Fraisage CNC Milling Service from China

French-speaking engineers searching for a milling supplier often use the term fraisage cnc rather than "CNC milling", and the search results they get are a mix of French job shops, machine tool builders and Asian contract manufacturers. For a buyer in Lyon, Montreal or Casablanca comparing quotes from Europe and China, the technical conversation is the same in both languages, but the paperwork is not.

This guide covers what actually changes when a fraisage cnc order crosses a language border: how drawings are interpreted, which material grades are equivalent, where tolerance defaults differ, and what documentation a Chinese supplier should be able to provide without a follow-up email.

What Fraisage CNC Covers

Fraisage is milling — a rotating multi-tooth cutter removing material while the workpiece is held stationary on a table. CNC milling covers three families of work that are quoted very differently:

3-axis milling

The tool approaches from one direction. Prismatic parts, plates, brackets, flanges, pockets and slots are all 3-axis work. It is the cheapest form of fraisage cnc per part because setup is simple and the machine can run unattended once the program is proven.

4-axis and 5-axis milling

A fourth axis adds rotation about one axis, which allows holes and faces on four sides of a part to be cut in one clamping. A fifth axis adds a second rotary axis, which allows undercut contours, impeller blades and ports at compound angles. Five-axis work is not automatically more accurate; it removes setups, and removing setups is what removes position error between features.

Mill-turn

A turn-mill centre combines a lathe spindle with milling capability, which suits parts that are mostly rotational but carry cross holes, flats or milled slots. For a motor housing or a valve body, mill-turn can replace two machines and one re-chuck.

Drawing Conventions That Cause Rework

A French drawing and a Chinese process sheet do not always describe the same thing, and the gap is usually in the general tolerance note rather than in a dimension.

French drawing term	English equivalent	What the shop needs to know
Tolérance générale	General tolerance	Which standard: ISO 2768-m, -f or -c
État de surface Ra	Surface roughness	Value in µm, and whether it applies to all faces
Chanfrein	Chamfer	Size and angle, or "casse-arête" only
Rayon de raccordement	Fillet radius	Whether it is a design or a tool radius
Plan de référence	Datum	Which face establishes A, B, C
Traitement de surface	Surface treatment	Anodizing, passivation, plating, and thickness
Marquage	Marking	Laser, stamp or label, and content

The most common rework trigger is a drawing with ISO 2768-m as the general note and no indication of which faces are functional. A shop that mills everything to ±0.1 mm will quote high; a shop that mills everything to ±0.5 mm will deliver parts that do not assemble. Marking the functional faces, the datums and the fits resolves the ambiguity before the quote.

Material equivalents

Grade names differ between EN, AISI and GB standards. A Chinese shop will buy to the GB or EN grade, so the drawing should state the standard and, where the application is critical, the mechanical property rather than only the name.

French / EN designation	US equivalent	Typical use in milled parts
S235JR	A36	Weldments, brackets, non-critical plates
C45 / 1.1191	1045	Shafts, keys, general mechanical parts
42CrMo4 / 1.7225	4140	High-strength parts, hydraulic components
25CrMo4	4130	Tube and ring parts, moderate strength
X5CrNi18-10 / 1.4301	304	General stainless, food and clean environments
X5CrNiMo17-12-2 / 1.4404	316L	Marine, chemical, medical
6082-T6	6061-T6 (close)	Structural aluminum parts, housings
2017A / 2024	2017 / 2024	High-strength aluminum, aerospace pattern work
CuZn39Pb3	360 brass	Fittings, connectors, valve bodies

If the drawing calls for 1.4301 and the part is destined for a food line, the equivalent to confirm is not the name but the certificate: an EN 10204 3.1 mill certificate naming the heat number is the document that survives an audit. Chuangling buys to the standard named on the drawing and attaches that certificate to the inspection pack.

Tolerance and Finish: What Milling Can Hold

Injection Molding Machine Parts

A milling machine can hold much tighter tolerances than a general tolerance note implies, but the cost curve is not linear. The table below shows what is routine, what needs a second operation, and what needs grinding instead.

Requirement	Routine milling	Needs care	Better done by grinding
Linear tolerance	±0.1 mm	±0.02 mm	—
Hole position	±0.05 mm	±0.02 mm	—
Hole diameter	H7 with reaming	H6 with fine boring	—
Flatness over 200 mm	0.05 mm	0.02 mm	0.01 mm
Parallelism between faces	0.05 mm	0.02 mm	0.005 mm
Surface finish	Ra 3.2 µm	Ra 1.6 µm	Ra 0.4 µm and below
Hardness above 45 HRC	Not practical	—	Required

A common mistake in fraisage cnc enquiries is asking for Ra 0.8 µm on a large face. That finish on a milled surface usually means a finishing pass with a small step-over, which multiplies cycle time, or a subsequent grinding operation. If the function only needs a sealing surface, specify flatness and Ra 1.6 µm and let the shop choose the method.

Fixtures, Deburring and the Hidden Cost Drivers

Three items drive the price of a milled part more than the material does.

Fixtures. A part with no natural clamping face needs soft jaws, a dedicated fixture or a vacuum plate. For a first article that is a one-time cost; for a repeat order it is amortized. Ask whether the fixture is included in the tooling cost or charged per batch.

Deburring. Milled edges carry burrs, and burrs on a part that will be handled in assembly are a quality escape waiting to happen. Hand deburring is cheap per part and inconsistent across a batch; vibratory finishing is consistent but changes edge geometry. Specify which edges matter.

Setup count. Each additional clamping adds position error and labour. A part designed with one datum face and features reachable from two directions costs less than the same part requiring four setups, even when the machining time is identical. Chuangling reviews the setup count at quotation stage and flags the parts where a small design change would remove one clamping.

Documentation to Ask For

For a first order, the package that prevents disputes is short: a dimensional report on the marked critical dimensions, a material certificate with the heat number, a surface treatment certificate where applicable, and photographs of the finished batch before packing. For regulated industries, add a first article inspection report to AS9102 or PPAP format, and a control plan for the critical features.

Chuangling issues inspection reports against the drawing revision and keeps the revision on the job card, which matters when a customer sends a revised drawing mid-batch.

How to Run the First Order

Send the 3D model, the 2D drawing with datums and general tolerance marked, the material standard, the surface treatment, the annual quantity and the required delivery. Ask for a process route with the number of setups and the inspection plan, not only a price.

Chuangling quotes fraisage cnc work from 3-axis milling through 5-axis and mill-turn, with turning, grinding, casting and forging available in the same plant, so a part that needs a milled face and a ground bore does not have to travel between suppliers. For French-speaking buyers, drawings in French are read directly and quoted back with the English process notes attached, which keeps the technical record in one language for the customer's own quality file.