Custom Carbon Steel CNC Turning and Milling Parts
Overview
Keyed coupling hubs and carbon steel flanges with side holes often combine turned rotational mating surfaces with milled radial features. XCM CNC provides carbon steel CNC turning and milling for outside diameters, bores, end faces, keyways, flats, side holes and threads, with necessary secondary operations arranged according to drawings. The MOQ is 1 piece. Samples usually take 3-7 days and general orders usually take 10-15 days, depending on complexity and quantity.
Key Capabilities
- Materials: 45#, Q235, 20# carbon steel; grade and material standard per drawing
- Tolerance: +/-0.003 mm (+/-0.00012 inch), IT5 or IT6 accuracy, +/-0.01 mm shaft/bore fits; h6/H7 available
- Surface Finish: Turned outside diameters Ra 0.8 um; finish-milled faces Ra 1.6 um; bored holes Ra 1.6 um
- GD&T: Coaxiality 0.012 mm for rotating features; hole-pattern position 0.015 mm; keyway symmetry 0.02 mm; datums and inspection method defined per drawing
- Max Size: Turning up to diameter 1250 mm x 2000 mm workpiece length; milling machine travel 3000 x 1600 x 1400 mm; combined-part size depends on geometry and setup
- Surface Treatment: Zinc, nickel, or chrome plating 3-20 um; masking and fit allowance per drawing
- Thread: Internal threads from M1.4 and external threads from M2.0; NPT, BSP, G, or PT by specified standard
- Precision Limit: +/-0.003 mm applies only to precision features or small critical dimensions, subject to drawing and inspection review; keyways down to 1.0 mm and turning grooves down to 0.5 mm depend on depth and tool access
Carbon Steel Turning and Milling for Hubs with Flats and Keyways
Coupling hubs typically combine turned outside diameters and bore fits with milled flats or keyways. The keyway transmits torque, while the bore and outside diameter locate the hub relative to the shaft and adjacent parts. Minimum keyway width is 1.0 mm, with feasibility also depending on the keyway standard, depth and inspection method. Keyway symmetry capability is 0.02 mm and requires a defined design datum.
Carbon Steel Flanges with Axial and Radial Datum Relationships
Turning forms flange end faces, locating registers and central rotational features, while milling produces side holes and mounting flats. Hole patterns must relate to the same rotational axis. With defined datums, fixturing and inspection methods, coaxiality can reach 0.012 mm and hole-pattern position 0.015 mm. The Mazak i-100S is a turn-mill center with a second spindle that can perform turning, milling and drilling on the same machine. The turning capacity of diameter 1250 mm x 2000 mm and milling travel of 3000 x 1600 x 1400 mm come from different machines and must not be combined into one machine envelope. Combined-part size depends on geometry and setup.
Carbon Steel Cross-Hole and Thread Finishing for Connectors
Radial holes intersecting axial holes can leave burrs at the intersection, affecting assembly or fluid passages. Side holes can be deburred and specified pipe threads machined. Internal cleanliness standards must be defined in the order, while leak testing is established as a separate requirement.
Carbon Steel Heat Treatment and Plating Across Turned and Milled Features
Heat treatment condition and plating both affect final dimensions of journals, bores, side holes and slots. Drawings must specify heat treatment condition, hardness and whether critical fits are accepted before or after treatment. Plating thickness is 3-20 um. Masking locations and fit allowances for small features such as keyways, side holes and threads depend on the drawing.
Specifications
| Product Name | Custom Carbon Steel CNC Turning and Milling Parts |
|---|---|
| Manufacturer | XCM CNC |
| Factory Location | Shenzhen, Guangdong, China |
| Quality System | ISO 9001, ISO 13485, IATF 16949, GJB9001C |
| Machining Process | CNC turning, milling, drilling, and threading as required |
| Material | Carbon steel |
| Material Grade | 45#, Q235, 20#; verify grade and material standard against drawing |
| Surface Treatment | Zinc, nickel, or chrome plating, 3-20 um; masking and fit allowance per drawing |
| Max Part Size | Turning up to diameter 1250 mm at 2000 mm workpiece length (large lathe); milling workpieces up to approx. 2600 mm long on 3-axis machine depending on fixturing; turn-mill combined parts sized per geometry and setup |
| Inspection | CMM, FAI, and thread-gauge inspection available; report scope per order |
| Application | Coupling hubs, flanged connectors, hydraulic fittings, and machinery interfaces |
| Key Features | Turned bores and outside diameters combined with milled flats, keyways, and radial holes; keyways down to 1.0 mm subject to standard and inspection |
| Critical QC Requirements | Coaxiality 0.012 mm, hole-pattern position 0.015 mm and keyway symmetry 0.02 mm with defined datums; deburring and cleanliness criteria per order |
| MOQ | 1 Piece |
| Typical Lead Time | 10-15 business days after drawing review |
| Drawing Formats | STEP, IGS, DWG, PDF, X_T |
Applications
Keyed Coupling Hubs
A coupling hub mates with a shaft through its central bore and transmits torque through a keyway. Its outside diameter and end faces also locate against adjacent components. Combined turning and milling can produce rotational mating surfaces and side features such as keyways on the same part. Carbon steel suits drive connectors with defined load and wear requirements. The drawing specifies grade and heat treatment condition.
Joint Flanges for Automation Equipment
Robot joint flanges and drive adapters connect reducers, linkages or actuating components. Locating registers, end-face hole patterns and local flats must align with one another. Registers are turned, while hole patterns and flats are milled. A shared drawing datum relates the hole pattern to the rotational axis.
Hydraulic Connectors with Radial Interfaces
A hydraulic line fitting or cylindrical valve body connects to equipment through axial outside diameters or end faces, with radial ports or threaded holes on the sides. Burrs at radial-to-axial hole intersections affect assembly and flow passages. Pipe threads follow NPT, BSP, G or PT standards. Carbon steel is used for hydraulic components whose load and cost requirements suit the material. Media compatibility, sealing arrangements and required tests depend on the specific order.
Cross-Drilled Pin Seats for Construction Machinery
Cross-drilled pin seats and connecting sleeves carry loads or locate through cylindrical surfaces, with transverse holes accommodating pins, oil passages or stops. The orientation and position of transverse holes relative to the central bore determine whether pins install smoothly. Define rotational datums and side-hole locations on the same drawing.
Shaft Supports for Outdoor Tracking Equipment
A shaft support uses a cylindrical bore to support the shaft and side or end-face hole patterns to attach to the frame. A pivot mount adds mounting features outside the rotational locating surface. The relationships between cylindrical datums, hole patterns and faces require coordinated control. Carbon steel suits structural connections focused on load capacity and cost. Outdoor protection requirements must be defined for the project.
Why Choose Us
Quality Systems and Equipment for Combined Features
Our quality systems include ISO 9001, ISO 13485, IATF 16949 and GJB9001C. Equipment includes DMG, Mazak, Matsuura, Brother, Taichung and Qiaofeng, including the Mazak i-100S turn-mill center with a second spindle. These systems and machines support production of carbon steel connectors with rotational mating surfaces and side features.
Turning and Milling Support from Small Connectors to Large Structural Parts
Factory machining coverage extends from small connectors to large structural parts. Turning, milling, drilling, tapping and deburring can be planned around a common drawing datum system. Turned parts can reach diameter 1250 mm x 2000 mm, and milling travel is 3000 x 1600 x 1400 mm. These capacities belong to different machines. Combined-part size depends on geometry and setup.
Equipment Matched to Accuracy, Quality and Cost
In parts such as coupling hubs and flanges, high-precision mating bores and general mounting faces place different demands on machines. Equipment is selected from four tiers from mainland China, Taiwan, Japan, and Europe and the United States according to feature accuracy requirements, balancing machining quality and cost.
Thread and Cross-Hole Acceptance Requirements Agreed in Advance
Pipe threads follow the specified NPT, BSP, G or PT standard and are checked with go/no-go or thread ring gauges. Cross-hole deburring and thread-surface requirements for freedom from crossed or damaged threads, burrs, impact marks and scratches can be included in the order.
First-Article Reports to Verify Combined Interfaces before Production
FAI reports, CMM reports and material certificates can be provided according to the order, with inspection scope agreed for outside diameters, hole patterns, side holes or slot locations. Production follows sample approval so rotational surfaces and side-interface relationships can be verified first.
FAQ
When does a carbon steel part need both turning and milling?
Parts combining coaxial outside diameters or bores with non-rotational features such as keyways, flats or side holes usually require both turning and milling. Define common datums from the drawing first, then plan operations and inspection relationships for each feature.
Can all turned and milled features be completed in one setup?
Not necessarily. The Mazak i-100S with a second spindle performs turning, milling and drilling on the same machine, but fixture obstruction and tool access determine which features can be completed in one setup. Fewer setups help maintain datum consistency. Feasibility depends on the individual part and is evaluated against datums and clamping space.
How are side holes or keyways aligned with the main bore?
The main bore or rotational axis can serve as the locating datum, with side-hole position or keyway orientation defined relative to it and an appropriate inspection method selected. Minimum keyway width is 1.0 mm, with feasibility depending on depth, standard and tool access.
Can you deburr intersecting holes in a steel connector?
Cross-holes can be deburred, with hole-entry, internal-wall burr and cleanliness standards agreed in the order. If pressure or leak testing is required, specify it separately during inquiry so requirements and execution scope can be established.
How do heat treatment and plating affect side holes and keyways?
Both can change the final dimensions of small features, so drawings must clearly state the acceptance condition. Heat treatment changes hardness and may change dimensions. Coatings of 3-20 um reduce bore diameters and increase shaft diameters. Specify whether keyway, side-hole and thread dimensions apply before or after treatment, along with surfaces requiring masking.
What size of turned and milled part can you make?
Distinguish the equipment capacities first. Large-diameter turning supports diameter 1250 mm at a workpiece length of 2000 mm, with diameter 1200 mm as a conservative limit reserving clearance. Three-axis milling travel is 3000 x 1600 x 1400 mm, with workpiece lengths of approximately 2600 mm depending on setup. Combined turned-milled part size depends on geometry and fixturing. For quotation, provide maximum outside diameter, length and side-feature locations.
How are keyways and pipe threads checked on a turned and milled part?
Threads are checked with go/no-go or thread ring gauges selected for the specified NPT, BSP, G or PT standard. Symmetry capability between keyways and the central structure is 0.02 mm. Define design datums first, then establish measurement methods such as CMM inspection. Thread-surface requirements for freedom from crossed or damaged threads, burrs and scratches can be included in the order.
What information should I provide to quote a turned and milled part?
Provide 2D/3D drawings, the material grade and standard, quantity, tolerances, intended use and critical requirements. Identify primary datums, side-hole or keyway relationships, heat treatment, surface treatment and inspection requirements. Supported formats include STEP, IGES, STP, DWG and dimensioned PDF.
Request a CNC Machining Quote from XCM CNC
Send us your drawings. Our team will review the file and reply with a machining quote. MOQ: 1 piece, with competitive low-cost pricing.
