CNC Machining Services for Custom Parts
XC Machining provides CNC machining services for engineers and product teams across the USA. Upload a CAD file and see your price in minutes. We cut custom CNC parts on our own machines, from one prototype to a full production run. Parts leave the floor in as little as 3 days.
- All uploads are secure and confidential
How CNC Machining Turns a CAD File into Parts
CNC machining services turn a CAD file into a finished part by cutting it from solid metal or plastic. A computer controlled tool removes material until the part matches your design, so the first part and the thousandth part come out the same. XC Machining runs this process for prototypes, low volume runs and production parts. CNC stands for computer numerical control. A programmer turns your 3D model into toolpaths, and the machine follows them in G-code. Because the cutting starts from solid stock, the finished part keeps the strength of the original material. That is the main reason engineers choose machining for load bearing parts, tight fits and parts that need a known material. Most machining falls into two families. In milling, the cutting tool spins and the part stays fixed. In turning, the part spins and the tool stays fixed. Milling makes flat faces, pockets, slots and contoured shapes. Turning makes round parts such as shafts, pins and fittings. Some parts use both.
Our 5-Step Workflow, from CAD Upload to Shipped Part
- Design review. A DFM engineer checks your CAD file for wall thickness, tool access and tolerances.
- Programming. The team builds toolpaths and picks tools and fixtures.
- Cutting. The machine cuts the part from stock, in one setup where the geometry allows.
- Finishing. We deburr the part and apply any finish you chose.
- Inspection and shipping. We measure the part against your drawing, pack it and ship it with tracking.
Our CNC Machining Processes
Our CNC milling services use 3, 4 and 5 axis mills for tight tolerance parts and complex geometry. We cut aluminum, steel, titanium and engineering plastics, hold ±0.005 mm, and reach surface finishes down to Ra 0.8 μm.
Our CNC turning services run multi axis lathes with live tooling for cylindrical, conical and threaded parts. Diameters range from 2 mm to 200 mm (0.08 to 7.9 in) in aluminum, steel, brass, titanium and plastics.
Our CNC routing cuts and engraves sheet stock up to 2400 x 1200 mm (94 x 47 in). It works on aluminum, acrylic, polycarbonate, wood composite and foam, and it suits panels, enclosures and jigs.
On a 5 axis CNC machine the head tilts instead of the part. Undercuts and compound angles come off in one setup, and fewer setups mean tighter accuracy on complex work.
Milling, Turning, Routing and 5 Axis Under One Roof
XC Machining offers four CNC processes. The right one depends on your part shape, size and tolerance.
| Process | Best for | Key spec |
|---|---|---|
| CNC milling | Flat faces, pockets, slots, contoured parts | 3, 4 and 5 axis, ±0.005 mm, finishes to Ra 0.8 μm |
| CNC turning | Round, conical and threaded parts | Diameters 2 mm to 200 mm (0.08 to 7.9 in), live tooling |
| CNC routing | Large sheet parts, panels, enclosures, jigs | Up to 2400 x 1200 mm (94 x 47 in) |
| 5 axis machining | Undercuts and compound angles in one setup | ±0.005 mm, fewer setups |
CNC Machining Tolerances and Part Size Limits
Our precision machining services hold CNC tolerances to ISO 2768 on all metal and plastic parts. For precision work we hold ±0.005 mm (±0.0002 in) on metals and ±0.01 mm on plastics, and we inspect to your drawing and GD&T callouts. We can also hold tolerances tighter than ±0.001 in when the drawing calls for them. GD&T (geometric dimensioning and tolerancing) is the drawing standard that sets how far each feature may vary in form, orientation and position.
| Parameter | Specification |
|---|---|
| Standard tolerance | ISO 2768-m (metals), ISO 2768-c (plastics) |
| Precision tolerance | ±0.005 mm (±0.0002 in) on metals, per your drawing and GD&T |
| Minimum wall thickness | 0.5 mm (0.02 in) |
| Minimum end mill size | 0.5 mm (0.02 in) |
| Minimum drill size | 1 mm (0.04 in) |
| Maximum part size | Milling 4000 x 1500 x 600 mm (157 x 59 x 24 in). Turning 200 x 500 mm (7.9 x 19.7 in) |
| Minimum part size | Milling 5 x 5 x 5 mm (0.2 in cube). Turning 2 x 2 mm (0.08 in) |
| Surface roughness | As machined Ra 3.2 μm. Milled finishes to Ra 0.8 μm. Polished to Ra 0.4 μm |
| Production volume | Prototype 1 to 100. Low volume 101 to 10,000. High volume 10,001+ |
| Lead time | 1 day for simple parts. 5 business days for most projects |
Every tight tolerance adds machining time and inspection time, so apply them only where the part needs them. A CMM measures the critical dimensions before the parts ship. For high precision CNC machining, such as precision machined parts with a tight call on one feature, tell our DFM engineer which feature matters most.
CNC Parts for Aerospace, Medical, Automotive and Robotics
CNC machining makes custom machined parts for aerospace, medical, automotive, robotics and electronics. These are the parts XC Machining makes most:
- Structural housings and enclosures
- Brackets, mounts and bracing
- Production jigs and fixtures
- Bearings, gears and shafts
- Internal mechanical components
- Medical device housings and instruments
CNC Machining vs Casting, 3D Printing and Manual Machining
CNC machining has clear technical and commercial advantages over manual machining, casting and 3D printing for production grade parts.
- Dimensional accuracy within ±0.005 mm (±0.0002 in), repeatable from part to part
- ISO 2768-m standard tolerances on metals
- Production grade aluminum, steel, titanium, brass and plastics
- Prototype parts delivered in 1 to 5 business days
- Lower cost per part at volumes above 100 parts
- Anodizing, plating and powder coating available after machining
CNC machining has limits too. The cutting tool must reach every surface, so deep internal channels and some undercuts are hard or impossible to cut. Complex organic shapes with internal features can cost less to 3D print. Our engineer will tell you when another process fits your part better.
- Dimensional accuracy within ±0.005 mm (±0.0002 in), repeatable from part to part
- ISO 2768-m standard tolerances on metals
- Production grade aluminum, steel, titanium, brass and plastics
- Prototype parts delivered in 1 to 5 business days
- Lower cost per part at volumes above 100 parts
- Anodizing, plating and powder coating available after machining
Quality Control, DFM Support and Machine Capacity
As a CNC machined parts manufacturer, XC Machining runs every project under ISO 9001:2015 certified processes. A DFM engineer stays on the job, and parts get in-process CMM inspection. We hold tolerances from ±0.005 mm with full traceability on every part. Full traceability means a part can be tied back to its material certificate and inspection report.
Our CNC department includes 5 axis milling centers and 3 axis and 4 axis vertical machining centers. It also has turning lathes with live tooling, CNC routers and wire EDM machines. Daily maintenance keeps them at precision standard.
Choose from 60+ machinable materials. They include aluminum 6061 and 7075, stainless 304 and 316, mild steel, tool steel, titanium Grade 2 and 5, brass, copper, PEEK, Delrin, Nylon, ABS and polycarbonate.
Our engineers check every CAD file for wall thickness, draft angles, undercut feasibility and tool access before quoting. You get feedback within 12 hours by email or WhatsApp, at any hour.
Parts are measured on a CMM, and the report ships with the order. Production orders add first article inspection, material certificates and a certificate of conformance with each shipment.
CNC Machining in China, Shipped to the USA
XC Machining runs its CNC shop in Dongguan, China. The shop has 50+ machines, including grinders, wire EDM and automated production lines. We ship by DHL, FedEx or UPS with full tracking and delivery confirmation. Parts go to the USA and to 120+ countries. Our engineers answer by email, WhatsApp or phone, so time zones do not slow a project.
CNC Machining Materials: 12 Metals and Plastics
XC Machining machines 60+ metals and engineering plastics for prototypes and production. CNC machining plastics such as ABS, Nylon, polycarbonate, Delrin and PEEK follows the same process as metals. The table lists the 12 material families customers ask for most. Choose by strength, weight, corrosion resistance, heat and cost.
| Material | Common grades | Yield (MPa) | Tensile (MPa) |
|---|---|---|---|
| Aluminum | 6061-T6, 7075-T6, 2024-T3, 5052-H32, 6082-T6 | 190 to 505 | 230 to 570 |
| Copper | C10100, C10200, C11000, C14500 | 50 to 350 | 200 to 400 |
| Brass | C36000, C26000, C28000, C46400 | 75 to 450 | 300 to 600 |
| Stainless steel | 304, 316, 316L, 303, 17-4 PH | 170 to 1,170 | 485 to 1,310 |
| Carbon steel | 1018, 1045, 1060, 12L14, 1095 | 200 to 900 | 350 to 1,100 |
| Titanium | Grade 2, Grade 5, Grade 23 | 170 to 900 | 240 to 1,000 |
| ABS | General purpose, impact modified, flame retardant | 30 to 50 | 35 to 55 |
| Nylon (PA) | PA6, PA66, PA12, glass filled | 45 to 85 | 50 to 90 |
| Polycarbonate (PC) | General purpose, optical, flame retardant | 55 to 70 | 55 to 75 |
| POM (Delrin) | POM-C, POM-H, Delrin 150, Delrin 500 | 55 to 75 | 60 to 80 |
| PEEK | Unfilled, GF30, CF30, bearing grade | 85 to 110 | 90 to 110 |
| PTFE (Teflon) | Virgin, glass filled, carbon filled, bronze filled | Varies | 20 to 35 |
Aluminum is light, resists corrosion and machines quickly, so parts cost less and ship sooner than steel or titanium. Our aluminum CNC machining service covers aluminum CNC milling and turning, plus aluminum CNC routing for large panels, with 5 axis for complex shapes. We machine housings, brackets, heat sinks, enclosures and precision prototypes.
- Strength range: yield 190 to 505 MPa, tensile 230 to 570 MPa, depending on alloy and temper. Color: silver.
- 6061-T6: the general purpose grade, about 310 MPa tensile, with excellent machinability.
- 7075-T6: the high strength grade, about 503 MPa tensile, for aerospace parts and high load fixtures.
- 2024-T3, 5052-H32 and 6082-T6: available when the application calls for fatigue resistance, sheet forming or structural strength.
- Finishes: as machined, bead blasted, brushed, anodized Type II or III, powder coated, polished or plated.
Our aluminum CNC machining guide helps you pick among the aluminum grades for machining, and our post on CNC aluminum machining tolerances covers the limits. Anodizing adds a thin oxide layer, so tell us whether your drawing size applies before or after anodizing.
Copper has outstanding electrical and thermal conductivity, so it suits CNC machined electrical contacts, heat sinks, busbars and other conductive parts. Its corrosion resistance keeps performance steady in electrical and thermal use.
- Grades: C10100, C10200, C11000, C14500. C110 is 99.9 percent pure copper.
- Strength range: yield 50 to 350 MPa, tensile 200 to 400 MPa. Color: reddish brown.
- Typical parts: electrical contacts, heat sinks, busbars, conductive components.
- Design note: copper is soft and burrs easily, so we deburr every part and check edges before shipping.
Brass machines freely, resists corrosion and conducts electricity. It is a common choice for CNC machined fittings, valves, electrical connectors, threaded components and precision mechanical parts.
- Grades: C36000, C26000, C28000, C46400. C360 is the free machining grade, at about 340 MPa tensile.
- Strength range: yield 75 to 450 MPa, tensile 300 to 600 MPa. Color: golden yellow.
- Typical parts: fittings, valve bodies, connectors, threaded parts.
- Design note: brass cuts cleanly with a fine finish, but it is softer than steel, so it is a poor fit for high load parts.
Stainless steel gives corrosion resistance, strength and durability. We machine it for medical equipment, food processing parts, marine fittings and precision industrial components.
- Grades: 304, 316, 316L, 303 and 17-4 PH. 304 reaches about 515 MPa tensile, and 316L resists chemicals.
- Strength range: yield 170 to 1,170 MPa, tensile 485 to 1,310 MPa. Color: silver gray.
- Typical parts: medical housings, food contact parts, marine fittings, industrial parts.
- Design note: stainless work hardens and wears tools, so it cuts slower than aluminum. Grade 303 machines easier than 304 when corrosion needs allow it.
Carbon steel offers strength, toughness and durability at a lower cost. It is the usual material for CNC machined shafts, brackets, gears and structural parts in automotive and industrial work.
- Grades: 1018, 1045, 1060, 12L14 and 1095. We also machine mild steel 1018, 1045 and A36, and tool steel D2, O1 and H13 for tooling.
- Strength range: yield 200 to 900 MPa, tensile 350 to 1,100 MPa. Color: metallic gray.
- Typical parts: shafts, brackets, gears, structural parts, fixtures and tooling.
- Design note: bare carbon steel rusts, so plan a plating or powder coat for parts that see moisture.
Titanium combines high strength to weight with corrosion resistance and high temperature performance. We machine it for aerospace components, medical device parts and demanding industrial work.
- Grades: Grade 2, Grade 5 (Ti-6Al-4V) and Grade 23 (Ti-6Al-4V ELI). Grade 5 is about 950 MPa tensile and biocompatible.
- Strength range: yield 170 to 900 MPa, tensile 240 to 1,000 MPa. Color: silver gray.
- Typical parts: aerospace brackets, medical device parts, high performance industrial parts.
- Design note: titanium cuts slowly and wears tools, so machine time and cost run above aluminum and steel.
ABS is a tough, light and low cost engineering plastic with good impact resistance. It machines well for prototypes, electronic housings, fixtures and functional plastic parts.
- Grades: general purpose ABS, impact modified ABS and flame retardant ABS.
- Strength range: yield 30 to 50 MPa, tensile 35 to 55 MPa. Colors: black, white, natural.
- Typical parts: prototypes, electronic housings, fixtures, functional parts.
- Design note: ABS softens at lower temperatures than nylon, POM or PEEK, so check service heat first.
Nylon is a durable plastic with strong wear resistance, toughness and low friction. It is common in CNC machined gears, bushings, bearings, rollers and other moving parts.
- Grades: PA6, PA66, PA12 and glass filled nylon.
- Strength range: yield 45 to 85 MPa, tensile 50 to 90 MPa. Colors: natural white, black.
- Typical parts: gears, bushings, bearings, rollers, moving parts.
- Design note: nylon absorbs moisture and its size shifts slightly, so tell us the service conditions when tolerances are tight.
Polycarbonate offers high impact resistance and dimensional stability, and optical grades are transparent. We machine it for protective covers, machine guards, electronic housings and precision plastic parts.
- Grades: general purpose PC, optical grade PC and flame retardant PC.
- Strength range: yield 55 to 70 MPa, tensile 55 to 75 MPa. Colors: transparent, white, black.
- Typical parts: protective covers, machine guards, housings, precision plastic parts.
- Design note: clear parts need a polished finish to stay transparent, and the surface scratches easily.
POM is a high performance plastic known for dimensional stability, low friction and wear resistance. It is a common pick for CNC machined gears, bearings, bushings and precision fittings.
- Grades: POM-C, POM-H, Delrin 150 and Delrin 500.
- Strength range: yield 55 to 75 MPa, tensile 60 to 80 MPa. Colors: natural white, black.
- Typical parts: gears, bearings, bushings, precision fittings, mechanical parts.
- Design note: POM holds tight tolerances more easily than nylon because it takes up less moisture.
PEEK is a high performance thermoplastic with strong heat resistance, chemical stability and mechanical strength. It suits CNC machined aerospace components, medical equipment parts, seals and demanding industrial parts.
- Grades: unfilled PEEK, PEEK GF30, PEEK CF30 and bearing grade PEEK. Service temperature is about 260°C.
- Strength range: yield 85 to 110 MPa, tensile 90 to 110 MPa. Colors: natural beige, black.
- Typical parts: aerospace components, medical equipment parts, seals.
- Design note: PEEK costs far more than other plastics, so use it where heat or chemicals rule the others out.
PTFE has exceptional chemical resistance, very low friction and good thermal stability. We machine it into seals, gaskets, insulating parts, valve seats and sliding components.
- Grades: virgin PTFE, glass filled, carbon filled and bronze filled PTFE.
- Strength range: tensile 20 to 35 MPa. Yield varies by formulation and test method, so XC does not give one figure. Colors: white, black.
- Typical parts: seals, gaskets, insulators, valve seats, sliding parts.
- Design note: PTFE is soft and creeps under load, so tight tolerances are hard to hold.
Our materials page lists the full range of 60+ materials.
Surface Finishes for CNC Machined Parts
We apply these finishes to CNC machined metal and plastic parts for corrosion resistance, wear protection and appearance. Our surface finishing page has the full list.
Sand or bead blasting (Ra 1.6 to 3.2 μm): removes surface marks and gives an even matte texture.
Brushed: a straight satin grain that reduces visible marks.
Anodizing: Type II builds a 5 to 25 μm oxide film with color options. Type III hardcoat builds 25 to 50 μm for wear resistance. Both apply to aluminum.
Powder coating: a durable color coat, 60 to 120 μm thick, for aluminum, steel and stainless steel.
Polishing (Ra 0.05 to 0.4 μm): a mirror finish on aluminum, stainless steel, brass and copper.
Electroplating: nickel, chrome, zinc or gold layers for corrosion resistance, conductivity and hard wear surfaces.
Electroplating deposits nickel, chrome, zinc, or gold layers onto CNC parts for corrosion resistance, conductivity, and hardened wear surfaces.
As machined (Ra 3.2 μm): the fastest and lowest cost option. Tool marks stay visible.
What Design Rules Make CNC Parts Cheaper?
A few design choices decide most of the cost and lead time of a CNC part. Our DFM engineer applies these rules to your CAD file before we quote, and the notes show what to change and why.
| Feature | Guideline | Why it matters |
|---|---|---|
| Wall thickness | Keep walls at 0.5 mm (0.02 in) or thicker. Make tall walls thicker | Thin walls vibrate and warp under the cutter |
| Internal corners | Add a radius larger than the tool radius | A round tool cannot cut a sharp inside corner |
| Small features | Keep pockets and slots wide enough for a 0.5 mm end mill | Smaller tools break easily and cut slowly |
| Holes | Use drill sizes of 1 mm (0.04 in) or larger. Tell us the depth of deep holes | Deep, narrow holes need special tooling |
| Tolerances | Call out tight tolerances only on the features that need them | Every tight call adds machining and inspection time |
| Part size | Milled parts fit within 4000 x 1500 x 600 mm (157 x 59 x 24 in). Turned parts fit within 200 x 500 mm (7.9 x 19.7 in) | Larger parts need a different process |
| Anodized parts | State if the drawing size is before or after anodizing | The oxide layer changes the final dimension slightly |
Want a second opinion before you release a drawing? Send it for a free DFM review, and an engineer replies within 12 hours.
What Materials Does XC Machining CNC Machine?
XC Machining CNC machines 60+ metals and engineering plastics for prototyping and production. Each material is selected for its mechanical properties, machinability, and application requirements. The table below lists our most commonly requested CNC material grades with standard specifications.
6061, 7075, 2024
304, 316, 410, 420
1018, 1045, A36
D2, O1, H13
C360, C464
H59 ,H60
Grade 2, Grade 5 (Ti-6Al-4V)
Our CNC Machining Services Prototype Manufacturing Capabilities
Provides injection molding for prototypes and custom parts, emphasizing expert support, competitive pricing, and faster production cycles.
Get reliable vacuum casting services for high-quality prototypes and production parts at competitive prices. XC Machining offers highly detailed casting parts with consistent quality.
Uses cutting, bending, and forming techniques to produce precision metal components suited for industrial, commercial, and manufacturing applications.
Specialist Industries
Bring Your Designs to Life with XC Machining
Experience precision engineering with XC Machining. From detailed prototypes to high-volume production, we’re here to turn your concepts into reality. Contact us today to discuss your project needs!
- Expertise Shared Widely
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- All uploads are secure and confidential
CNC Machining Services FAQs for Engineers
What are G-code and M-code in CNC machining?
G-code tells the machine how to move. It sets the tool path, the speed of each cut and the position of each axis. M-code controls the machine functions around the cut, such as starting the spindle, turning coolant on and changing tools. A CNC program mixes both. Our programmers build and test them from your CAD model before any cutting starts.
What is a machining center and how does it work?
A machining center is a CNC machine that mills, drills and taps a part in one setup. It changes tools automatically from a magazine and moves along several axes at once. Because the part is not moved between operations, errors from re-fixturing drop out. A 5 axis center can reach most faces of a complex part without reclamping.
Does XC Machining have a minimum order quantity for CNC parts?
No. We machine one prototype or a full production run, and the same team handles both. Small orders get the same DFM review, inspection and quality system as large ones. Our shop handles 1 to 10,000+ parts, so you can start with a single part and reorder as your design and demand grow.
What is the lead time for CNC machined parts?
Our rapid CNC machining ships simple parts in as little as 1 day. Most prototypes ship in about 3 days, and most projects finish in 5 business days. Material, part size, tolerance and finish set the final date. Anodizing, plating and powder coating add time after machining. Your quote shows the ship date for your exact part.
What is the difference between CNC milling and CNC turning?
In CNC milling, the cutting tool spins and the part stays fixed, which suits flat faces, pockets and contoured shapes. In CNC turning, the part spins against a fixed tool, which suits round parts such as shafts and fittings. Parts with both round and flat features run on a lathe with live tooling, so one machine does both jobs.
Which aluminum grade is best for CNC machining?
6061-T6 is the common choice because it machines easily and costs less. Use 7075-T6 when you need higher strength for load bearing parts, since it reaches about 503 MPa tensile against about 310 MPa for 6061-T6. 5052-H32 suits parts that will be bent. Tell our engineer your load, finish and budget, and we will recommend a grade.
What affects the price of CNC machined parts?
Five things set the price: material, machine time, part complexity, tolerance and quantity. Harder metals such as titanium cut slower than aluminum, which raises machine time. Tight tolerances and deep features add setups and inspection. Finishes add a separate step. Larger quantities spread setup cost across more parts, so the cost per part falls.
Which file formats do you accept for a CNC quote?
Upload STEP, IGES, STL or PDF files. STEP files usually give the cleanest and fastest quote because they carry exact geometry. Add a PDF drawing when you have tolerances, threads or finishes to call out. Our DFM engineer reviews the files within 12 hours and flags anything that affects cost or lead time before you approve.
CNC Manufacturing Resources
