Servicio de fresado CNC China

Axis count should match part geometry, tolerance requirements, and setup economics.

3-axis milling handles 80% of machined parts. If your part has features on one or two faces, 3-axis is the cost leader. The trade-off is that parts with features on three or more faces need multiple setups, which adds labor and introduces setup error.

4-axis milling adds a rotary A-axis, letting the cutter reach three or four faces in one setup. Specify 4-axis when you have pockets, holes, or slots on multiple sides and positional tolerance between them matters.

5-axis milling adds continuous B and C axes, so the cutter tilts and rotates during the cut. Required for parts with undercuts, compound curves, or angled features that 3-axis and 4-axis setups cannot reach. 5-axis also reduces setup count to one, which cuts cumulative positional error on precision parts.

5-axis is more expensive per hour but cheaper per part when it eliminates refixturing. Our engineering team can recommend the right axis count during the DFM review.

Milling and turning are complementary processes that together cover most subtractive machining.

Milling holds the workpiece stationary and rotates the cutting tool. Best for parts with prismatic geometry: flat faces, pockets, slots, and complex 3D surfaces. Vertical and horizontal machining centers are the standard platforms.

Turning rotates the workpiece against a stationary tool. Best for cylindrical parts: shafts, bushings, rods, and threaded components. Lathes and Swiss-type lathes are the standard platforms.

Many production parts use both. A shaft with a keyway is turned for the cylindrical diameter, then milled for the keyway. Our factory runs both processes on coordinated cells, so hybrid parts stay on the same traveler through finishing.

CNC milling covers the widest material range of any subtractive process.

Aluminum alloys (6061, 7075, 2024, 6063, 5052) are the default for aerospace, electronics, and consumer parts. Machines at 300 to 600 m/min with carbide tools.

Steel alloys (304, 316, 416 stainless; 4140, 4340 tool steels; 1018, 1045, Q235 structural) cover strength, corrosion, and hardness requirements. Work hardening on 316 stainless requires controlled feed rates.

Specialty metals include titanium Grade 5 (Ti-6Al-4V), brass C36000, copper C11000, and nickel superalloys (Inconel 718, Monel 400). Titanium and nickel alloys require slower cutting speeds and specialized tooling due to low thermal conductivity.

Engineering plastics include PEEK, POM (Delrin), Nylon, PC, ABS, PMMA, PVC, and PP. Plastics need controlled feeds to avoid melting from heat buildup.

Material selection should match the part’s mechanical load, operating environment, and cost target. Our DFM review can recommend the best grade before programming starts.

Tolerance depends on machine class, tool selection, and whether the part is post-machined or ground.

General tolerances hold ±0.1 mm on features up to 50 mm and ±0.2% of feature size on larger dimensions. This covers most commercial parts.

Tight tolerances hold ±0.05 mm typical and ±0.02 mm on 5-axis programs with precision-ground tooling and thermally controlled machines. Our linear interferometer calibration delivers ±0.005 mm per 300 mm of travel.

Surface finish ranges from 3.2 μm Ra (standard roughing and finishing tool paths) down to 0.8 μm Ra (precision finishing with smaller step-overs and controlled feeds). Mirror finish below 0.4 μm requires a secondary polishing pass.

Flag critical dimensions on your drawing so they can be reviewed for achievable tolerance before programming starts. Over-tolerancing every dimension drives up cost without improving part performance.

Our work envelope caps at 2,000 × 1,000 × 1,000 mm on the largest gantry-style vertical machining centers. Larger parts can be split and joined if the application allows.

Mid-size parts up to 1,000 × 600 × 500 mm run on production VMCs with 40-taper spindles. This is where most commercial milling programs land.

Small precision parts under 200 × 200 × 100 mm run on high-speed spindles at 12,000 to 20,000 RPM for fine-feature work on aluminum and brass.

5-axis envelopes are typically smaller than 3-axis due to the B and C axis mechanisms, but the largest 5-axis centers in our cell handle 800 × 800 × 600 mm with full simultaneous motion.

CNC milling wins on tolerance, surface finish, and material strength. 3D printing wins on complex internal geometries and low volumes.

Choose CNC milling when tolerance below ±0.1 mm is required, surface finish below 3.2 μm Ra is needed on large areas, or the material must be a wrought grade (6061 aluminum, 304 stainless, Ti6Al4V bar stock) whose mechanical properties differ from the 3D-printable version.

Choose 3D printing when the part has internal channels, lattice structures, or organic geometries that CNC cannot reach, or when volume is 1 to 10 parts and setup and programming costs dominate.

Many programs use hybrid manufacturing: 3D print the complex base geometry, then CNC mill the critical mating features. Our engineering team can recommend the right split during DFM review.

Yes. Most production programs include at least one post-machining operation.

Anodizing is standard on aluminum parts for corrosion and wear resistance. Type II anodizing adds 5 to 25 μm; Type III hardcoat adds 25 to 75 μm for abrasion-heavy applications.

Powder coating is standard on steel parts for outdoor or high-salt environments. Powder coat delivers 500 to 1,000 hours of salt spray resistance in 60 to 120 μm coatings.

Passivation is required on stainless steel medical and food-grade parts to remove free iron and restore the chromium oxide layer (ASTM A967).

Electroplating adds bright chrome, nickel, zinc, or tin for cosmetic and functional finishes on steel and brass. Plating adds 5 to 30 μm to part dimensions.

Polishing to Ra 0.2 to 0.8 μm is available for optical surfaces, sealing faces, and mirror finishes. Specify on the drawing which surfaces require polishing since it is a manual operation.

Decide on finish requirements during the DFM review because they often influence material selection and dimensional tolerance.

Custom fastener production covers a range of processes that convert wire or bar stock into finished parts. Here are the primary processes available through most full-service fastener manufacturers.

1. Cold Heading: Progressive dies form the head, shank, and recesses from a wire blank. The most cost-effective process for volumes above 10,000 pieces. Diameter range 1.5 to 25 mm.

2. CNC Turning: Rotating bar stock is machined by cutting tools. Suitable for fasteners with complex geometries, unusual thread forms, or tolerances tighter than cold heading allows.

3. Swiss Machining: A variant of CNC turning for small-diameter, long, or precision parts. Used for miniature fasteners and medical screws with tolerances to ±0.01 mm.

4. Thread Rolling: Hardened dies form threads by cold displacement rather than cutting. Rolled threads are stronger than cut threads and produce no chips. Standard process for high-strength fasteners.

5. Tratamiento térmico: Quenching, tempering, carburizing, or induction hardening produces fasteners to specified strength grades (Grade 5, 8, Class 8.8, 10.9, 12.9).

6. Plating and Coating: Zinc, hot-dip galvanizing, electroless nickel, black oxide, Dacromet, and chrome plating applied after threading. Provides corrosion resistance and appearance.

7. Inspection and Testing: Dimensional inspection with CMM and thread gauges. Mechanical testing includes tensile, hardness, and torque-tension. Salt spray testing for plated fasteners.

A full-service manufacturer combines these processes under one roof, reducing lead times and eliminating the coordination overhead of managing multiple suppliers.