Common Mistakes to Avoid When Ordering CNC Aluminum Parts

One of the most frequent issues is failing to define tolerances clearly.

• CNC machining can achieve extremely tight tolerances, sometimes as precise as ±0.01 mm.
• Without clear specifications, parts may not fit assemblies properly, leading to rework or failure.

Tip: Always highlight critical dimensions and tolerances in your technical drawings.

Aluminum comes in various grades, each with unique mechanical properties:

• 6061: General-purpose, good corrosion resistance
• 7075: High-strength applications
• 5052: Excellent corrosion resistance for marine environments

Selecting the wrong alloy can compromise strength, machinability, or durability.

Tip: Discuss your functional requirements with your supplier to choose the most suitable alloy.

Surface finish affects both functionality and aesthetics. Common finishes include:

• Anodizing for durability and corrosion resistance
• Black oxidation for protective coating
• Polishing for smooth, visually appealing surfaces

Failing to specify finishes can result in rough surfaces or additional post-production work.

Vague or incomplete drawings are a major source of errors.

• Clearly mark all dimensions, hole locations, threads, and features
• Providing 3D CAD models alongside 2D drawings reduces misunderstandings

Tip: A complete, detailed drawing is your best insurance for precise manufacturing.

Small batch orders are possible, but misjudging:

• Minimum Order Quantities (MOQ)
• Expected lead times

…can disrupt your project timeline.

Tip: Confirm MOQs and production schedules with your supplier before placing the order.

Cost is important, but lowest price doesn’t always mean best results:

• Low-cost suppliers may compromise on precision, surface finish, or QC
• Experienced CNC manufacturers ensure reliable, high-quality parts

Tip: Prioritize proven experience and quality assurance over price alone.