CNC machining, short for computer numerical control machining, is a subtractive manufacturing
technique that utilizes computerized controls and machinery to selectively remove material layers
from a solid block. Precise cuts in the material are orchestrated through programmed instructions,
allowing automated machinery to execute the machining tasks with accuracy and efficiency.
Product Details
The CNC machining process predominantly employs metals as its primary materials.
These metals encompass alloy steel, carbon steel, cast iron, stainless steel, aluminum, copper,
magnesium, and zinc.
Nonetheless, this versatile process can also be applied to machine plastic components and work
with an array of other materials, including ceramics, composites, thermoplastics, and thermosets.
Common Materials | |
Name | Description |
Aluminum | High machinability and ductility, good strength-to-weight ratio. |
Stainless steel | High tensile strength, corrosion and temperature resistant. |
Mild steel | High machinability and weldability, high stiffness. |
Brass | Low friction, excellent electrical conductivity, golden appearance. |
Copper | Excellent thermal and electrical conductivity. |
Titanium | Excellent strength to weight ratio, used in aerospace, automotive and medical industries. |
ABS | Common thermoplastic, impact resistant, easy to machine. |
Nylon | Excellent mechanical properties, thermal, chemical and abrasion resistant. |
POM | High stiffness, high accuracy, low friction, easy to machine. |
Post-processing and surface finishes for CNC machining
CNC-machined parts as they emerge from the machine often exhibit visible tool marks,
a feature that may not align with your specific part requirements.
Fortunately, there exists a multitude of post-processing techniques aimed at enhancing the
surface appearance and elevating attributes such as wear resistance, corrosion resistance,
and chemical resistance.
Methods like anodizing, bead blasting, and powder coating present viable options for refining
the final presentation of your custom parts, allowing you to achieve the desired surface
quality and performance characteristics.
Surface Finishes | ||
Name | Applicable to | Machining marks |
As machined | Metals, Plastics | Visible, light surface scratches |
Smooth machining | ||
Fine machining | Metals | Slightly visible |
Polishing | Metals | Removed on primary surfaces |
Bead blasting | Metals | Removed for non-cosmetic, removed on primary surfaces for cosmetic |
Brushing | Metals | |
Anodizing Type II | Aluminum | |
Anodizing Type III | Aluminum | Visible under anodizing |
Black oxide | Copper, Stainless steel, Alloy steel, Tool steel, Mild steel | Visible |
Powder coating | Metals | Removed |
Brushed + electropolishing | Stainless steel | Removed on Primary surfaces |
Specialist Industries
We’ve manufactured millions of parts for all sorts of applications, but we’re especially
knowledgeable in these areas.
1. Aerospace & aviation
2. Automotive
3. Industrial machinery
4. Consumer electronics
5. Robotics & automation
6. Medical
Company Profile
Factors Influencing Machining Costs
The cost of CNC machining projects is influenced by various factors that play a significant role
in cost estimation. Manufacturers seeking to manage expenses effectively and optimize their
processes should be aware of these key elements that determine machining costs:
1. Material Selection:
The choice of raw material directly impacts machining costs.
Different materials have varying costs, availability, and machining characteristics.
High-performance alloys may be more expensive than common metals.
Material availability affects pricing, and considering material type is essential for cost calculation.
2. Complexity of Design:
The complexity of the machined part affects cost determination.
Intricate features, tight tolerances, and complex geometries require advanced machining
techniques, specialized tooling, and longer machining time.
Producing complex components requires additional precision and expertise, increasing overall costs.
3. Machining Time:
Machining time is a critical cost factor.
Longer machining times result in higher costs.
Machining time includes cycle time, setup time, and overall production efficiency.
Optimizing processes to reduce cycle time and enhance setup efficiency minimizes costs and
improves productivity.
4. Machine Tooling:
The choice and management of machine tooling impact machining costs.
Tooling costs, including purchase, maintenance, and replacement of cutting tools, should be
considered.
Cutting tool lifespan and changeover time affect production efficiency and costs.
Proper tooling selection, maintenance, and optimization control expenses.
5. Volume and Batch Size:
Production volume and batch size directly affect machining costs.
Economies of scale apply to larger production volumes, reducing the cost per part.
Balancing volume with setup time is crucial; small batches may have higher costs due to
increased setup time, while larger volumes benefit from lower per-part costs.
6. Labor Costs:
Labor costs, including wages for CNC machining engineers and operators, contribute significantly
to expenses.
Skilled operators with expertise in CNC programming, setup, and operation are essential.
Labor-intensive operations or complex part requirements may involve additional labor costs.
7. Overhead Costs:
Overhead costs related to CNC machining operations impact overall cost calculations.
These costs encompass facility expenses, utilities, administrative costs, quality control, and
inspection.
Managing and optimizing overhead expenses are vital for cost control and competitiveness.
8. Scrap and Rework:
Scrap and rework costs are crucial considerations.
Material waste due to errors or deviations from specifications increases costs.
Effective quality control measures, precision machining techniques, and robust inspection
processes minimize scrap and rework, reducing overall machining expenses.
Understanding and analyzing these factors enables manufacturers to identify areas for improvement,
implement cost-saving measures, and optimize CNC machining processes for enhanced efficiency
and profitability.