CNC Machining Materials Guide for Precision Parts
Material choice drives function, cost and lead time. Mingchen machines brass, stainless steel, aluminum, copper, iron/carbon steel, tungsten steel and engineering plastics every day — here is a practical overview to help you specify the right one for your turned or milled components.
Materials We Machine In-House
Brass
Excellent machinability, corrosion resistance and a clean finish. A first choice for connectors, threaded parts, valves and decorative hardware.
Stainless Steel
Strength and corrosion resistance for fasteners, shafts, rings and parts exposed to moisture or washing. Slower machining than brass — plan cost accordingly.
Aluminum
Lightweight, good strength-to-weight ratio and fast machining. Common for brackets, housings, plates and electronic hardware.
Copper
High electrical and thermal conductivity for terminals, contacts, busbar parts and heat-path components.
Iron / Carbon Steel
Strong, rigid and economical for structural hardware, shafts and heavy-duty components.
Tungsten Steel
Hard, wear-resistant material for tooling components and parts that must survive abrasion.
Engineering Plastics
Nylon and POM (acetal) for lightweight, insulating, low-friction and wear-resistant parts such as bushings, spacers and insulators.
Need a comparison?
If two materials both seem viable, engineering will help you weigh function, machinability and cost before quoting.
Choosing a Material — Practical Notes
These rules of thumb come up in almost every quoting conversation:
- Tolerance vs. material: softer metals (brass, aluminum) and stable plastics machine predictably; every material has limits at ±0.005 mm scale, so confirm with engineering.
- Environment: consider moisture, chemicals, temperature and galvanic pairing with mating parts before finalizing stainless vs. brass vs. aluminum.
- Volume economics: material cost and machining speed both move the unit price — free-machining brass often wins on total cost for high-volume small parts.
- Supplier-supplied material: if your company supplies the raw material (material-supplied processing), we machine to your specification and return finished parts.
Typical Uses by Material
| Material | Typical components | Selection notes |
|---|---|---|
| Brass | Threaded rings, connectors, nuts, valve parts, fittings | Best all-round machinability; bright finish; great for threaded details |
| Stainless steel | Shafts, pins, fasteners, rings, washdown parts | Corrosion resistance and strength; budget more machining time |
| Aluminum | Brackets, housings, plates, electronic hardware | Light, fast to machine, anodizing-friendly |
| Copper | Terminals, contacts, heat-path parts | Conductivity first; machining is straightforward |
| Iron / carbon steel | Structural hardware, shafts, heavy parts | Strength and economy; protect against corrosion if needed |
| Tungsten steel | Wear components, tooling elements | Very hard; confirm form and tolerances with engineering |
| Nylon / POM | Bushings, spacers, insulators, wear parts | Self-lubricating options; low weight; stable POM for tighter tolerances |
See machining process pages for what is achievable: CNC turning, CNC milling and Swiss-type machining.
Common Questions
Can you machine the material I specify if it is not listed?
Do you sell raw material too, or only machine customer material?
Which material is cheapest for a high-volume small part?
Not Sure Which Material Fits?
Describe the application and environment — we will recommend a material and quote machining from the same conversation.