The crossover is earlier than most engineers expect. For a complex titanium or Inconel part at 1–200 pieces, metal 3D printing (L-PBF) usually beats CNC on total program cost — because you pay no tooling, waste up to 90% less raw material, and consolidate assemblies into one part. CNC wins where geometry is simple, tolerances are below ±0.05 mm everywhere, or volumes run into the thousands. Process names here follow the ISO/ASTM 52900:2021 classification.
When metal AM is cheaper (and when it isn’t)
| Scenario | Winner | Why |
|---|---|---|
| Complex geometry, internal channels, lattices | Metal AM | CNC physically cannot reach internal features |
| Titanium / Inconel, 1–200 pcs | Metal AM | No billet waste; up to 90% less material than machining |
| Assembly of 5–60 parts | Metal AM | Consolidation removes joints, fasteners, fixtures |
| Simple prismatic part, 1,000+ pcs | CNC | Amortized setups beat per-part AM cost |
| Full-surface tight tolerance (±0.01 mm) | CNC (finish) | AM + post-CNC is the usual hybrid answer |
The numbers that decide it
- CNC machining wastes 90–95% of raw stock on complex titanium parts; additive grows only the material the design needs.
- As-built tolerance is ±0.1–0.2 mm; post-CNC ±0.05 mm or better — so finishing, not printing, often sets the final cost.
- No mold and no minimum: the first part costs like the five-hundredth.
A practical rule
Ask three questions before choosing: (1) Can CNC even reach the features? (2) How much raw material would be turned into chips? (3) How many joints could disappear? If any answer points to AM, run the comparison on total cost — tooling, waste, assembly, and inventory included. Cheap stainless grades push the crossover back toward CNC, since there is less billet waste to save — if your part is stainless, our 316L vs 17-4PH comparison covers which of the two workhorses to specify.
FAQ
Is metal 3D printing cheaper than CNC?
Rarely per part, often per program. Hard-to-machine alloys, complex geometry, and low volumes shift the crossover strongly toward AM.
What does a small titanium part cost to print?
A small, simple part typically runs $50–500; large or complex titanium or nickel parts run $500–10,000+ (Ti-6Al-4V feedstock qualified per ASTM F2924). See the stage-by-stage pricing breakdown.
Can you hold CNC-grade tolerances?
Yes — with post-CNC finishing we hold ±0.05 mm or better, which is the standard hybrid route for functional parts.