FREQUENTLY ASKED QUESTIONS

CNC Machining FAQ — Answers Before You Ask

Everything overseas engineering buyers want to know before sending CAD files: tolerance, materials, lead time, DFM, MOQ, QC, NDA and global shipping. Can't find your answer? Email us — an engineer replies within one business day.

±0.005 mm Tolerance 24h Quote & Free DFM ISO 9001:2015 IATF 16949 NDA Protected

How fast can I get a quote?

We send a detailed quotation within 24 hours after receiving your CAD files and requirements. For urgent parts, upload STEP/IGES/DWG and mention "rush quote" — we often respond within a few hours on business days.

Do you offer free DFM (Design for Manufacturability) review?

Yes. Every RFQ goes through a free DFM review by our engineers before quoting — we flag tight tolerances, problematic internal corners, wall thickness and cost-saving opportunities, so you get a part that is both machinable and cost-effective.

What file formats do you accept?

We accept STEP, IGES, DWG, DXF, SolidWorks (SLDPRT/SLDASM), Parasolid and PDF. Please send 3D CAD plus a 2D drawing with dimensions, tolerances and material called out when possible.

What is your MOQ?

There is no minimum order quantity. We start from a single prototype, run low-volume bridge production, and scale up to 100,000+ mass-production parts — all under the same QC system.

What machining tolerance can you hold?

Our stable production tolerance is ±0.005 mm on critical features (tightest on CNC milling and turning), with CMM inspection for precision parts. Typical commercial tolerance is ±0.02–0.05 mm at a lower cost.

Are you ISO 9001 and IATF 16949 certified?

Yes. Rejin CNC runs under ISO 9001:2015 and IATF 16949 quality management systems, with incoming material inspection, in-process QC and final CMM / optical inspection before every shipment.

Do you provide inspection reports?

Yes. We provide First Article Inspection (FAI) reports, dimensional reports and CMM reports on request — included for precision and regulated-industry parts, sent as PDF with the shipment.

Can you do 5-axis CNC machining?

Yes. We run 3-axis, 4-axis and 5-axis simultaneous machining for complex geometries such as impellers, thin-wall housings, deep cavities and aerospace components that cannot be fixtured in one setup on a 3-axis mill.

What materials can you machine?

We machine 10+ materials: aluminum 6061 / 7075 / 6063, stainless steel 303 / 304 / 316 / 17-4PH, brass C360, copper, mild steel 1045 / 4140, titanium Gr.5, POM (Delrin), PEEK, PMMA and engineering plastics. Mill Cert / EN 10204 3.1 available.

What surface finishes do you offer?

Anodizing (Type II & Type III hard-coat), bead blasting, powder coating, passivation, electropolishing, nickel / chrome / zinc plating, chemical film (Alodine), polishing and laser marking — handled in-house or by approved partner shops, color-matched to your spec.

Can you machine parts for audio, 3C and heat-sink industries?

Yes — audio interface panels, mic bodies, DAC enclosures, 3C structural parts, knobs/fasteners and custom heat sinks are our strongest product lines, with experience in tight cosmetic anodizing and precise heat-sink fin geometry.

How do you ship internationally?

We ship worldwide by DHL, FedEx and UPS express (3–5 days) for samples and small orders, and by sea / LCL for bulk production. DDP shipping to the US, EU and most countries is available on request — duties handled upfront.

What payment terms do you accept?

We accept T/T (bank transfer), PayPal and credit card for small orders; for larger production orders, 50% deposit + 50% before shipment, with L/C acceptable for high-volume contracts.

Do you sign an NDA?

Yes — we are used to protecting customer designs. We will sign your NDA before any CAD file is shared, and your drawings, models and part designs are never reused for other customers.

Can I visit your factory?

Absolutely. Our factory is in Dalang Town, Dongguan, Guangdong, China — about 40 minutes from Shenzhen Bao\u2019an airport and 1 hour from Guangzhou. Factory audits, sample handover and engineering review meetings are welcome.

Still have a question about your project?

Send us your drawings and requirements — a senior CNC engineer replies within one business day with a free DFM review and a detailed quote.

Fill in the form below and get your quote within 24 hours.

SIMPLE PROCESS

What Happens After You Click Send?

Inquiry Received

Your message lands directly with our senior engineers — instantly acknowledged.

Engineer Review

We study your requirements and propose a workable solution with material & process options.

Quote Within 24h

Detailed quotation with specs, options and lead time — no hidden fees.

Sample & Production

Approve the sample, then we mass-produce with full QC and on-time shipping.

WhatsApp: +86 13790500374

Email: info@rejincnc.com

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