Machine Acceptance in China Before Shipment: FAT Checklist, Test Parts, and Video Report

Introduction

The machine has arrived at your facility. It's been unloaded, installed, connected, and started up for the first time — and within hours, it's clear: something is wrong. The spindle hums louder than it should, the guideways move in fits and starts, the tool changer keeps making errors, and the first test part fails to meet the specified tolerances.

You send a claim to the manufacturer. The response is a standard line: "It worked perfectly at our factory. The problem likely occurred during transport, installation, or operation."

And here's where the real conflict begins.

Without a proper  machine acceptance inspection in China , proving the defect existed before shipment is extremely difficult.

A video from the supplier showing the machine "gliding smoothly along its axes" is not technical evidence.

A photo of the CNC screen turned on is not evidence either.

Even a demo run on an aluminum blank tells you nothing about how the machine will perform with your steel, your cutting parameters, and your tolerances.

Based on technical supervision experience, a significant share of claims against Chinese machines could have been prevented at the FAT stage — Factory Acceptance Test. This is not a formal walkthrough, not a factory tour, and not a friendly meeting with the supplier's manager. FAT for a machine from China is an engineering procedure that verifies geometry, positioning, spindle, CNC, hydraulics, pneumatics, electrical systems, test machining, documentation, and packaging.

The main goal of FAT is not to "find a reason to fight with the factory" but to document the machine's actual condition before packaging and shipment. While the equipment is still at the manufacturer's site, the buyer has leverage: you can demand adjustments, component replacement, re-testing, payment withholding, or refusal to ship. Once the container is sent, that leverage drops sharply.

In this article, we'll cover how a proper pre-shipment machine inspection should be conducted, which tests you can't skip, how to choose a test part, what a video report should include, and which documents you need before signing the acceptance certificate.

What Is FAT and Why You Can't Release Final Payment Without It

Factory Acceptance Test is acceptance testing of equipment at the manufacturer's facility before packaging and shipment. In the context of buying a Chinese machine, FAT ensures the equipment matches the technical specification, contract, and stated parameters.

Simply put, FAT answers four questions:

1. Is this the exact machine that will be shipped to the buyer?
2. Does it match the ordered configuration?
3. Does it hold the stated accuracy?
4. Can you sign the acceptance certificate and authorize shipment?

Without FAT, the buyer takes on the risk of a pig in a poke. The manufacturer may be reputable, but even good factories have assembly errors, incorrect settings, substituted components, weak packaging, missing documents, or unresolved issues from internal QC.

Why FAT Has Legal Weight

A signed FAT protocol is a document that can serve as the basis for further actions:

• accept the machine without remarks;
• accept the machine with a list of required fixes;
• withhold final payment;
• demand re-inspection;
• refuse shipment until defects are resolved;
• file a claim if a post-delivery issue matches a remark from FAT.

It's important to understand: if FAT wasn't specified in the contract, the supplier may try to reduce the inspection to a simple demonstration. So ideally, the acceptance procedure should be defined in advance: which tests are performed, which instruments are used, who signs the protocol, which parameters are acceptable, and what happens in case of non-conformance.

What FAT Delivers in Practice

A thorough machine acceptance test verifies:

• geometry of working components;
• positioning accuracy and repeatability;
• spindle runout;
• stability across different speeds;
• CNC functionality;
• automatic tool change;
• hydraulics, pneumatics, and coolant;
• electrical cabinet, grounding, and safety;
• actual configuration;
• documentation and packaging.

For machines priced from 30,000 USD, FAT should already be a mandatory procedure. For CNC machines, heavy machines, gantry centers, boring mills, turn-mill complexes, and equipment for serial production, FAT isn't just desirable — it's critically necessary.

When FAT Is Mandatory

FAT Checklist: 10 Essential Items

Below is a baseline CNC machine acceptance checklist that you can adapt for lathes, milling machines, gantry centers, boring mills, and machining centers.

1. Verify Configuration Against Specs Before Powering On

The first thing to do at FAT is not to start the machine but to cross-check it against the contract, specification, and technical requirements. If you start with a demo, you might miss the big picture: the machine may be assembled with a different configuration than what you paid for.

Check:

• machine model;
• machine serial number;
• spindle serial number;
• CNC model and number;
• servo motors and drives;
• guideways;
• ball screws;
• tool changer;
• coolant pump;
• hydraulic power unit;
• pneumatic system;
• electrical cabinet;
• additional options;
• tooling package;
• spare parts kit;
• documentation.

Pay special attention to nameplates. If the specification lists HIWIN or THK guideways, NSK or SKF bearings, or a Fanuc or Siemens system, this must be confirmed not by the manager's word but by clear photos and videos showing the markings.

What to Capture in Photos and Video

If the factory won't let you photograph nameplates or says "that's not necessary," that's a red flag. A reputable manufacturer understands that a pre-shipment machine inspection includes component verification.

2. Geometric Tests

Geometric inspection of a machine from China is one of the key FAT stages. Geometry determines whether the machine will consistently hold dimensions, flatness, perpendicularity, and concentricity.

The inspection must follow a clear methodology, not guesswork. International practice uses ISO 230-1. In Russian and post-Soviet engineering tradition, methods close to GOST 8 and the manufacturer's specifications for a specific machine type may apply.

Check:

• straightness of travel along X, Y, Z axes;
• perpendicularity of axes;
• parallelism of table travel;
• spindle concentricity;
• spindle runout;
• table flatness;
• guideway parallelism;
• relative positioning of working components.

Minimum Instrument Set

Reference Control Parameters

Important: you can't assess geometry in a cold shop in winter or a hot shop in summer without recording temperature. Metal expands, and measurement results may be inaccurate. If the temperature deviates from normal, it must be noted in the protocol.

3. Positioning and Repeatability Testing

Machine positioning repeatability testing is a separate FAT block that can't be replaced by "running a program." Just because the machine moves smoothly along its axes doesn't mean it returns to the exact same point accurately.

A proper check requires a laser interferometer. An indicator can help with basic diagnostics, but it doesn't replace measurement along the full axis length.

How the Test Is Conducted

For each axis, a series of movements is performed:

• at least 10 cycles;
• at different points in the work envelope;
• with deviation recording;
• with graph plotting;
• with temperature noted;
• with feed rate noted;
• signed by the responsible person.

Bad practice: testing only the center of the work envelope. On many machines, it's the edges of the machining zone that reveal real problems: geometry drop-off, backlash, ball screw error, thermal expansion, or insufficient compensation.

What the Protocol Must Include

If the supplier says "you don't need an interferometer," look at the machine class and part requirements. For rough machining, a basic check may suffice. But for precision housing parts, fits, molds, hydraulic components, aerospace or energy components — FAT without an interferometer will be incomplete.

4. Test Machining: A Control Part Instead of a Demo

Test parts for a CNC machine are the most honest way to verify how the equipment performs in real work. But only on one condition: the part must be yours or as close as possible to your production tasks.

The factory often offers to machine its own demo part. Usually it's chosen so the machine looks good: soft material, convenient geometry, gentle parameters, simple dimensions, no critical fits.

That's not FAT. That's a presentation.

What Part You Need

The test part should include:

• face milling;
• contour milling;
• drilling;
• boring;
• threading;
• pockets;
• internal and external corners;
• surfaces with roughness requirements;
• holes with tight tolerances;
• features that test concentricity and perpendicularity.

The material must be real. If you'll be machining 1045 steel, stainless steel, cast iron, or heat-resistant alloy, you can't accept the machine based on an aluminum blank. Aluminum produces a pretty picture but won't reveal the machine's rigidity, spindle stability, or behavior under load.

Example Test Part for a Milling Center

How to Measure the Part

Calipers are only good for rough checks. For a real FAT, you need:

• micrometer;
• bore gauge;
• dial indicator;
• surface profilometer;
• coordinate measuring machine (CMM);
• measurement report for each critical dimension.

Control machining on a CNC machine must be captured on video: blank loading, clamping, program start, machining, part removal, measurement. If the supplier only shows a finished part on the table — that's not proof.

5. Spindle Inspection

The spindle is one of the most expensive and critical components. An error here can lead to vibration, poor surface finish, accelerated tool wear, part defects, and costly repairs.

What to Check

1. Spindle runout
   Check with a high-precision indicator. For most machining centers, a good target is up to 0.005 mm. For higher-precision work, requirements may be tighter.
2. Heating
   The spindle must run at various speeds for at least 1–2 hours, not just a few minutes. Housing temperature is recorded with a thermocouple or thermal imager. If the housing noticeably overheats within a short time, that's a risk of bearing, lubrication, or assembly issues.
3. Noise
   A sound level meter isn't just a formality. Uneven sound, humming, howling, or metallic overtones may indicate bearing or balancing problems.
4. Vibration
   At high speeds, the machine shouldn't "sing," shake, or transmit vibration to the frame.
5. Acceleration and deceleration
   Test all stated speed ranges: low, medium, maximum.
6. Automatic tool change
   If the machine has an ATC, run a series of tool changes. Not one or two — at least 20–30 cycles. Check time, grip accuracy, absence of impacts, and sensor correctness.

Spindle Inspection Table

6. CNC System Inspection

The CNC system is the machine's brain. Even if the mechanics are well-assembled, poor CNC setup can create problems in real operation.

Check:

• brand and model match the specification;
• interface language;
• parameter accessibility;
• axis correctness;
• manual mode operation;
• automatic mode operation;
• loading your control program;
• drilling, boring, and threading cycles;
• tool compensation;
• interpolation;
• alarm messages;
• parameter backup.

You can't accept a machine based only on the manufacturer's demo program. At FAT, you need to load your program or specially prepared test code. If the machine must work with a specific CAM system, verify post-processor compatibility.

What You Must Take With You

• CNC parameter backup;
• alarm code list;
• parameter recovery instructions;
• electrical diagram;
• servo drive data;
• password or access procedure for service settings, if provided in the contract.

If CNC parameters aren't saved, recovery after a failure, battery replacement, or operator error can take weeks.

7. Hydraulics, Pneumatics, and Coolant Inspection

Hydraulics and pneumatics rarely look impressive on video, but they're often the cause of problems after startup.

Check:

• system pressure;
• pressure stability;
• absence of leaks;
• pump operation;
• hose condition;
• fitting quality;
• cylinder operation;
• chuck clamp/unclamp;
• air blow-off operation;
• coolant supply system;
• filtration;
• presence of magnetic inserts and filters.

Pay special attention to connection points. Oil seepage, weak fittings, sloppy hose routing, and missing labels are signs of poor assembly culture.

Minimum Check

8. Electrical and Safety Inspection

The electrical cabinet is a place you absolutely must look inside. A nice exterior doesn't guarantee clean electrical assembly.

Check:

• diagram matches actual wiring;
• wire labeling;
• terminal quality;
• grounding;
• fan operation;
• cabinet air conditioner, if equipped;
• emergency stop;
• limit switches;
• door interlocks;
• indicator lights;
• safety sensors;
• overload protection.

Ground resistance should be tested with an instrument. Target: no more than 4 ohms unless otherwise specified by site requirements and local codes.

You must test the emergency stop button. Not visually — actually: the machine must stop dangerous motion, the system must produce a correct signal, and restart must only be possible after a proper alarm reset.

9. Packaging and Marking Inspection

Many buyers mistakenly think FAT ends after the test part is machined. No. Until the machine is properly packed, the risk remains.

Bad packaging can destroy a good machine.

Check:

• wooden crate or metal frame;
• moisture barrier film;
• silica gel;
• anti-corrosion treatment;
• securing of moving components;
• machine fastening to the base;
• guideway protection;
• electrical cabinet protection;
• center of gravity marking;
• "do not tip," "fragile," "keep dry" signs;
• packing list;
• photos before closing the crate;
• photos after closing the crate.

For heavy machines, gantry centers, and long equipment, packaging must be discussed in advance. If the machine ships by sea, moisture protection is critical. If the shipment is oversized, verify the fastening and loading plan in advance.

10. Documentation Inspection

Documents aren't a secondary item. Without them, you can face problems during installation, operation, service, customs, and warranty disputes.

Required Documents

If the manual in English isn't ready yet, at least get the English version before shipment. Translation can be refined later, but electrical diagrams, hydraulic schematics, CNC parameters, and the FAT protocol must be in the buyer's hands before the machine ships.

Test Part: How to Choose and What to Check

A test part for a milling center or lathe should be diagnostic, not pretty. Its job is to expose the machine's weak points.

Selection Criteria

The part should:

• replicate your actual production task;
• include critical operations;
• contain dimensions with tolerances;
• test geometry;
• test machining stability;
• be made from your material;
• be measured with proper instruments.

If you're buying a machine for housing parts, the test part should include surfaces, holes, pockets, boring, threads, and datum features. If it's a lathe — external turning, internal boring, grooves, threads, facing, runout and concentricity checks.

What to Measure

The Biggest Mistake

The biggest mistake is accepting a machine based on one part made under ideal conditions, at the manufacturer's parameters, from convenient material, and measured with calipers.

Proper FAT requires: your part, your material, your parameters, your measurement, your protocol.

Video Report: Can You Trust Remote Acceptance?