CNC machining is a versatile and precise manufacturing process that can work with a wide range of materials. At InstaVoxel, we offer CNC machining services for both metals and plastics, each with its unique characteristics, advantages, and applications. This article provides an overview of the materials we work with, helping you choose the best option for your specific project needs. For detailed specifications and data sheets, please visit here.
Metal machining and plastic machining differ significantly due to the distinct properties of the materials and the techniques involved. Metals, being harder and denser, demand robust cutting tools and specialized processes like milling and turning, with higher cutting forces and heat resistance. Post-processing steps such as grinding may be necessary for achieving desired surface finishes. In contrast, plastics are softer and less dense, requiring different cutting tools and parameters to prevent melting or deformation. Machining processes for plastics involve milling, turning, and drilling, often at higher speeds and with less force. Additionally, plastics generally yield smoother surface finishes straight off the machine, reducing the need for extensive post-processing. This dichotomy underscores the necessity for tailored approaches in metal and plastic machining, each serving diverse industrial needs with precision and efficiency.
Metal Machining in CNC
| Material | Pros | Cons | Applications |
| Aluminum | Lightweight
High corrosion-resistant Excellent machinability Good thermal and electrical conductivity |
Relatively lower strength | Aerospace components
Automotive parts Consumer electronics |
| Brass | Good corrosion resistance
Excellent machinability Aesthetic appeal |
Softer than other metals
Can deform under high pressure |
Plumbing fittings
Musical instruments Decorative items Electrical connectors |
| Bronze | High wear resistance
High corrosion-resistant Excellent machinability |
Heavier and more expensive than brass | Bearings and bushings
Marine hardware Sculptures |
| Cast Iron | Excellent wear resistance
High strength and durability Good machinability |
Brittle, prone to cracking under stress | Engine blocks
Machinery bases Pipes Cookware |
| Copper | Excellent thermal and electrical conductivity
High corrosion-resistant Easy to machine |
Higher cost
Can tarnish over time |
Electrical components
Heat exchangers Plumbing Roofing |
| Tool Steel | High hardness
High wear resistance Good edge retention |
Difficult to machine
Prone to cracking |
Cutting tools
Dies and molds |
| Invar | Low thermal expansion
High dimensional stability |
Higher cost
Challenging to machine |
Precision instruments
Aerospace Scientific equipment |
| Stainless Steel | High corrosion-resistance
Strong and durable Good machinability |
Higher cost
Can be difficult to machine |
Medical devices
Food processing equipment Automotive parts Construction |
| Titanium | High strength-to-weight ratio
Excellent corrosion resistance Biocompatible |
Higher cost
Difficult to machine |
Aerospace components
Medical implants Military applications High-performance automotive parts |
Plastic Machining in CNC
| Material | Pros | Cons | Applications |
| ABS | High impact-resistant
Good machinability |
Poor UV resistance
Can degrade under prolonged exposure to sunlight |
Automotive parts
Consumer electronics housings Toys Prototyping |
| Acrylic
(PMMA) |
Transparent
Lightweight Good impact resistance |
Can crack under stress
Scratches easily |
Display case
Lenses Aquariums |
| Delrin (POM) | High stiffness
Low friction Excellent dimensional stability |
Poor UV resistance
Can be affected by strong acids |
Gears and bearings
Bushings Electrical insulators |
| Garolite G-10 | High strength
Good electrical insulation, moisture-resistant |
Difficult to machine
Can be brittle |
Circuit boards
Insulators Structural components |
| HDPE | High impact resistance
Good chemical resistance Lightweight |
Low strength compared to other plastics
Can deform under load |
Containers
Piping Cutting boards |
| Nylon | High strength
Good wear resistance Low friction |
Absorbs moisture, which can affect dimensional stability | Bearings and gears
Automotive parts |
| PEEK | High strength and stiffness
Excellent chemical resistance Can withstand high temperatures |
Higher cost
Challenging to machine |
Aerospace parts
Medical devices High-performance engineering components |
| Polypropylene
(PP) |
Good chemical resistance
Lightweight Flexibility |
Poor UV resistance
Can become brittle at low temperatures |
Packaging
Automotive parts Laboratory equipment |
| Polycarbonate
(PC) |
High impact resistance
Transparent Good dimensional stability |
Prone to scratching | Safety glasses
Medical devices Electronic housings |
| PVC | Excellent chemical resistance
Durable, easy to machine |
Can release harmful fumes when machined Brittle at low temperatures | Piping and fittings
Electrical insulation |
| PTFE
(Teflon) |
Non-stick properties
Low water absorption High corrosion resistance Low friction coefficient |
Not weldable
Low radiation resistance Higher cost |
Aerospace and automotive parts
Industrial applications |
| Ultem | High strength and stiffness
Excellent heat resistance Flame retardant |
Higher cost
Can be brittle |
Aerospace parts
Electronics components Medical devices |
In conclusion, understanding the properties of different materials and their suitability for specific CNC machining processes is crucial for optimizing your project outcomes. If you need components with high strength, durability, and resistance to heat, CNC machining of metals like aluminum, stainless steel, or titanium is ideal. For applications requiring lightweight, corrosion resistance, and electrical insulation, CNC machining of plastics such as ABS, Delrin, or PEEK will be beneficial. Now that you’re familiar with the CNC materials we offer, it’s essential to understand the corresponding post-processes for each material. Enhance your knowledge of surface finishing options by exploring our detailed article.
At InstaVoxel, our diverse CNC machining capabilities cater to a wide range of project requirements, ensuring that each endeavor is met with precision, efficiency, and quality. Contact us today to discover how our CNC machining expertise can elevate your next project to new heights.
