You can often cut a machined part price by 20 to 50 percent without touching the parts that actually matter to function. The trick is knowing which design and ordering decisions move the number and which ones only add cost for no benefit. This is a practical, engineer-tested checklist for how to reduce CNC machining cost while keeping the tolerances and finishes your part truly needs.
Loosen tolerances everywhere they are not critical
This is the highest-leverage move by far. A blanket +/-.001 in across a print is a silent budget killer. Reserve tight tolerances for the features that mate, seal, or bear load, and open the rest.
- Keep +/-.0005 in only on bearing journals, seal bores, and press fits.
- Use +/-.005 in or looser on clearance holes, cosmetic faces, and overall lengths.
- Default non-critical dimensions to a standard block tolerance instead of calling out each one tight.
Opening a single non-critical feature from +/-.0005 in to +/-.005 in can remove a finish pass and an inspection step. See our quality and inspection page for how we set inspection sampling to match tolerance, so you never pay to measure a feature that does not need it.
Batch your orders to spread setup cost
Setup and programming is a fixed cost of $500 to $1,200 for a typical part. Order one and it lands on one piece. Order 100 and it disappears into pennies per part.
| Quantity | Setup cost per part | Effect on unit price |
|---|---|---|
| 1 piece | $500 to $1,200 | Highest per-part price |
| 25 pieces | $20 to $48 | Sharp drop |
| 100 pieces | $5 to $12 | Setup nearly disappears |
| 500 pieces | $1 to $2.40 | Machine time dominates |
Order annual usage, release as needed
If you use 300 parts a year, quote 300 and take releases on a schedule. You get the volume price while managing cash and inventory. Ask about blanket orders when you request your quote.
Pick the most machinable material that meets spec
Material choice is a quiet cost lever. If 6061 aluminum or 303 stainless meets your requirements, do not default to 316 or 17-4 out of habit.
- Aluminum 6061: fastest cutting, lowest cost, great for brackets and housings.
- 303 stainless: free-machining, use it over 316 when corrosion resistance allows.
- 12L14 or 1215 steel: excellent machinability for non-corrosive parts.
- Avoid over-specifying titanium or Inconel unless heat or strength truly demands it, since those can run 3x to 7x aluminum.
We supply DFARS-compliant material with mill test reports, so choosing a cheaper qualified grade does not cost you traceability.
Design to cut the number of setups
Fewer setups means less labor, less fixturing, and tighter true position. Simple design moves keep parts to one or two setups.
- Group features on as few faces as possible.
- Avoid a lone hole or boss that forces an extra flip.
- Add a datum face or edge the shop can locate from quickly.
- Let the shop suggest orientation, our CNC milling team reviews every job for setup reduction.
Design features that match standard tooling
Custom or tiny tools are slow and expensive. Match your geometry to common cutters and you buy speed for free.
- Internal corner radii: specify at least a 1/8 in radius so a standard end mill can reach it in one pass.
- Hole sizes: use standard drill diameters instead of oddball callouts.
- Pocket depth: keep depth under 4x the tool diameter to avoid slow long-reach tooling.
- Threads: use standard tap sizes and avoid unnecessarily deep threads past 1.5x diameter.
- Wall thickness: keep walls above 0.040 in to avoid chatter and slow light passes.
Use the right process for the part
Matching the part to the machine is a cost lever most buyers miss. Round parts belong on a lathe, not a mill.
- Round, symmetric parts: route to CNC turning, far cheaper than milling from bar.
- Small precision parts under 32 mm: Swiss machining runs them fast and unattended.
- Prismatic parts: a horizontal machining center wins on volume.
Simplify finishing and paperwork to what you need
Do not order a mirror finish or full first article inspection unless the application requires it.
- Accept as-machined Ra 125 uin where cosmetics do not matter.
- Ask for a clear anodize only on surfaces that need corrosion protection.
- Request first article inspection where it adds value, not reflexively on every part number, since it runs $150 to $600 each.
We run an ISO 9001-aligned quality system with in-house CMM, so you get the documentation you actually require without paying an outside lab.
Turn the checklist into a lower quote
Every figure here is a typical illustrative estimate, not a binding quote, and your savings depend on your specific part. The fastest path is to send a model and print through our instant quote, and we will mark up exactly where you can reduce CNC machining cost without touching the features that matter.