What Determines CNC Machining Lead Time?
Lead time is the total time from order confirmation to parts arriving at your door. It includes programming, material procurement, machining, finishing, inspection, and shipping. Each phase has its own timeline, and they can sometimes overlap.
Part Complexity
Simple parts with 1-2 setups and standard features program quickly and machine fast. Complex parts with multiple setups, thin walls, tight tolerances, and intricate features take longer to program, require more careful machining, and need more thorough inspection.
Material Availability
Common materials like 6061 aluminum, 7075 aluminum, 304 stainless, and 1018 steel are stocked by most distributors and ship same-day. Specialty materials like Inconel, titanium, Hastelloy, and exotic plastics may take 1-3 weeks to procure.
Pro tip: If lead time is critical, design with common stock materials and avoid outside finishing. As-machined parts in 6061 aluminum can ship in as few as 3 business days from RivCut.
Finishing and Inspection
Surface finishing (anodizing, plating, painting) adds 3-7 days because parts must be sent to a finishing vendor and returned. Inspection level also matters: a standard dimensional check takes minutes, while a full CMM report with FAI documentation can take 1-2 additional days.