Custom Online CNC Machining Services
CNC machining cuts solid metal or plastic blocks into finished parts using rotating tools. Holds ±0.01mm （Full Tolerance Standard）on critical features and ISO 2768-m as standard elsewhere, runs from 1 prototype to 10,000+ production parts on the same machine. The default process for functional parts in aluminum, stainless, brass, POM, and any other material where tolerance and strength matter. For design best practices, see our CNC DFM Guidelines
CNC Machining Capabilities
| Feature | Description |
| Maximum Part Size | CNC Milling: 4000×1500×600mm／ CNC Turning: Ø200×500mm |
| General Tolerances | Metals: ISO 2768-m (±0.05–0.5mm), ISO 2768-f on request Plastics: ISO 2768-c standard |
| Precision Tolerances | Down to ±0.01mm on critical features |
| Standard Lead Time | 5 business days (simple parts 1–3 days) |
| Machines | 3-, 4- & 5-axis CNC Milling, CNC Turning, EDM, Swiss Machining |
| Post-Processing | Surface Finishing |
| Type | Material | Service | Process | More Info |
|---|---|---|---|---|
| ABS | ABS | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| PC | PC | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| PC-ABS | PC-ABS | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| PMMA / Acrylic | PMMA | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| POM / Acetal | POM (Delrin) | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Nylon / PA | PA6 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Nylon / PA | PA66 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Glass-Filled Nylon / PA | PA6-GF30 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Glass-Filled PBT | PBT-GF30 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| PTFE / Teflon | Teflon | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| PEEK | PEEK | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Glass-Filled PEEK | PEEK-GF30 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Bakelite / Phenolic | Bakelite | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Type | Material | Service | Process | More Info |
|---|---|---|---|---|
| Aluminum | 2024 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Aluminum | 5052 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Aluminum | 5083 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Aluminum | 6061-T6 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Aluminum | 6063 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Aluminum | 7075-T6 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Aluminum | ADC12 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Magnesium | AZ31B | CNC Machining | CNC Milling | Data Sheet |
| Magnesium | AZ91D | CNC Machining | CNC Milling | Data Sheet |
| Stainless Steel | SUS304 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Stainless Steel | SUS316 | CNC Machining | CNC Milling | Data Sheet | Selection Logic |
| Carbon Steel | 45# / AISI 1045 | CNC Machining | CNC Milling | Data Sheet |
| Carbon Steel | Q235 / ASTM A36 | CNC Machining | CNC Milling | Data Sheet |
| Alloy Steel | 40Cr / AISI 4140 | CNC Machining | CNC Milling | Data Sheet |
| Brass | H62 / C360 | CNC Machining | CNC Milling | Data Sheet |
| Copper | T2 / C110 | CNC Machining | CNC Milling | Data Sheet |
| Type | Material | Service | Process | More Info |
|---|---|---|---|---|
| Foam | Foam | CNC Machining | CNC Milling | Data Sheet |
(Coming Soon)
Materials Supported
Common Metal Materials
Aluminum machines fast and cleanly, cutting speeds 3–5× faster than steel, longer tool life on cheap inserts. 6061 is the default for brackets, housings, and structural parts. 6082 is the European equivalent with similar properties. 7075 runs harder and stronger but costs 3× more; reserved for aerospace structural parts and components under sustained load. 2024 for parts that need fatigue resistance. All aluminum grades anodize, with 6061 and 6063 taking color most evenly.
Stainless steel machines slower than aluminum but holds tighter tolerances on small features. 304 is the general-purpose grade, food contact, light corrosion, decorative parts. 316 adds molybdenum for saltwater and chemical environments. 303 has added sulfur for easier machining but lower corrosion resistance, used on free-cutting turned parts. 17-4 PH for parts that need high strength and corrosion resistance after heat treatment.
Carbon steel is the cheapest option and the strongest at the same hardness range. 1018 mild steel for structural brackets and weldments. 1045 medium-carbon for shafts, gears, and parts needing some hardness. 4140 alloy steel for high-strength structural parts, often heat-treated to HRC 28–32 after machining. All carbon steel grades rust without surface protection, zinc plating, black oxide, or powder coat after machining
Brass machines faster than any other common metal and produces clean chip evacuation. C360 free-cutting brass is the standard grade for fittings, valves, and threaded components. C260 cartridge brass for parts needing more cold-working before final machining. Brass holds a polished finish on its own without coating, common on decorative hardware and electrical connectors.
Copper machines softer than brass and tends to drag on the cutter, sharp tools and high feed rates work better than slow careful cuts. C110 pure copper for electrical bus bars, grounding straps, and heat sinks. C145 tellurium copper machines better but loses some conductivity. C932 bearing bronze for bushings and wear surfaces. Copper parts often require chemical passivation or tin plating to prevent surface oxidation.
Common Plastic Materials
POM holds dimensions during and after machining better than any other engineering plastic, minimal stress relief needed. Low coefficient of friction makes it the go-to for gears, bushings, and sliding parts. Drills clean, taps clean threads. Black POM resists UV slightly better than natural white. Avoid POM on parts that see acids or strong oxidizers.
Nylon machines tougher than POM but absorbs moisture, parts grow 0.5–1% in humid conditions, which shifts dimensions on tight-tolerance features. Condition stock material before final passes, or hold critical dimensions with post-conditioning machining. MC901 cast nylon machines more stably than extruded nylon. Used for wear pads, structural pulleys, and impact-resistant brackets.
ABS is softer than POM or nylon, easier to scratch and dent during fixturing. Machine with sharp tools, light cuts, and air blast for chip clearance (no flood coolant; coolant absorbs into the surface). Used for prototype housings and parts that will be glued, vapor-smoothed, or painted. Not for load-bearing applications or parts running at temperatures above 80°C.
PC is harder to machine than ABS, cracks easily at sharp internal corners and shows stress lines along tool paths. Slow feed rates, sharp single-flute cutters, and minimal heat buildup. Don’t use chlorinated coolants; PC stress-cracks on contact. Common for clear prototype lenses, structural panels, and impact-resistant covers.
Material Selection Guidance
Material choice on CNC parts usually comes down to one question: what does the part have to survive in service? Aluminum 6061 covers 60% of jobs, strong enough, light, cheap, anodizes well. Stainless steel 304 for corrosive environments or food contact. Brass and copper for electrical or fluid applications. POM for plastic wear parts; PC and ABS for cosmetic prototypes.
Material affects machining cost more than most designers expect. A part in 7075 aluminum costs 2× the same part in 6061. A part in stainless 316 costs 3–4× the same part in 304. PEEK plastic costs 10× POM. Worth it only when the application actually demands the upgrade, otherwise it’s money cut into chips.
Tolerances & Precision
Tight tolerances drive CNC cost faster than any other factor. ±0.2mm is standard on most features. ±0.05mm requires a slower second pass and post-machining inspection. ±0.01mm requires controlled machining and full dimensional inspection. Anything tighter than ±0.005mm moves to grinding or hand finishing. Call out tight tolerances only on features that actually need them, mating bores, bearing fits, threaded holes. Everything else stays at general machining tolerance.
Ready to Quote Your CNC Parts?
Upload your CAD files and drawings for a manufacturability review and CNC machining quote. Share your material, quantity, and tolerance requirements to help our team review your project.
- CAD files and drawings
- Manufacturability review
- Prototype and production inquiries
| General Tolerances | Metals: ISO 2768-m. ±0.1mm up to 6mm, ±0.2mm from 6 to 30mm, ±0.3mm from 30 to 120mm, ±0.5mm from 120 to 400mm. ISO 2768-f available on request. Plastics: ISO 2768-c. ±0.2mm up to 3mm, ±0.3mm from 3 to 6mm, ±0.5mm from 6 to 30mm, ±0.8mm from 30 to 120mm. |
| Precision Tolerances | Tolerances down to ±0.01mm with controlled machining and post-process inspection. Tighter than ±0.005mm requires grinding or hand finishing |
| Min Wall Thickness | Metals: 0.5mm Plastics: 1.0mm. Thinner walls deflect under cutting force. |
| Min End Mill Size | 0.5mm. Smaller cutters break under standard feed rates |
| Min Drill Size | 1mm standard. 0.3mm achievable on dedicated micro-drilling setups at higher cost. |
| Maximum Part Size | CNC Milling: 4000×1500×600mm CNC Turning: Ø200×500mm |
| Minimum Part Size | CNC Milling: 5×5×5mm CNC Turning: Ø2×2mm |
| Production Volume | Prototyping: 1–100 pcs Low volume: 101–10,000 pcs High volume: 10,000+ pcs |
| Lead Time | 5 business days for most projects. Simple parts ship in 1–3 days |
Surface Finishing Options
As Machined
Standard CNC finish with surface roughness Ra 1.6–3.2μm typical, up to Ra 6.3μm on deep pockets and long-reach features. Visible tool marks on flat surfaces and faint helical lines on bored holes. Sharp edges are broken to 0.3–0.5mm.
Bead Blasting
Glass beads or aluminum oxide media blasted onto the surface under pressure. Removes tool marks and creates a uniform matte texture. Standard pre-anodizing treatment for aluminum parts, since bead-blasted surfaces hold anodize color more evenly than as-machined finishes.
Brushing
Abrasive belt drawn across the surface in one direction, producing a linear grain pattern at Ra 0.4–0.8μm. Commonly applied to stainless steel panels, aluminum trim, and decorative parts. Grit 120–240 produces the standard #4 architectural finish used in most builds.
Anodizing
Electrochemical process for aluminum only. Type II builds a 5–25μm color layer for decoration and basic corrosion protection, available in black, clear, red, blue, and gold. Type III hard anodize builds a 25–75μm wear-resistant layer in gray or black. Mask threads and bearing surfaces.
Design Guidelines
A part can be drawable in CAD and still take 4 hours per piece to machine. Good CNC design means tools can reach all features in 1–2 setups, walls are thick enough to hold under cutting force, and internal corners match standard tool diameters. Cuts cycle time more than picking a cheaper material does
| Core DFM Principles | Better DFM for CNC machining usually means: – practical wall thickness – reasonable hole size and hole depth – internal corner radii that match cutting-tool reality – controlled cavity depth – realistic thread depth – tight tolerances only where function requires them |
| Wall Thickness | The document uses these practical starting points: – Metals: around 0.8 mm – Plastics: around 1.5 mm – For some turned features, 0.5 mm / 0.020 in is treated as a lower threshold in many cases. |
| Holes and Hole Depth | Small holes and deep holes are common machining cost drivers. The design guidance recommends keeping holes as large as function allows and keeping drill-based hole depth around 4× diameter when possible, while noting that deeper drilling up to 12× diameter may be possible in more aggressive cases but becomes more process-sensitive. Blind holes should also include extra depth to account for drill tip shape and tool clearance. |
| Internal Corners and Tool Radius | CNC milling cutters are round, perfectly sharp internal corners aren’t possible. Standard practice: internal corner radius of 1.5–3mm matches common end mill sizes (Ø3, Ø6 cutters). Forcing a 0.5mm radius means switching to a smaller cutter, which slows the job and costs more. If a mating square feature needs clearance, add a relief slot or dog-bone cut at the corner instead of forcing a sharp internal corner. |
| Threads | The guidance emphasizes that threads are easy to over-design. Standard thread sizes should be used where possible, and thread engagement of roughly 1×D to 2×D is often enough for many applications. Deeper threads usually add tapping difficulty and cycle time without delivering useful additional strength. |
| Deep Cavities and Long-Reach Features | Deep cavities are among the most common DFM problems. The recommendation is to keep cavity or pocket depth within about 4× tool width where possible, because long-reach tools reduce stiffness and increase chatter, deflection, and surface-finish problems. |
| Avoid Unnecessary Precision | Specifying ±0.025mm on a cosmetic face that only needs to look flat doubles inspection time and triples scrap risk. Mark critical dimensions on the drawing with tight tolerances; leave the rest at general machining tolerance. A good drawing tells the machinist which faces are functional and which are decorative. |
Typical Applications
Concept Models
A CNC machined concept model helps teams review part geometry against engineering drawings. Use it during prototype development to check form, accessible features, and design changes before production.
Functional Prototypes
CNC prototyping produces functional aluminum housing parts for checking mounting features and component interfaces. Prototype manufacturing in the intended material helps engineers identify changes before a production run.
Engineering Validation
Dimensional inspection compares CNC machined features with the drawing. These measurements support design verification of critical dimensions before assembly or further production.
Fit & Assembly Testing
Fit testing checks how a mating pin enters a machined bore. A trial mechanical assembly can reveal alignment, insertion, or clearance issues before parts are ordered in larger quantities.
Market Testing Samples
Small batches of near-final CNC machined product samples give customers physical parts for product evaluation, fit checks, and feedback before broader product testing or launch decisions.
Bridge Production
Low volume manufacturing keeps CNC machined parts available while production plans and bridge tooling are finalized. Repeatable small batches help teams move from prototype to production.
Equipment & Capacity
Our CNC machining services cover milling, turning, multi-axis machining, and selected EDM and Swiss machining requirements. The right process depends on part geometry, tool access, material, tolerances, and production quantity. Share your drawings so the manufacturing route and inspection needs can be reviewed together.
3-Axis CNC Machining
3-axis CNC machining suits plates, brackets, pockets, and other parts with features accessible from straightforward tool directions. Additional setups may be needed to reach opposing faces or side features.
4-Axis CNC Machining
4-axis CNC machining adds rotary positioning for parts that need machining around several sides. It can reduce manual repositioning for shafts, housings, and components with features at different angles.
5-Axis CNC Machining
5-axis machining helps reach angled surfaces and complex geometry with fewer fixture changes. Access, workholding, and the required machining strategy are reviewed for each part.
CNC Turning
CNC turning is generally suited to rotational parts such as shafts, bushings, pins, and sleeves. Features including shoulders, grooves, bores, and threads determine the tooling and inspection plan.
EDM
Electrical discharge machining is considered for conductive materials and features that are difficult to cut with conventional tools. Wire EDM and sinker EDM serve different geometries and require separate process reviews.
Swiss Machining
Swiss machining is suited to selected small-diameter, slender turned parts where supporting the stock close to the cutting area helps control deflection. Part length, diameter, features, and batch size determine suitability.
Quality Control Flow
View our ISO 9001:2015 Certificate →
Incoming Inspection
Incoming quality control starts with the purchase order and material certificate. We check the specified alloy, temper, stock dimensions and material identification before machining. Any mismatch needs review before the material is released to production.
In-Process Inspection
First article inspection checks the initial part against the drawing before a production run continues. In process inspection then focuses on critical dimensions, workholding and changes that could affect part consistency. Tool wear or a setup change may call for another check.
Final Inspection
Finished parts are checked against the drawing for specified dimensions, hole locations and mating features. CMM inspection and suitable hand gauges support dimensional checks. Inspectors also look for burrs, damaged edges and surface defects before release.
Documentation and Traceability
Material certificates, job records and inspection results connect the finished part to its production lot. This supports material traceability when dimensions or material identity need to be checked later. Request a first article inspection report with your RFQ if the project requires one.
CNC Machining: Common Questions
What CAD files and drawings are needed for a CNC machining quote?
A STEP (.stp or .step) model is preferred for a CNC machining quote. We can also review IGES, Parasolid (.x_t), and PDF or DXF drawings where appropriate. Include a 2D drawing for critical dimensions, GD&T, threads, fits, and surface finish requirements. If you only have a STEP file, send it for an initial review and identify any features that require special control.
What tolerances can you achieve for CNC machined parts?
General dimensional tolerances can be specified using ISO 2768-1, where appropriate. Tighter tolerances may be feasible on selected features, but depend on part size, material, geometry, setup, and inspection method. State critical dimensions, datums, and required fits on your drawing; we review them before confirming the machining approach.
How much does CNC machining cost?
CNC machining cost depends mainly on material, part geometry, setup count, machining time, tolerances, finishing, and quantity. A deep pocket, difficult tool access, or a tightly controlled feature can increase cost. Upload your CAD file and drawing with the required quantity to receive a project-specific quote.
Is there a minimum order quantity for CNC machining?
We can review requests for a single prototype as well as low volume manufacturing and repeat production. The practical order quantity and unit price depend on the part and production setup. If you are comparing quantities, include the target volumes in your RFQ so we can evaluate pricing options.
What affects CNC machining lead time?
Material availability, part complexity, required setups, quantity, tight tolerances, finishing, and inspection requirements all affect CNC machining lead time. We confirm the production schedule after reviewing the drawing and order details. Tell us your required delivery date when requesting a quote.
What metals and plastics can you CNC machine?
Common CNC machining materials include aluminum alloys, stainless and alloy steels, brass, copper, titanium, and engineering plastics such as POM, PEEK, PC, ABS, PA6, and PA66. Provide the exact material grade and condition, especially where strength, heat treatment, moisture sensitivity, or certification matters. We confirm material availability and machinability for each project.
What surface finishes are available for CNC machined parts?
Options include as-machined surfaces and, where suitable for the material and application, bead blasting, anodizing, powder coating, plating, passivation, or polishing. Finish selection can affect dimensions, appearance, and corrosion performance. Add the required coating specification, appearance requirement, or surface roughness to your drawing for review.
Can you sign an NDA before reviewing our CAD files?
Yes. If your project requires a confidentiality agreement, send the NDA request to [email protected] before sharing controlled design files. We can review the agreement and coordinate the appropriate file submission process.
Can you provide First Article Inspection and CMM reports?
First Article Inspection (FAI), CMM dimensional reports, material certificates, and other inspection documents can be reviewed as part of the RFQ. Specify the required standard, drawing revision, dimensions, sampling plan, and report format before ordering. We confirm which documents and inspection methods are available for your project.
Ready to Quote Your CNC Prototype?
Upload your STEP file and get a DFM review + quote within 12 hours. No tooling cost. Minimum 1 part.
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