CNC Machining
Services
Built to Spec. Delivered on Time.
Custom CNC machined parts from a vertically integrated China facility — ±0.005 mm tolerances, 3/4/5-axis milling and turning, prototype to production. Engineering team on every project.
Common Challenges in CNC Machining Sourcing
Engineers and procurement teams run into the same walls, again and again. Here's what actually goes wrong when sourcing precision machined components.
Tolerance stack-up across multi-step setups causes out-of-spec deliveries
When a part requires repositioning between ops — turning, then milling, then drilling — cumulative datum shift can push GD&T callouts beyond acceptable limits, even when individual operations pass.
GD&T / Datum shiftLead time collapses under engineering change orders mid-production
ECOs issued after tool paths are programmed or first articles are cut force full re-quoting cycles, scrapped fixtures, and schedule slippage — most suppliers can't absorb late-stage design revisions without a hard reset.
ECO / Lead timeMaterial and surface finish specs are misinterpreted without DFM dialogue
Callouts like "Ra 0.8 µm" or "6061-T651 anodised to Mil-A-8625 Type II" leave room for interpretation. Without upstream DFM review, suppliers substitute process routes that meet spec on paper but fail in application.
DFM / Surface finishInspection reports lack traceability — no CMM data, no measurement plan
A CoC alone doesn't give your QA team what it needs. Parts arrive without a dimensional report tied to a control plan, making incoming inspection a full re-measurement exercise and blocking assembly line release.
QA / CMM traceabilityPrecision problems need engineering answers
We don't just machine parts — we work through the failure modes before a single chip is cut.

One setup eliminates datum shift — complex geometry, single clamping
Our simultaneous 5-axis machining centers cut compound angles, deep pockets, and undercuts in a single clamping event. When repositioning is eliminated, tolerance stack-up is eliminated — critical for parts with tight positional callouts across multiple features.

24H DFM feedback closes the spec gap before you commit to tooling
When we receive your drawing, our engineering team reviews material spec, surface finish callouts, critical GD&T features, and process route before quoting. If a callout is ambiguous or manufacturing-hostile, we flag it — not after the first article, but before the order is placed.
CNC Machining Specifications
Key parameters at a glance — answers to what your engineering team asks before sending an RFQ.
Materials & Surface Finishes
From certified raw stock to finished surface treatment — everything under one roof, qualified to your drawing.

We stock and machine a broad range of engineering metals and plastics — sourced and certified with full material traceability.
Post-machining treatment applied in-house or through certified partners. Specify on your drawing or discuss with our engineers — we confirm compatibility before quoting.

CNC Machined Parts — Milled and Turned Components
Precision CNC milling and turning services for industrial, aerospace, medical, and energy applications. Tolerances to ±0.005 mm, ISO 9001 certified, full CMM inspection reports.
Precision CNC Parts We Machine
A cross-section of milled and turned components — from prototype quantities to high-volume production runs. All parts held to ±0.005 mm with full CMM dimensional reports.

±0.01 mm port concentricity

Hard anodised, bore ±0.01 mm

Freeform blade, Ra ≤ 0.8 µm

Medical grade, ±0.005 mm

Implant grade, full CMM report

Cavity Ra ≤ 0.4 µm

Bolt circle ±0.005 mm true position

Multi-bore alignment ±0.01 mm

Micro-orifice array, Ra 0.4 µm bore

3D profile form tol. ±0.01 mm

Runout ≤ 0.005 mm

OD/bore concentricity ±0.005 mm

Cylindricity ≤ 0.003 mm

Position tol. ±0.008 mm

Straightness ≤ 0.01 mm/m

Cylindrical grinding, Ra ≤ 0.8 µm

Journal ±0.005 mm, gear DIN 6

Step concentricity ±0.005 mm

Offset ±0.008 mm, dynamic balance

Pin journal ±0.005 mm, ground finish

Wall thickness ±0.05 mm

Runout ≤ 0.003 mm, batch ready
Quote in 24H. Parts in 5–7 Days.
CNC Machining Capabilities
From complex milled housings to precision turned shafts — all processes in-house, all under ±0.005 mm.
3 / 4 / 5-AxisPrecision milling for prismatic, complex-contour, and thin-wall parts. Single or multi-setup, prototype to production.
CNC TurningHigh-precision turning for shafts, cylinders, and rotational components. Long-shaft and cylindrical grinding in-house.
5-Axis · Turn-MillCompound angles, freeform surfaces, and multi-feature parts machined in a single clamping — no datum shift, no repositioning errors.
CNC Machining for Critical Industries
Precision parts for applications where tolerances, traceability, and on-time delivery are non-negotiable.
MedicalTi Gr.23 · SS 17-4PH · Full CMM traceability
Energy42CrMo4 · SS 316 · High-pressure rated
AutomotiveAl 6061 · GG25 · 20CrMnTi · Batch ready
AerospaceTi Gr.5 · Al 7075 · Tight GD&T callouts
Quote in 24H. Parts in 5–7 Days.
Engineering Case Studies
Real projects, real challenges, real results — documented so you can evaluate our capability against your own requirements.

55 custom solid steel balusters, ~1,000mm length, continuous taper. Local US suppliers declined — vibration and chatter on long tapered shafts exceeded their capability. 20-day DDP deadline.

Al 6063-T6 structural bracket for ruggedised military computers. Wall 5.1mm, unilateral tol. 0/−0.05mm, flatness ≤0.1mm, zero chatter. Standard machining practice insufficient.

Rudder control gearbox: 38mm Ø, 12 N·m, backlash ≤3 arcmin, −45°C to +120°C range. 20 validated prototypes needed in 3 weeks — for flight qualification of a European defence UAV programme.
Quality Control & Precision Inspection
Every part ships with documented proof — not just a verbal assurance. Here is exactly what happens between machining and your dock.

From Engineers & Buyers Who've Worked With Us
Unedited feedback from procurement managers and engineers across North America, Europe, and beyond.
Precimach responded faster than any domestic supplier we'd approached. They kept us informed throughout, delivered a full week ahead of schedule, and the surface finish on the balusters was exactly what we needed for visible architectural installation. We came back for the production run.
Their inspection reports and documentation meet our internal standards — full CMM reports, material certs, CoC with lot traceability. The DFM feedback before production started flagged a tolerancing issue our own team had missed. Working with Precimach has materially reduced our supply-chain risk on these parts.
We moved from prototype to full production without any re-qualification process — the prototype batch and production batches came in dimensionally identical across all critical features. Quality has been consistent across multiple orders. Lead times are reliable. That's all we need from a machining partner.
Frequently Asked Questions
Straight answers to the questions engineers and procurement managers ask us most before placing an order.
Prototypes (1–10 pieces): typically 5–7 working days from drawing approval to parts shipped. For straightforward turning or milling in common materials, we often complete in 3–5 days.
Low-volume production (10–200 pieces): 7–15 working days depending on complexity, setup requirements, and surface finish.
Volume production runs: quoted individually — contact us with your annual volume and we'll advise on scheduling and inventory options.
All lead times are from drawing approval, not from enquiry. Our 24H DFM feedback means most orders are in production within 48 hours of first contact.
General machining tolerance: ±0.005 mm on standard features. Tighter tolerances (±0.002–0.003 mm) are achievable on specific features with the correct process and fixturing — discuss your requirements during DFM review.
Surface roughness: Ra 0.2 to Ra 3.2 µm. Mirror finish and cylindrical grinding available for bearing and sealing surfaces.
Verification: every first article is measured on our CMM against your drawing. The dimensional report — actual vs nominal for every callout — ships with the parts. We don't release on operator feel; we release on measured data.
Accepted formats: STEP (.stp), IGES (.igs), SolidWorks (.sldprt), CATIA, Parasolid — plus 2D drawings as PDF, DWG, or DXF. We can also work from sketches or reference samples for reverse-engineering.
To quote accurately, we need: 3D model + 2D drawing with tolerances, material specification (grade, not just type), surface finish requirements, and target quantity. The more complete your package, the more precise the quote.
If your drawing is incomplete or you're still in design, send what you have — our engineers will work with you to fill the gaps during DFM review.
Yes — we sign NDAs before reviewing any drawings or technical information. This is standard practice for all projects, not an optional add-on.
How it works: send us your NDA template and we'll review and return a signed copy, typically within 24 hours. If you don't have an NDA template, we have our own standard confidentiality agreement we can provide.
Drawings and technical data are held internally and are not shared with third parties. All manufacturing is performed in our own facility — we do not subcontract machining work.
We ship worldwide via DHL, FedEx, and UPS air freight. Standard transit time to the US East Coast is 3–5 business days from our facility in Suzhou, China; West Coast is 2–4 days; Europe 4–6 days.
DDP (Delivered Duty Paid) is available to most destinations — we handle export customs in China, international freight, import customs, and local delivery. You receive the parts at your door with no additional charges to manage.
DAP (Delivered At Place) is available if you prefer to handle import duties yourself. We provide a full commercial invoice and packing list for customs clearance.
We machine a broad range of engineering metals and plastics. Commonly ordered materials include:
Material certifications (mill certs) with heat number and lot traceability are provided as standard on all orders. If your application requires specific certifications (RoHS, REACH, DFARS-compliant stock), let us know at the quoting stage.
Non-conforming parts are our responsibility to correct — at no cost to you. Our process is:
1. Documentation first: share your incoming inspection findings with us — photos, measurements, or CMM data. We compare against our outgoing inspection records to identify the discrepancy.
2. Root cause and corrective action: we identify what went wrong in our process and issue a formal corrective action before re-manufacturing.
3. Expedited re-production: replacement parts are prioritised and shipped at our cost. We also cover return freight for the non-conforming batch.
In practice, our first-article CMM verification process means non-conforming deliveries are extremely rare. But when they happen, we don't dispute — we fix.
Minimum order quantity: 1 piece. We routinely produce single-piece prototypes — this is a core part of our business, not an exception we reluctantly accommodate.
For single pieces and very low quantities, unit cost will be higher due to setup time. We'll tell you exactly what drives the cost, and in many cases we can suggest design or process adjustments during DFM review that reduce it without affecting function.
Once your prototype is validated, we retain the process data, fixturing, and inspection plan — scaling to production volumes adds no re-qualification delay.
We are ISO 9001:2015 certified — our quality management system covers the full production cycle from order intake through final inspection and shipment. Certification documentation is available on request.
Audits: we welcome customer quality audits, either on-site at our Suzhou facility or via virtual audit (video walkthrough of processes and equipment). Several of our long-term clients conduct annual supplier audits — we support this as part of a normal supply chain relationship.
What we provide with every shipment: CMM dimensional report · Certificate of Conformance · Material test certificate with lot number · In-process inspection records (on request).
Our engineering and project team responds in English within 24 hours on business days — typically much faster. We communicate via email, WhatsApp, or WeChat, depending on your preference.
During production you will receive: confirmation when machining starts, in-process update with photos at key stages (on request), notification when inspection is complete, and tracking information as soon as the shipment is dispatched.
You will not be waiting and wondering. If something comes up mid-production that affects your order — a material lead time, a process question, a design clarification — we contact you immediately rather than making assumptions.
Send Your Drawing.
Get a Reviewed Quote in 24H —
No Commitment Required
Upload your drawing or STEP file and our engineering team will review it for DFM issues, material suitability, and process fit before sending you a detailed quote. No automated pricing. No sales pressure. Just a clear answer from an engineer.