Rapid Custom ManufacturingRapid Custom Manufacturing

Aluminum Machined and Anodized Prototype

Project Overview:

Manufacturing Process: CNC Machining and Boring
Part Material: Aluminum 6061-T6
Part Dimensions: 390.00 × 213.00 × 130.00 mm
Surface Finishing: Sanding, Tapping 1-1/2" BSPT & M12, Anodizing
Manufacturing Tolerance: ± 0.1 mm
Quantity and Lead Time: 1 Unit, 7 Days

Customer was a western Australia company offering professional service and engineered solutions for fluid systems around the world. This aluminum prototype was made to test its liquid pressure and fitting before low volume manufacturing. Considering big dimensions and multi-sided milling, shape stability and milling tolerance were challenges of this project.
CNC Aluminum Machining   CNC Prototyping Step By Step:

Step 1: CNC machining the first side. As an subtractive manufacturing process, the base material in block to be milled was usually 3 cm longer & wider and 0.5 cm thicker than the part dimensions. It usually started from coarse milling by big and strong cutting tools to fast remove the unwanted material, to gradually smaller tools to mill the fine and detailed features.


Step 2: CNC machining the second side. For 3 axis CNC the multi-sided milled part, the workpiece was rotated manually to be milled side by side, the workpiece must be accurately relocate to ensure the milling tolerance. 5 sides (usually 6 sides of a part) of this aluminum prototype were rotated to be milled. An ABS fixture (the bottom yellow one) was used to prevent the workpiece deformation during prototype machining.   CNC Aluminum Milling
CNC Milling AluminumStep 3: CNC machining the third side. The main shape of this aluminum prototype came out after completion of the first and second side's milling. The fourth side was to mill the 6 holes at the bottom of the part.
CNC Machining Aluminum Step 4: CNC machining the fifth side. One of two deep holes on this side was bored instead of milled as it was out of the milling capability. Tapping 1-1/2" BSPT was for achieving sealability and was done by also boring.
Aluminum Machined PrototypeStep 5: The CNC milled prototype prior to surface finishing. All cutting lines and burrs on the milled surface were removed by sanding, then proceeded with the further finishing of beadblasting and anodizing dark blue.
Aluminum AnodizingStep 6: The final finishing of aluminum anodizing. The thin anodized film provided aesthetic feeling and corrosion & abrasion resistance for the part, different colors and glosses could be achieved by aluminum anodizing.


Aluminum Milled and Anodized Prototype   Step 7: The finished aluminum prototype for delivery. After finishing liquid pressure and fitting test of the arrived prototype, customer was happy to proceed with the low volume manufacturing of 10 units shortly.


How to Make a Quality Aluminum Milled and Anodized Prototype:

• Quality Material Used. The anodizing quality was considerably affected by the aluminum material composition.
• Quality Anodizing Technique. The intended color & gloss can be matched as close as possible by excellent anodizing technique.
• Quality CNC Milling. CNC milling delivered the tight tolerance also helped get quality surface finishing.