What is CNC Turning?

CNC turning is a substractive manufacturing process that create turned parts by rotating the rod material against a cutting tool, it is commonly used for functional prototypes and end-use parts with axial and radial holes, flats, grooves, and slots. If your parts design has symmetrical cylindrical or spherical features, CNC turning is recommended for you.

CNC Turning Capabilities

CNC turning machines can be categorized into two types: Lathe and CNC turning center. A CNC lathe only has 2 axis, which is the most affordable way to produce turned metal or plastic parts. A turning center that integrates milling, drilling, and sub-spindle capabilities and includes a Y-axis, which is commonly used for producing more complex designs.

Maximum part size

LimitationParameter (Metric)
Max swing diameter:360~800 mm
Max cutting length:270~1500 mm
Spindle bore:45~100 mm
Rapid moving speed:20 m/min
Spindle speed range:50-4200 r/mm
cnc turning process

Why CNC Turning with RapidDirect

dmf feedback and online quote

Instant Quoting

No more email back-and-forth, by simply uploading your design files and selecting the material and surface finish, our big-data-driven platform calculates an accurate and competitive CNC quotation in real-time.

strong capabilities

Strong Capacity

Having been in this industry for nearly 2 decades, RapidDirect has developed a team of engineers with profound CNC project experience. Get machining parts suggestions that achieve the same function at a lower cost.

Engineering support icon

Engineering Support

It is our tenet to always put the customers at the first place. We proudly have a dedicated customer success team that restlessly offers online chatting, email, and the phone supports to ensure the parts meet your expectations.

1M +
Parts Produced
10,000 +
Customers Served

Real Customer Feedback

I received the sample today and am very happy with the chrome finish as well as the overall look. I was also impressed with how well you packaged the items 🙂

— Alvaro Reese

Thank you for the attention to detail and working with us to get his first order completed. Your speed at communication and positive approach is a real credit. We look forward to an ongoing reliable relationship with you and your company.

Maren Ferrell

I received the part last night and I am really happy with the results. I plan to bring more orders to you in the future, mostly of one off custom parts. Thanks so much!

— Javion Garrett

Materials for CNC Turning

The various available materials is another advantage of CNC turning. At RapidDirect, you can choose from over 50 metal and plastic materials. We also provide material certification at your request.

Aluminum is a highly ductile metal, making it easy to machine. The material has a good strength-to-weight ratio and is available in many types for a range of applications.

Available Subtypes

  • Aluminum 6061

  • Aluminum 6061-T651

  • Aluminum 6063

  • Aluminum 7075

  • Aluminum 6082

  • Aluminum 2024

  • Aluminum 5052

  • Aluminum 5083

  • Aluminum ADC12 (A380)

cnc machining raw material - aluminum

Copper displays excellent thermal conductivity, electrical conductivity and plasticity. It is also highly ductile, corrosion resistant and can be easily welded.

Available Subtypes

  • Copper
  • Copper 101
  • Copper for EDM
  • Beryllium copper
  • Chromium zirconium copper
  • Tungsten copper
  • Antimony copper
cnc machining raw material - copper

Brass has desirable properties for a number of applications. It is low friction, has excellent electrical conductivity and has a golden (brass) appearance.

Available Subtypes

  • Brass 2680
  • Brass H59
  • Brass H62
  • Brass 260
  • Brass 385
  • Brass CAD260
  • Brass 360
  • Tin phosphor bronze
  • Aluminum bronze plate
  • Tin bronze
cnc machining raw material - brass

Steel is known for its high tensile strength and low costs. It is a ubiquitous material in the construction, infrastructure, automotive, maritime, tooling, manufacturing and defense industries.

Available Subtypes

  • 1045 Steel (45 #)

  • 1008 Steel

  • 1018 Steel

  • 1020 Steel

  • 1025 Steel

  • 11Smn30 Steel

  • 1215 Steel

  • 4041 Steel

  • 40Cr Steel

  • 4130 Steel

  • 4137 Steel

  • 4140 Steel

  • 42 Crmo Steel

  • 4340 Steel

  • 4J36 Steel Alloy

  • 5140 Steel

  • 5160 Steel

  • 60Si2Mn Steel

  • 65Mn Steel

  • A2 Tool Steel

  • A36 Steel

  • C3600

  • Class 8 Gray iron

  • Cr12Mov Steel

  • D2 mould steel

  • DC-01 Steel Cold rolled steel

  • EN16T Steel

  • EN3B Steel

  • EN8T Steel

  • H13 Steel

  • Inconel Steel

  • Invar 36 Steel

  • NAK80 Steel

  • P20 Steel

  • S136 Steel

  • S7 Steel Tool Steel

  • SK5 Steel

  • SKD11 Steel

  • SKD61 Steel

  • SKH51 Steel

  • ST37 (Q235) Steel

  • ZGmn13-5

  • Galvanized Steel / SGCC / SECC

  • S7 Steel

  • SCM440 (40CrMo) Steel alloy

  • 52100 Bearing Steel

cnc machining raw material- steel

Stainless steel typically contains a minimum of 10% chromium by weight. It is a popular metal within a broad range of industries, including construction, automotive, aerospace and more.

Available Subtypes

  • SUS304

  • SUS303

  • SUS301

  • SUS316

  • SUS316L

  • SUS401

  • SUS416L

  • SUS416

  • SUS420

  • SUS201

  • SUS430

  • SUS431

  • SUS440C

  • SUS410

  • SUS630 / 17-4PH

  • PP631 / 17-7PH

raw material - stainless steel bar / rod

Titanium is resistance to corrosion, chemicals and extreme temperatures, and has excellent strength-to-weight ratio. It has broad adoption in the aerospace, medical and defense industries.

Available Subtypes

  • TC4 Titannium Alloy
  • TC5 Titanium Alloy
  • Military-grade titanium Alloy
  • Food-grade titanium Alloy
  • R53400 Titanium Alloy 9
cnc machining product - titanium

Plastic is an indispensable part of our everyday world. It is known for its lightweight, high strength-to-weight ratio, electric insulation, low price, suitable for mass production, etc. The application of plastics is so wide that you can always see it in all industries.

Available Subtypes

  • ABS
  • PC
  • ABS+PC
  • PMMA
  • POM
  • PP
  • PA
  • PEEK
  • PET
  • PVC
  • PPSU
  • PPS
  • PTFE
  • PBT
  • PE
  • PEI
  • HDPE
  • UPE
  • CPVC
  • EPP
  • FR-4
  • HIPS
  • LDPE
  • PAI
  • PETG
  • PPA
  • PS
  • PVDF
  • Bakelite
Engineering Plastics

Surface Finishes for CNC Turning

CNC turned parts are left as-milled, and surface finsih can change the appearance, surface roughness, hardness and chemical resistance of the produced parts. Determined by the material using, a part can have one to serval available surface finishing options. Learn more at our surface finish page.

Anodizing changes the surface state and performance of the material, thus improving corrosion resistance, enhancing wear resistance and hardness, and protecting the metal surface.

Available materials:

surface finish - anodizing

Bead blasting directs abrasive material onto the surface, so as to alter and improved the properties of the workpiece surface - such as roughness and uniformity.

Available materials:
Aluminum, stainless steel, steel, copper, bronze, titanium, magnesium, zinc, all plastics

surface finish - bead blasting

Powder coating is a surface finishing technique used to create a hard finish tougher than normal paint. Commonly used for coat metal parts.

Available materials:
Aluminum, stainless steel, steel, copper, bronze, titanium, magnesium, zinc

surface finish - powder coating

Electroplating bonds fine layers of metal to the surface of another metal, thus reaching either functional, decorative, or corrosion-related properties.

Available materials:
Aluminum, stainless steel, steel, copper, bronze, titanium, magnesium, zinc

Electroplating Image

Polishing is the process of creating a smooth and shiny surface, it produces a surface with significant specular reflection, so as to improve the appearance of new or used metal parts.

Available materials:
Aluminum, stainless steel, steel, copper, bronze, titanium, magnesium, zinc, all plastics

Polishing Image

Brushing is a surface treatment process in which abrasive belts are used to draw traces on the surface of a material, usually for aesthetic purposes. Most commonly applied to aluminum.

Available materials:
Aluminum, stainless steel, steel, copper, bronze, titanium, magnesium, zinc, all plastics

Brushing Image

Painting involves spraying a layer of paint onto the surface of the part. It can improve the part's aesthetic appearance and can add a protective layer on the parts.

Available materials:
Aluminum, stainless steel, steel, copper, bronze, titanium, magnesium, zinc

Painting Image

Quality Reports & Certifications

full dimensional quality reports


During the production of every project, we strictly obey the ISO 9001:2015 requirements. We can provide material certifications, SGS, and ROHS certifications, please contact our sales team at your request.

Material certification

Quality inspection

We have a team of dedicated engineers who always feedback best practices for you. During production, the quality department conducts In-Process Quality Control every 30 minutes to minimize risks.

First part verification

Additional service

RapidDirect respects your intellectual properties, we always welcome NDA agreements for all order. For production orders, you can apply First-Article Inspection. In the end, you can always enjoy our Rework & Refund Policy.

CNC Turning Design Recommendations

Result from the processing features, CNC turning has slightly diffrent design guidelines with CNC milling process. Following these recommendations can greatly benefit the production efficiency and reduce cost. Learn more about CNC design guides.

Recommended: 0.8 mm (metals), 1.5 mm (plastics)

The less wall thickness, the less material stiffness. It will lead to the vibrations during machining and lower accuracy. We recommend you use even larger minimum wall thickness for plastics.

wall thickness cnc turning Image

Recommended Diameter: standard drill bit sizes

Recommended Depth: 4 - 40 times nominal diameter

The tools used for drilling holes are either drill bit or end mill tool. For high accuracy holes smaller than ⌀20 mm, using a standard diameter is recommended.

holes cnc turning Image

Recommended size: M6 or larger

Recommended length: 3 times nominal diameter

Threads are divided into internal and external ones. Internal threads are cut with taps, while external threads with dies. Taps and dies can be used to cut threads down to M2. CNC threading tools are common and they are preferred, as they limit the risk of tap breakage.

threads cnc turning Image

Upload CAD files and get a FREE quote today!

Instant Quote & Order

Only 4 simple steps to complete your project. Follow the instruction and give it a try!

Upload files
Get quotation
Place an order
Start production