About This Part
An automotive housing is a load-bearing enclosure that protects rotating assemblies, seals lubricants, and provides mounting points for sensors, connectors and brackets. In both EV and ICE platforms, these parts are expected to hold alignment over millions of cycles, seal against fluids, and do it all in a package that weighs as little as possible. Aluminum A380 housing components are among the most common production requests we see for automotive prototype housing through volume runs — and they are also one of the parts most often done poorly by shops that treat a casting as if it were a billet. This housing is machined from **Aluminum A380**, a die-cast alloy widely used in cnc machined motor housing and drivetrain components because of its excellent castability, pressure tightness and post-cast machinability. The die-cast blank arrives near-net shape, and our job is to finish-machine the datums, bores, seal grooves and mounting faces that the casting process cannot hold to tolerance. Critical bores, sealing faces and mounting datums are finish-machined on a 5-axis mill to **±0.005 mm on critical dimensions**. For ev component machining, where a bore misalignment can cause bearing noise, seal failure or accelerated gear wear, that level of control is non-negotiable.
**Part:** Automotive Housing
**Process:** 5-axis CNC milling
**Material:** Aluminum A380
**Tolerance:** ±0.005 mm on critical dimensions
**Inspection:** 100% CMM verification, full report with shipment
Challenges of This Part & How We Machined It
Machining through cast skin and subsurface porosity
A380 castings arrive with a hard, abrasive cast skin and unpredictable subsurface porosity. Diving straight into finishing passes with a generic feed rate can tear the surface or accelerate tool wear the moment the tool hits a hard spot — and porosity exposed during finish boring of a seal land is a scrap part, not a cosmetic issue. We start with a deliberate skinning pass at conservative parameters, inspect for porosity exposed after roughing (catching a bad casting early saves wasted finish-machining time), then run finishing tools on clean, predictable stock. This prevents unexpected tool deflection that would otherwise take bore roundness or face flatness out of spec.
Thin-wall chatter around bearing and seal bores
Housing geometry is defined by thin partitions between bores and external walls — the part is designed to be lightweight, which means very little rigidity where the cutting tool is working. Finish boring a main bearing seat on a wall that flexes 0.01 mm under cut load will produce chatter, out-of-round bores and poor seal surfaces. We use balanced boring heads with tuned overhang, light radial cuts, and custom fixturing that supports the part from the inside or opposite wall when needed. Bearing bores come out round, quiet and ready to accept seals without rework or hand-polishing.
Datum chain across multi-face features
A single housing carries datums on multiple faces: a mounting face on the bottom, bearing bores on the front face, ports or connector pads on sides or top. If each face is machined in a separate setup with manual re-indication, error accumulates fast — a few hundredths at each setup adds up to a port that does not line up or a bore that sits at an angle to the mount face. The 5-axis machine lets us access multiple faces in one clamping, keeping the datum chain intact from primary datums to every secondary feature. Face-to-bore perpendicularity and port position stay consistent across every part in the run.
Machining Sequence
1. **CAM programming with fixture simulation** — casting geometry is modeled from scanned or nominal blanks so toolpaths account for actual stock distribution, not just the finished model.
2. **Cast skin removal and rough milling** — all faces and bores are roughed to a uniform finish allowance, with porosity inspection after skinning to isolate bad castings early.
3. **5-axis finish milling and boring** — bearing bores, seal grooves, mounting faces and connector pads are finished in coordinated setups to maintain datum integrity across all features.
4. **Deburring and surface treatment prep** — all cross-holes and edges deburred, sealing faces protected from scratch damage before shipment, threads chased clean.
5. **CMM inspection** — bore diameters, roundness, face flatness, and port positions verified; CMM report and material certifications included with shipment.
What You Get With Every Order
- **Free DFM review before quoting** — we flag manufacturability risk early, not after parts are made - **First Article Inspection report** with the first batch - **CMM dimensional report** on critical features - **Material certificates** for aerospace and medical grades - **Direct communication with the shop** — no trading company in between, we make the parts ourselves
Have a Drawing?
Send us your drawing or STEP file and we will come back with pricing within 48 hours. Prototype quantities and production runs both welcome — no minimum order quantity.
**TruPart Precision** trupartprecision.com | sales@trupartprecision.com WhatsApp: +86 137 1278 3205 No.114 Xinhua Road, Xinhe Dev Zone, Wanjiang, Dongguan, China