DECISION GUIDE
Forging vs CNC machining:
the real cost comparison.
Both processes make the same part. They just charge you for different things — and which one wins depends on numbers you already have.
Quick answer
CNC machining from solid wins for prototypes and small runs — no tooling, instant start. Forging plus finish machining wins at volume: you pay for a die once, then every part after it is cheaper, stronger and faster to make. The crossover point is a volume — and it’s knowable before you commit.
What you’re actually paying for
A machined part’s price is mostly spindle hours and bought material. You purchase a block at finished weight plus 50–80% extra, then pay a machine to remove that extra as chips. A forged part’s price is mostly die amortisation plus near-net material — the press forms the geometry in seconds, and machining only touches critical faces.
| Dimension | Forged blank + CNC | Machined from solid |
|---|---|---|
| Cost driver | Die + press cycle + light machining | Machine hours × material bought |
| Material used | ≈ finished weight + flash | Finished weight + chips |
| Tooling | Required (in-house at XPF) | None |
| Best batch | Mid to high volume | Prototype to small series |
The crossover is a volume — here’s the logic
Forging adds a fixed cost (the die) and lowers the variable cost per part. Machining has zero fixed cost and a high variable cost. Somewhere between those two lines is your break-even quantity. What moves it:
- Annual volume — more parts spread the same die cost thinner
- Buy-to-fly ratio — the more material machining removes, the more forging saves
- Geometry — 3-D structural shapes pay back fastest; flat plates rarely justify a die
- Machining content — long cycle-time parts convert best
On qualifying projects we’ve reported around 40% unit-cost reduction . That is a project outcome, not a promise — your numbers decide yours.
Strength changes too
Forging isn’t only about cost. Bar stock has straight grain; machining cuts through it at every feature. Forging moves the grain around the part’s shape — following the load paths. For fatigue-loaded parts (crank arms, links, brackets) that’s the difference between a part that survives and one that doesn’t.
When we tell you to keep machining
R&D prototypes. One-offs. Parts still changing every month — tooling them early wastes money. Send those to any good machine shop (or ours — we machine too). Convert when the design freezes and the volume justifies it.
How to get your crossover number
- Send the drawingSame file your machine shop has — STEP / DWG / PDF
- Free conversion reviewFeasibility, route, cost range at your volume
- Decide with numbersDie cost vs per-part savings — on one page
Want your crossover number?
Free conversion review — one drawing is enough.