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Custom Online CNC Machining Services
nstant quotes on custom metal and plastic machined parts | Quick turn prototypes and production parts in days | Free standard shipping on all US orders | International prototype pricing includes tariffs | ISO 9001:2015, ISO 13485, IATF 16949:2016, AS9100D certified. ITAR registered.
Why Use Unofactory for Custom Online CNC Machining Services?
Unofactory provides a custom online CNC machining service to engineers, product developers, designers, and more through our vetted network of 10,000+ suppliers. Our highly qualified and certified machine shops can make any custom design, simple or complex. We offer rapid machining, small-batch machining, and high-volume production, with all orders serviced by Unofactory from end to end. Upload a CAD file to the Unofactory Instant Quoting Engine® to get a price, lead time, and design-for-manufacturability feedback on your custom CNC parts. Our fast CNC machining capabilities include services for metals and plastics and flexible production and shipping options to meet you at the perfect price and product development stage. Your price for CNC-machined prototypes includes tariffs and shipping for standard parcels.
Unofactory assures the quality of your machined parts with our ISO 9001:2015, ISO 13485, IATF 16949:2016, and AS9100D certified quality management system, ITAR registration, and options to add inspections, hardware traceability, material certifications, and CoCs. We accept technical drawings and have support teams to ensure you get quality CNC-machined parts on time.
What is CNC Machining?
CNC, or computer numerical control machining, is a widely used manufacturing process that uses automated, high-speed cutting tools to form designs from metal or plastic stock. Standard CNC machines include 3-axis, 4-axis, and 5-axis milling machines, lathes, and routers. Machines may vary in how CNC machined parts are cut—the workpiece may remain in place while the tool moves, the tool may remain in place while the workpiece is rotated and moved, or both the cutting tool and workpiece may move together.
Skilled machinists operate a CNC machine by programming tool paths based on the geometry of the final machined parts. The part geometry information is provided by a CAD (computer-aided design) model. CNC machines can cut almost any metal alloy and rigid plastic with high precision and repeatability, making custom CNC machined parts suitable for nearly every industry, including aerospace, medical, robotics, electronics, and industrial. Unofactory provides CNC services and offers custom CNC quotes on over 40 materials ranging from commodity aluminum and acetal to advanced titanium and engineered plastics like PEEK and Teflon.
Custom CNC Machining Services: Machining, Turning, Milling, and Routing
Custom CNC Milling Services
CNC Turning Service
CNC Routing Services by Unofactory
High Volume CNC Machining Services by Unofactory
| Feature | Description |
|---|---|
Maximum Part Size | Milled parts up to 80” x 48” x 24” (2,032 x 1,219 x 610 mm). Lathe parts up to 62” (1,575 mm) length and 32” (813 mm) diameter. |
Standard Lead Time | 3 business days |
General Tolerances | Tolerances on metals will be held to +/- 0.005" (+/- 0.127 mm) in accordance with ISO 2768 unless otherwise specified. Plastics and composites will be +/- 0.010”. |
Precision Tolerances | Unofactory can manufacture and inspect to tight tolerances, including sub +/- 0.001" tolerances, per your drawing specifications and GD&T callouts. |
Minimum Feature Size | 0.020” (0.50 mm). This may vary depending on part geometry and chosen material. |
Threads and Tapped Holes | Unofactory can accommodate any standard thread size. We can also machine custom threads; these will require a manual quote review. |
Edge Condition | Sharp edges are broken and deburred by default |
Surface Finish | The standard finish is as-machined: 125 Ra or better. Additional finishing options can be specified when getting a quote. |
We are able to offer a precision machining service with a wide array of tolerances. The table below depicts the general tolerances for CNC machining:
Metal CNC Machining Materials
CNC Machining Aluminum Alloys
CNC Machining Copper Alloys
CNC Machining Bronze Alloys
CNC Machining Brass Alloys
CNC Machining Stainless Steel Alloys
CNC Machining Steel Alloys
CNC Machining Titanium Alloys
CNC Machining Zinc Alloys
Custom
Plastic CNC Machining Materials
ABS
Acrylic
Delrin (Acetal)
Garolite
HDPE
Nylon 6/6
PC (Polycarbonate)
PEEK
Polypropylene
PTFE (Teflon)
UHMW PE
PVC
ULTEM
Custom CNC
CNC Machining Finishes
Standard (As-Milled)
Bead Blast
Tumbled
Anodized (Type II Or Type III)
Titanium Anodize
PTFE Impregnated Hard Anodize
Chem Film (Chromate Conversion Coating)
Passivation
Powder Coat
Electropolishing
Electroless Nickel Plating
Silver Plating
Gold Plating
Zinc Plating
| Feature | Description |
|---|---|
Internal corner fillets | Design internal corner fillets to be 0.020” - 0.050” greater than a standard drill size for the radii. Follow a drill diameter to depth ratio of 1:6 (1:4 recommended) as a guideline for internal corner radii. |
Floor fillets | Design floor fillets smaller than corner fillets to allow the same tool to clear material from the interior. |
Undercuts | Always design undercuts to standard sizes and away from corners so they are accessible by the cutting tool. |
Tapped/threaded hole depth | Provide tool clearance slightly beyond the tapped hole depth to ensure complete threads. |
Complexity | Keep the number of small cuts to a minimum to reduce the CNC machining service cost; only design in the necessary features to balance function with aesthetic. |
CNC Machining FAQs
How does CNC machining work?
How does CNC machining differ from traditional machining?
What industries use CNC machining?
What is the history of CNC machining?
What are your inspection options for CNC machining?
What are your tolerances for CNC machined parts?
What are your CNC machining & turning capabilities?
Do you offer Quick-Turn CNC Machining?
Will I need to pay tariffs on internationally produced parts?
Advantages and Challenges of CNC Machining
CNC milling and turning are highly accurate and repeatable processes. Tight tolerances between +/-0.001″ – 0.005″ can be achieved, depending on specifications. Machines can be programmed to reliably run for 24 hours, 7 days a week if necessary, so CNC milling is a good way of getting parts produced on demand. Using standard tooling, a CNC machining service is particularly valuable for creating one-off parts, custom CNC parts, i.e., for replacing legacy components or delivering a specialized upgrade to a customer. It is also conceivable to scale single-part production to runs exceeding 10,000 units. Depending on the unit number, size, and complexity, the turnaround for CNC machined parts can be as short as one day. With shipping and delivery, deadlines can be met within a week.Another primary advantage of CNC technology is its achievable mechanical properties. By cutting away from bulk material, rather than thermally transforming it as in injection-molding or additive manufacturing, all desirable mechanical properties of the metal or plastic of choice are retained. More than 50 industrial-grade metals, alloys, and plastics can be machined using CNC milling and turning. This selection includes aluminum, brass, bronze, titanium, stainless steel, PEEK, ABS, and zinc. The only material requirement for CNC machining is that the part has an adequate hardness to be fixtured and cut. |
CNC Machining Applications
 |  |  |
Rapid ToolingBecause CNC machining can cut a high variety of fully dense, durable materials like aluminum 5052 and stainless steel, it is perfect for creating fixtures or molds. | Rapid PrototypingThe range of affordable metal alloys (like aluminum 6061) and plastics (like acetal or ABS) combined with the speed of our skilled machinists makes our online CNC machining service a great option for prototyping. | End-Use ProductionPerformance-enhancing finishes, precision tolerances as low as +/- 0.001”, and certifiable material options make CNC machining an excellent technology for end-use parts. |