CNC Machining in the USA

Why US engineering teams offshore precision machining

The math is straightforward for most US engineering teams: a custom machined part that costs $120–$180 in small-batch domestic production frequently lands at $35–$60 from our shop, including shipping and import duties. For prototype runs of 1–50 pieces the difference is smaller but still real; for production runs of 500+ pieces it is typically 40–60% total landed cost. That is why US companies in automation, robotics, medical devices and defence regularly send drawings to Xi'an.

But price is only half the story. The other half is whether the supplier can hold the tolerance, deliver the paperwork, and answer a technical question at 3 a.m. Central Time. We have built the operation around those three things: 40+ CNC machines, in-house CMM inspection with NIST-traceable calibration, and engineers who respond to RFQs with a DFM review instead of a price list.

What US buyers should know about lead times

From the moment we receive your CAD and drawing package, the typical timeline is: engineering review and quote within 24 hours; sample or prototype parts in 10–15 working days for aluminum and stainless; production orders in 3–5 weeks depending on complexity and surface finishing; and then 3–5 business days in transit to the US via FedEx International Priority or DHL Express.

The fastest way to compress that schedule is a complete package: STEP file, PDF drawing with GD&T called out, material grade, quantity, and your target unit price. Incomplete packages are the number-one source of quote delays — we would rather ask twice than guess wrong on a ±0.01 mm bore.

Tolerances, materials and finishes US customers actually order

Standard machining tolerance on our mills and lathes is ±0.05 mm. We routinely hold ±0.01 mm on critical features, and with grinding or honing we can reach ±0.005 mm on diameters. The most common specification we see from US customers is ISO 2768-m general tolerance with specific GD&T callouts on mating surfaces — that is exactly the combination our process is built for.

By material, the order books run: 6061-T6 and 7075-T6 aluminum (roughly half of what we cut), 304/316 stainless, 4140/4340 steel, titanium 6Al-4V, Inconel 718, and engineering plastics including PEEK and acetal. Surface finishes ordered most often are as-machined (Ra 1.6), Ra 0.8 for sealing surfaces, clear or black anodize on aluminum, and passivation on stainless for medical and food-contact work.

Quality systems and paperwork

We ship every production order with a material certificate and dimensional inspection report. In-house we run Zeiss and Mitutoyo CMMs with NIST-traceable calibration, and we can provide full FAIR (First Article Inspection Report) per AS9102 when the order requires it. Our quality system is certified to ISO 9001:2015; AS9100D and IATF 16949 work is handled under those management frameworks and we support PPAP Level 3 documentation for automotive customers.

For defence and ITAR-scoped work: controlled data stays on physically isolated servers, access is limited to trained staff, and transfers are logged. Scope and procedure can be verified under NDA before any drawing is shared.

Shipping, duties and payment

We ship weekly consolidated air freight to the US, with individual express shipments for urgent orders. Transit is 3–5 business days door-to-door, and we handle export documentation (commercial invoice, packing list, and when required, certificate of origin). Import duties to the US are typically 0–7.5% depending on HTS classification — we quote on EXW or FOB Xi'an basis and can also quote DDP (delivered duty paid) so the landed cost is fixed before you approve.

Standard payment terms for US customers are T/T 30% deposit with the balance before shipment, or PayPal for prototype orders under $500. For repeat customers with approved credit history we can discuss net terms on production orders.

Working across time zones

Xi'an is 12–14 hours ahead of US time zones depending on the season. In practice this works in your favor: send a drawing late Friday afternoon US time and our engineering team picks it up Monday morning Xi'an time — your Monday morning, which means a quote is often waiting in your inbox by Tuesday. Our project managers answer email around the clock and schedule calls to overlap with US business hours when needed.