We machine 303, 304, 316L, 420 and 17-4PH into seals, housings and valve bodies. 16 five-axis centers, ±0.005 mm tolerance and a 4,000 mm size ceiling. Send a drawing and get a quote with DFM notes in 12 hours.
The alloy is not hard to cut. It is hard to cut without moving, loading up or burning a tool.
303 and 304 work-harden fast. Heavy clamping and dull inserts push the wall out of true, so a 1.5 mm web that measured on the machine ends up 0.06 mm off after the vise opens. We rough, stress-relieve, then finish with light passes and low clamping force.
Austenitic grades weld to the tool edge under heat. A tapped M6 hole in 316L can come out with torn crests and a gauge that will not pass. We cut threads with form taps or single-point tools at controlled speed, and check with go/no-go gauges.
This grade machines in the annealed state and then ages to H900 or H1075. If the shop skips the shrink allowance, holes and bores close up after heat treat. We machine to pre-age dimensions and confirm hardness and size after aging.
A seal groove at Ra 0.4 μm is a functional requirement, not a finish note. If the surface is left at Ra 3.2 μm, the O-ring leaks and the whole assembly fails leak test. We inspect the groove surface and report the measured value.
Stable setups, correct inserts, and inspection that matches the drawing callout.
Stainless steel cnc machining rewards stiffness over speed. We keep tool overhang short, use balanced holders and run carbide grades made for austenitic and PH grades. Coolant goes to the cutting edge, not over the part.
For parts with thin floors or long bores, we add support between operations instead of adding passes. That keeps the geometry you modeled.
Every re-clamp adds error. Our 16 simultaneous 5-axis centers and 16 mill-turn centers cut ports, flanges and angled holes in a single setup. True position holds because the datum never moves.
For long shafts and manifolds, the 4,000 mm travel machine handles parts that would otherwise need splicing or welding.
The same part behaves differently in each grade. This is what we see on the floor.
| Grade | Typical Use | Machining Notes |
|---|---|---|
| 303 | Shafts, fittings, bushings | Free-machining; best surface finish |
| 304 / 304L | Housings, brackets, tanks | Work-hardens; light finishing passes |
| 316 / 316L | Medical, marine, food contact | Galls easily; form taps preferred |
| 420 / 440C | Wear parts, valve seats, knives | Heat treat after machining |
| 17-4PH | Aerospace, pump shafts | Machine oversize, then age |
| 430 / 431 | Decorative and mild corrosion | Magnetic; good for shafts |
One shop for machining, finishing and inspection.
Complex stainless geometry cut in one setup. Best for valve bodies and impellers with angled ports.
Plate work, housings and brackets. Good fit for flat parts with drilled patterns.
Shafts, fittings and bushings. Turned and milled in a single cycle.
One-off stainless prototypes for fit checks before tooling spend.
Passivation, bead blasting, polishing and plating matched to the grade.
Dimensional reports and material certs on request with the shipment.
Use this to judge whether your part is a fit before you send it.
| Machine Type | Travel or Size | Typical Parts |
|---|---|---|
| 5-axis centers | Up to 750 × 1,150 × 550 mm | Valve bodies, impellers |
| Large travel mill | 4,000 × 400 × 150 mm | Long shafts, manifolds |
| Compact 3-axis | 500 × 500 × 450 mm | Plates, small housings |
| Mill-turn centers | Ø400 mm rotary table | Fittings, bushings, shafts |
| Tolerance | ±0.005 mm | Seal grooves, bearing bores |
| Finish range | Ra 0.2–3.2 μm | From as-machined to fine |
Founded in 2011. Three wholly-owned plants and 150 technicians across Dongguan and Singapore.
Enough spindle capacity to run prototypes and production without pushing your job to the back.
Quotation plus free DFM analysis. Production can start within 24 hours of approval.
From one prototype to 10,000+ part runs. Same process, same inspection.
Raw material check, in-process monitoring and final inspection on every lot.
ISO 9001:2015, IATF 16949:2016, ISO 13485:2016 and ISO 27001:2022.
316L bodies with clean bores and no trapped chips.
17-4PH parts machined oversize, then aged to final size.
Seal grooves held to finish, not just to size.
316L parts finished for washdown and chloride exposure.
Start with the environment, not the machinability. Chlorides or washdown push you to 316L. A shaft running in a bushing usually wants 303 for finish, or 17-4PH if you need strength after aging.
If corrosion is mild and cost matters, 430 or 431 machines well. We will tell you when a grade change is worth it and when it is not.
Yes, on features that allow it. A bearing bore in a rigid housing is a normal job at that tolerance.
A long unsupported wall will move no matter who cuts it. We flag those features in the DFM review and propose a workable tolerance instead of promising one we cannot hold.
We machine in the annealed condition, leaving an allowance for the size change that comes with aging. Then the lot goes to H900 or H1075 as your drawing calls out.
After aging we check hardness and critical dimensions. If a bore closed up, we catch it before shipment, not at your assembly line.
Ra 0.2–0.8 μm is achievable on turned and milled surfaces with the right tool and pass. As-machined work typically sits at Ra 1.6–3.2 μm.
Tell us the function of the surface. A groove that seals needs a finish callout. A bracket face usually does not, and paying for it is wasted money.
Yes. Passivation removes free iron left by cutting tools and restores corrosion resistance on 300-series grades.
We also offer bead blasting, polishing and plating. Pick the finish based on where the part lives, not on how it looks in a photo.
There is none. One prototype and a 10,000-part run go through the same setup and inspection process.
Small runs are useful for proving a design. When the design is stable, we scale the same program rather than rewriting it.
Quotation and free DFM analysis come back within 12 hours. Production can start within 24 hours of approval, and parts ship in 3–5 days for standard jobs.
Complex geometry or outside finishing adds time. We tell you the real date up front rather than revising it later.
Uploads are secure and confidential. We sign an NDA on request before reviewing drawings.
Our quality systems include ISO 27001:2022 for information security, so file handling follows a documented process.
Upload your STEP file and tolerances. We reply with a quote, a DFM review and a machining plan within 12 hours.
12-hour quote100% inspectionNo minimum orderNDA on request
Trusted by engineers and manufacturers worldwide
Upload your 3D model or 2D drawing and get a quotation with a free DFM analysis. Maximum processing size 4,000 mm.
CNC Metals 13 grades
CNC Plastics 10 grades
Machines & processes 12 options
Surface & post-processing 10 options
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