Precision CNC machining demands tight repeatability to keep part-to-part variation inside tolerance. Thermal growth, tool wear, fixture shifts, measurement error, and material inconsistency are the main drivers. Statistical process control charts and measurement system analysis identify root causes quickly. Real shop examples—aluminum ribs, stainless stems, copper EDM parts—show reductions from 0.018 mm to 0.005 mm spread using live compensation and gage studies. Practical steps include baseline audits, torque control, coolant discipline, and regular GR&R checks, delivering higher yield and fewer customer complaints.
Effective workholding in CNC machining requires sufficient force to prevent movement while avoiding distortion from excessive pressure. This article reviews distortion mechanisms, traditional vises and chucks, and advanced vacuum, magnetic, and adaptive solutions. Shop examples and journal studies demonstrate practical methods to distribute clamp loads evenly, monitor forces in real time, and integrate fixturing with toolpath strategies. Implementation of these techniques routinely achieves flatness and roundness tolerances below 0.002 inches across aluminum, steel, and titanium components.
