CNC Machining a Thin-Wall 6061-T6 Aluminum Bottom Housing for an Aerospace Application
Richconn helped produce a thin-wall aluminum bottom housing with strict 0.05 mm flatness and parallelism requirements. By combining material stress relief, controlled roughing allowance, custom vacuum fixturing, high-speed machining, and full inspection, the project achieved stable dimensions and a 99% in-process yield.
Thin-Wall Aluminum Housing with Tight Geometric Tolerances
The part was a bottom housing used in an aerospace-related application. Although the production quantity was only 20 pieces, the machining difficulty was high because the part had a thin-wall structure with approximately 1 mm wall thickness and required both flatness and parallelism within 0.05 mm.
For thin-wall aluminum parts, the main manufacturing risk is not only achieving the required dimensions, but also keeping the part stable after internal material stress, clamping force, tool pressure, and surface treatment are introduced.
Why This Part Was Difficult to Machine
The customer needed a thin-wall aluminum housing with tight form and orientation tolerances. The required flatness was 0.05 mm, and the required parallelism was also 0.05 mm. Because the wall thickness was only around 1 mm, the part was highly sensitive to deformation during machining and after clamping release.
Main Manufacturing Risks
- Thin-wall structure made the part easy to deform under cutting force and clamping pressure.
- 6061-T6 aluminum could release internal stress during material removal.
- Flatness and parallelism of 0.05 mm were difficult to maintain after roughing and finishing.
- Rework or scrap would increase the unit cost because the order quantity was only 20 pieces.
- Surface treatment could introduce additional dimensional variation, requiring final inspection before shipment.
The Core Problem Was Thin-Wall Deformation
The major issue was not a single machining parameter, but the combined effect of material stress, wall thickness, clamping method, and tolerance requirements. For a 6061-T6 aluminum thin-wall housing, aggressive material removal or uneven holding force can easily cause distortion. Once the part deforms, holding 0.05 mm flatness and 0.05 mm parallelism becomes difficult.
| Material Behavior | 6061-T6 aluminum can deform when internal stress is released during material removal, especially in thin-wall structures. |
|---|---|
| Structural Risk | The approximately 1 mm wall thickness reduced part rigidity and made the housing sensitive to cutting force. |
| Tolerance Requirement | The part required 0.05 mm flatness and 0.05 mm parallelism, which demanded stable fixturing and controlled finishing. |
| Cost Pressure | Because the order quantity was 20 pieces, maintaining first-pass stability was important for controlling machining cost. |
How We Controlled Deformation and Improved Dimensional Stability
Richconn used a process route focused on stress reduction, stable holding, controlled stock allowance, and inspection at critical stages. Instead of relying only on final machining, we controlled the risk from material preparation to final outgoing inspection.
Stress Relief Before Machining
The 6061-T6 aluminum raw material was annealed to release internal material stress before precision machining.
Controlled Roughing Allowance
Rough machining was performed first with a 0.5 mm allowance left for finishing, reducing the risk of sudden deformation.
Custom Vacuum Fixture
A dedicated vacuum suction fixture was made to support the thin-wall part more evenly during finishing.
Full Inspection
Full inspection was carried out during machining, and the parts were inspected again after surface treatment before shipment.
In-process machining yield after process optimization
Stable Dimensions and Lower Machining Cost
After optimizing the process, the in-process qualification rate increased to 99%. The improved process helped reduce machining cost, stabilize the part dimensions, and meet the customer's requirements for flatness, parallelism, and overall product quality.
- Flatness requirement: 0.05 mm
- Parallelism requirement: 0.05 mm
- Material: 6061-T6 aluminum
- Process: CNC machining center with high-speed machining capability
- Inspection: full inspection during machining and after surface treatment
What Buyers Should Know About Thin-Wall Aluminum CNC Machining
Thin-wall aluminum parts are often more difficult than they look. When flatness, parallelism, and surface quality are all important, the machining strategy must consider material stress, fixture design, machining sequence, tool path, and inspection frequency together.
For aerospace-related housings and precision structural components, a stable manufacturing process is usually more important than simply selecting a CNC machine with high spindle speed.
Richconn’s Practical Experience
- Understand the material behavior before defining the machining process.
- Reduce thin-wall deformation through stress relief and staged machining.
- Use custom fixturing when conventional clamping may distort the part.
- Leave proper finishing allowance instead of cutting to final size too early.
- Inspect after both machining and surface treatment when tight tolerances are required.
Related CNC Machining Services
Richconn provides custom CNC machining services for precision aluminum parts, thin-wall components, housings, fixtures, and complex custom metal parts.
FAQ About Thin-Wall Aluminum CNC Machining
Why are thin-wall aluminum parts easy to deform during CNC machining?
Thin-wall aluminum parts have lower structural rigidity. Cutting force, clamping pressure, internal material stress, and heat can all cause distortion during machining or after the part is released from the fixture.
How can flatness and parallelism be controlled on thin-wall parts?
Common methods include stress relief before machining, staged roughing and finishing, proper finishing allowance, custom fixtures, optimized tool paths, controlled cutting parameters, and inspection during key process stages.
Why was a vacuum fixture used for this aluminum bottom housing?
A vacuum fixture can provide more even support compared with localized mechanical clamping. For thin-wall parts, this helps reduce clamping deformation during precision finishing.
Can Richconn machine similar aerospace aluminum housings?
Yes. Richconn can support custom CNC machining of aluminum housings, thin-wall parts, structural components, and precision parts based on customer drawings, tolerance requirements, materials, quantities, and surface treatment needs.
Need a Thin-Wall Aluminum Part Machined to Tight Tolerances?
Send us your drawings, material requirements, tolerance notes, surface treatment needs, and annual quantity. Our engineering team will review the manufacturability and provide a practical machining solution.