programmable boundaries set in the controller that prevent axis travel beyond the machine's physical range.

A CNC router experiences chatter marks on a flat pocket. Which machine-related cause should be investigated first?

Answer: Worn or loose spindle bearings

Worn or loose spindle bearings allow radial runout that causes chatter and surface finish defects, especially during milling operations.

What is the function of a machine tool's 'home position' (reference point)?

Answer: The fixed machine datum from which all coordinates are referenced

The home position is a fixed machine reference point established at startup so the controller knows the absolute position of all axes.

Which type of CNC machine guide system provides higher rigidity and load capacity for heavy-duty cutting?

Answer: Box way (flat way) guides

Box way guides provide greater surface contact area and inherent damping, making them superior for heavy cuts and vibration resistance.