Cost & Lead-Time Guide
Small Batch vs Production CNC Machining — Cost Drivers Explained
A part that costs $500 in quantities of 100 might cost $2,000 in quantity 1. Not because the shop is gouging — because setup, programming, and first-article inspection are fixed costs amortized over the run. This guide explains the economics so buyers can budget realistically.
Fixed costs that don't scale
- Programming time — CAM programming for a new part: 2–8 hours typical. Same cost whether 1 part or 1,000.
- Setup time — Fixturing, tool loading, offsets: 1–4 hours per operation. Amortized over the run.
- First-article inspection — Complete FAI on first piece: 1–3 hours. Fixed cost.
- Material minimum orders — Some exotic alloys have mill minimums (100+ lbs) even if you need only one piece.
- Documentation overhead — Certificate of conformance, material traceability, ITP compliance: fixed regardless of quantity.
Per-part costs that DO scale
Machining cycle time × hourly rate = per-part variable cost. Adds linearly with quantity.
Insert consumption scales with quantity but per-part cost is smaller than fixed costs at low quantity.
Cost example
| Quantity | Setup+FAI (fixed) | Per-part cycle | Total | Per-part cost |
|---|---|---|---|---|
| 1 | $1,200 | $300 | $1,500 | $1,500 |
| 5 | $1,200 | $1,500 | $2,700 | $540 |
| 25 | $1,200 | $7,500 | $8,700 | $348 |
| 100 | $1,200 | $30,000 | $31,200 | $312 |
| 500 | $1,200 | $150,000 | $151,200 | $302 |
How to reduce per-part cost
Batch quantities that make sense: quantity 10–25 typically hits a good balance for oilfield work. Quantity 100+ starts amortizing fixed costs efficiently.
For sustainment or emergency work where quantity 1 is required, expect the fixed-cost overhead — it's real, not a markup.
Frequently asked questions
Why does a one-off CNC part cost so much more than a production run?
Setup, programming, and first-article inspection are fixed costs. On quantity 1, those costs are 60–80% of the delivered price. On quantity 100, they're 5–10%. Same fixed cost divided by different quantity.
What's the sweet-spot quantity for CNC machining?
Depends on the part but often quantity 10–25 balances fixed-cost amortization vs total-order risk. Above quantity 100, per-part cost drops slowly.
Can I skip first-article inspection to save cost?
For oilfield/aerospace work, no — quality plans require it. For hobby or non-critical prototypes, sometimes. Ask the shop what's negotiable.
Do CNC shops have minimum order quantities?
Most quote any quantity but the price reflects the setup amortization. Some shops decline very small quantities on complex parts because the per-part cost becomes uneconomic for both sides.