Precision Machined Parts, Delivered Fast

On-Demand CNC Machining Services

Get tight-tolerance CNC parts without the runaround — no minimums, expert manufacturing advice, rigorous quality standards.
AS9100, ISO 9001:2015, and ITAR registered.
 

Is CNC Machining Right for Your Part?

How CNC Machining Works

CNC machining uses computer-controlled tools (mills, lathes, multi-axis platforms) to remove material from metal or plastic stock. Because parts are cut from solid, you get inherent material properties, repeatable tight tolerances, and excellent surface finishes—ideal when performance and precision matter. At A3D, recommendations are application-first and process-agnostic—we’ll point you to CNC, additive, or hybrid depending on the best fit.  

What Is CNC Machining Ideal For?

  • Functional prototypes that must behave like end-use metals or
    engineering-grade plastics
  • Tight-tolerance components (like bearing fits, sealing interfaces,
    and precision enclosures)
  • Low- to mid-volume production when hard tooling isn’t justified
  • Complex geometries requiring multi-axis strategies, threads,
    pockets, and datum-driven GD&T
  • Regulated programs that need traceability, FAIR/AS9102, and
    final QA (no blind drop-ship)

Common CNC Applications

Precision Housings & Manifolds

Test Fixtures, Shafts, & Impellers

Surgical Jigs

Aerospace Brackets

Drivetrain Components

Robotics Gearboxes

Regulated Sub-Assemblies

At a Glance: Advantages vs. Other Processes

If another process is a better fit for cost, weight, or timeline, we’ll
recommend it. You can rely on one partner from prototype to
production with hybrid, additive, and traditional capabilities.

  • Tightest practical tolerances and true datums (great for tight-tolerance machining)
  • Exotic materials (heat-trained steels and stainless steels,
    6061-T651, titanium, and PEEK)
  • Finish control (machined, bead-blast, anodize, chem film, and
    passivation)
  • Flexibility without tooling (iterate fast and change features
    between builds)
  • Documentation and trust (FAIR/AS9102, CMM reports, and
    final inspection for predictable outcomes)

Our Capabilities & Technical Specifications

Milling & Multi-Axis

  • 3-axis, 4-axis, and 5-axis (indexed and simultaneous)
  • High-speed and hard-metal machining
  • Custom fixtures or soft jaws

Turning & Mill-Turn

  • 2-axis and multi-axis lathes with live tooling
  • Y-axis, sub-spindle, bar feed, and chucking
  • Swiss-type for ultra-small precision parts

EDM, Grinding, & Specialty

  • Wire/sinker/hole-pop EDM
  • Surface and cylindrical grinding, and lapping
  • Broaching
  • Deep-hole drilling
  • Reaming and tapping

Cutting & Secondary Processes

  • Laser or water jet (as needed)
  • Deburr, bead blast, tumble, part marking, assembly, and knitting

Typical Tolerances & GD&T

  • Standard: to ±0.005 in (0.127 mm)
  • Tight-tolerance machining: ±0.0005 in (12.7 μm) on request (material or geometry dependent)
  • GD&T per drawing and UNC/UNF/ISO metric threads
  • Inspection: CMM/vision; FAIR/AS9102, PPAP, CPK, Capabilities Study on request

Materials We Offer

Metals

6061/7075/2024/7050 Al

303/304/316/17-4PH SS

1018/4140/4340 steels

Tool steels (A2/D2/O1/S7/H13)

Ti-6Al-4V, Inconel 625/718

Copper, brass, bronze

Magnesium and zinc (on request)

Plastics

Acetal/Delrin (POM)

Nylon (PA)

PEEK

PEI (Ultem)

PTFE

ABS

PC

PMMA

PVC

HDPE

UHMW

G10/FR-4

PPS

PPSU

Finishes & Treatments

Andodize Type II/III (hardcoat)

Chem Film/Chromate

Passivation

Zinc/Tin/Silver/Gold (select apps)

Black Oxide

Powder Coat & Paint

Bead Blast

Laser marking & serialization

Cleanroom packing (as needed)

Heat Treat (solution/aging, quench/temper, case hardening, nitriding)

Quality & Compliance

AS9100 • ISO 9001:2015 • ITAR Registered

We apply rigorous certification standards to every project, ensuring you receive the highest quality products on time, everytime. You can expect your parts to route through A3D headquarters in Phoenix, Arizona, for final QA – no blind dropshipping – so you get predictable outcomes with documentation when needed.

Why this matters to you

  • Engineers: tighter control, fewer surprises, faster validation
  • Startups: scalable production without new vendor risk
  • Supply Chain: traceability, documentation, and consistent delivery from a single accountable partner

Common CNC Machining FAQs

What are the design guidelines?

We break down our design guidelines into four main categories below:

  1. Number of Operations: The location and accessibility of a part’s features will dictate how many setups or
    operations are required. Parts with multiple setups may suffer a small tolerance loss between features.
    Multiple operations can also affect a project’s cost and lead time.
  2. Reach vs. Width: Long, thin cutters deflect and break. When reaching into a deep pocket, keep the radius
    large to accommodate a thicker, more robust cutter.
  3. Internal Stresses: Residual internal stresses in the workpiece, coupled with elevated temperatures
    involved in the cutting operation, can cause parts to deflect. This effect is exacerbated when a large
    amount of material is being removed from a thin, flat workpiece.
  4. Radii & Tool Access: Rotating cutting tools are essentially cylinders, meaning that internal vertical corners
    need a radius, if only a small one. If the cutting tool is unable to reach a feature, it cannot be CNC
    machined. Careful tool selection can reach some mild undercuts, but as a general rule, all features should
    be in line-of-sight. This effect is exacerbated when a large amount of material is being removed from a
    thin, flat workpiece
What is the standard finish for CNC machined parts?

Due to this process, some visible tool marks may be seen.

If additional finishing is required, please note in your drawings and in your request for quote.

What are finish options are available for CNC machining?

Our finish options are anodized, bead blast, chem film, passivation, and powder coat.

What tolerances can you hold?

We hold standard to ±0.005” and tight-tolerance machining down to ±0.0005” depending on material or
geometry

What’s your typical lead time?

Our standard lead time is 14-20 days. We also offer expedited options by request.

Do you have certifications?

Yes, we have AS9100, ISO 9001:2015, and ITAR registered certifications.

How do you ensure quality from partners?

Every supplier is vetted and tiered. No blind drop-ship orders and parts are routed through our A3D
Manufacturing headquarters in Phoenix, AZ for final QA.

Do you have minimum order quantities?

No minimums. We build 1-1,000+ parts with the same attention to detail, so you can scale how you want and
when you want.

How does your online quoting work?

Just simply upload STEP/IGES/Parasolid/SOLIDWORKS type files to request an instant quote.

Every CNC project is reviewed by our manufacturing experts to offer the highest level of review and accuracy
to discuss DFM strategies, process selection, and risk flags