Precision CNC Turning · Dongguan, CHINA
CNC Turning Services for High-Concentricity Turned Parts
Swiss-style and turn-mill CNC turning for shafts, connectors,
bushings, and rotational parts - held to ±0.005 mm and finished to Ra 0.2 µm,
with material certs and inspection data on every order.
AS9100D ISO 13485 30 yrs experience 52 countries served No MOQ
Upload Drawing - Free DFM ReviewGet a Quote in 12 Hours
30 Years machining turned parts
120,000+ Turned shafts shipped last year
280 Active shaft part numbers
0 ppm Thread-integrity field failures
Turning Cell - Live
| Tightest tolerance | ±0.005 mm |
| Best surface finish | Ra 0.2 µm |
| L : D ratio (slender shafts) | up to 20:1 |
| Turned shafts shipped / yr | 120,000+ |
| Quote turnaround | 12 hrs |
Turning is the right call when the part is round
CNC turning rotates the workpiece against a single-point tool that moves along the X and Z axes - the most efficient, most repeatable way to make cylindrical and rotational features. We have run turned work for three decades, and the parts that land on our lathes are rarely simple: long slender shafts that must stay coaxial within microns, multi-step connectors, hardened pins, and threaded bodies where the fiftieth piece has to fit exactly like the first.
Two things decide whether a turned part succeeds - holding concentricity as the tool travels down the length, and keeping threads and mating diameters in tolerance batch after batch. Our process is built around both: Swiss-style sliding-headstock lathes for deflection-free slender work, Doosan turn-mill centers that finish multi-feature parts complete in one setup, and CMM verification of runout and fit on every first article. That is the difference between a quote and a part that ships.
Capabilities at a glance
CNC Turning Specifications
The working envelope and process limits our turning cell holds in production. Values marked for confirmation are machine-specific - replace them with your verified shop figures before publishing.
| Turning processes | Swiss-style (sliding headstock) · CNC turn-mill (live tooling + sub-spindle) · chucker / bar-fed lathe |
| Max bar capacity (Swiss) | Ø65mm |
| Max swing / chuck dia. | Ø300mm |
| Max turning length | 510mm |
| Live tooling / C-axis / sub-spindle | Yes - driven tools, C-axis, second spindle for back-working |
| Tightest tolerance | ±0.005 mm on critical features · ±0.001 mm micro-precision |
| Surface finish | down to Ra 0.2 µm off the lathe (no secondary polishing) |
| Concentricity / runout | held within 3 μm · L:D ratio up to 15:1 |
| Spindle speed | up to 6000 rpm |
| Bar feed / lights-out | automatic bar feeders · unattended runs for free-machining materials |
| Volume range | 1-piece prototype → 50,000+ production · no MOQ |
| Inspection | Mitutoyo CMM · optical comparator · profilometer · thread plug/ring gauges |
Tolerance, finish, concentricity, and volume figures above are MID's published capability. Bar capacity, swing, length, and spindle speed depend on the exact lathes in your cell - verify and fill these in.
In-house operations
Turning operations we run every day
Most turned parts are finished complete in one or two setups - we keep the full operation set under one roof rather than shipping work out mid-process.
OD & ID turning
Outer and inner diameters, bores, and counterbores to print.
Facing
Flat, square end faces and shoulders as a datum reference.
Taper & profile
Conical, curved, and contoured rotational surfaces.
Grooving & parting
O-ring grooves, retaining-ring slots, clean cut-off.
Single-point threading
Low-volume and large-diameter threads on the lathe.
Thread milling & rolling
Hardened-material threads; rolled threads for fatigue life.
Drilling & boring
Axial holes, deep bores, and precise ID sizing.
Live-tool milling
Flats, slots, cross-holes and hex without a second setup.
Knurling
Straight, diamond, and grip knurls for handles and inserts.
Splining
Drive splines and serrations on shafts and couplers.
Back-working
Sub-spindle pick-off finishes both ends in one cycle.
Deburring & passivation
Edge-break and ASTM A967 passivation in-house.
Material drives the cut - and we know the cut
Each family below behaves differently on the lathe. The note on each is the real machining behavior we plan around, not a spec-sheet line.
Inspection data ships with the part, not as an add-on
Industries we supply
The documentation and tolerance discipline carry across every sector - qualify us once, use us for all of it.
Reasons buyers move their turned work to us
From drawing to turned parts in four steps
Send your drawing
Upload 2D/3D CAD (STEP, IGES, PDF, DWG) through the encrypted portal. Mutual NDA signed within one business hour.
Tolerance & DFM review
Our engineers confirm tolerances, material, and finish, and flag any feature that adds cost without function.
Fast quote
You get an itemized quote - machining, finishing, inspection, shipping - within 12 business hours.
Production & inspection
Parts are turned, inspected on the CMM, documented, and shipped with certs and FAI where required.
CNC turning FAQ
Q: What tolerances can you hold on CNC turned parts?
A: We hold ±0.005 mm on critical turned features as standard, and ±0.001 mm on micro-precision details under controlled conditions. Concentricity and total runout on shafts are verified to within microns on a Mitutoyo CMM, and the readings are documented per order so you can audit them against the print.
Q: Do you offer Swiss-style turning for long, slender shafts?
A: Yes. Long, slender shafts run on Swiss-style sliding-headstock lathes, where the guide bushing supports the bar millimetres from the cutting point and eliminates deflection. We routinely turn length-to-diameter ratios up to 20:1 while keeping the part coaxial within microns end to end.
Q: What is your maximum bar diameter and turning length?
A: Our Swiss cells handle bar stock up to Øconfirm: 300 mm, and chucker/turn-mill work runs to roughly Øconfirm: 65 mm swing and confirm: 510 mm length. If your part is close to those limits, send the drawing and we will confirm fit on the exact machine before quoting.
Q: What surface finishes can you achieve without secondary polishing?
A: On suitable materials we reach Ra 0.2 µm directly off the lathe, no separate polishing step. When a part needs more, bead blasting, passivation per ASTM A967, anodizing, and electroplating are available as finishing options and are coordinated as part of the same order.
Q: Can you finish multi-feature parts complete in one setup?
A: Yes. Parts with both turned and milled features move to Doosan turn-mill centers with live tooling and a sub-spindle, which turn, drill, cross-mill, and thread in a single setup. Machining complete in one setup removes re-fixturing error and protects the concentricity between turned and milled features.
Q: Is there a minimum order quantity for turned parts?
A: No. We produce one-piece prototypes, small R&D batches, and full production runs without penalty setup fees on low volume. The same process documentation and the same project manager carry from prototype into production, so you never re-qualify the supplier when volume ramps.
Q: How do you verify thread integrity and mating fit?
A: Threads are cut by single-point threading, thread milling, or thread rolling depending on volume and material, then verified with plug or ring gauges (UN, UNJ, UNF, metric M, NPT, BSPP, BSPT, or custom). Mating fit is confirmed by physically assembling the first article as a matched set, not by inspecting pieces in isolation.
Q: What documentation ships with my turned parts?
A: Every order can include mill-heat-traceable material certs, CMM dimensional reports, profilometer finish readings, and thread-gauge results. AS9102 First Article Inspection reports and ASTM A967 passivation certificates are provided where the application requires them.
Send a drawing - get a turning quote in 12 hours
Upload your STEP, IGES, PDF, or DWG file. We sign a mutual NDA within one business hour and return an itemized quote with DFM feedback the same business day or the next.