# Investment Cast and CNC Finished Stainless Steel Parts

Category: Precision CNC Machined Parts
URL: https://www.machined-parts-factory.com/products/precision-cnc-machined-parts/investment-cast-and-cnc-finished-stainless-steel-parts/

These are stainless steel parts produced by investment casting and then CNC machined on functional features. The lost-wax process forms complex near-net shapes, and machining finishes bores, threads, sealing faces and mounting holes to precise dimensions. It suits equipment and valve makers who order complex stainless parts in medium volumes, where machining from solid would waste material and time.

- Lost-wax casting for complex near-net shapes
- CNC machining on bores, threads and sealing faces
- 304, 316 and 17-4PH stainless steel
- Saves material versus machining from solid

## Specifications
| Spec | Value |
|---|---|
| Process | Investment casting (lost wax) plus CNC milling and turning |
| Materials | Stainless steel 304, 316, 17-4PH; carbon steel on request |
| Surface Finish | Bead blasting, polishing, passivation |
| Cast Tolerance | Typically ±0.1–0.3 mm on unmachined surfaces |
| Tolerance | ±0.05 mm standard; down to ±0.005 mm on critical features |
| MOQ | 1 piece; prototypes through mid-volume runs |
| Drawing Formats | STEP, IGES, X_T, STL, DWG, DXF, PDF |
| Lead Time | Prototypes typically 3–7 working days; production usually 10–20 |
| Inspection | FAI, in-process checks, 100% critical dimensions; CMM |

## How we make it
A wax pattern is injected in an aluminum die, assembled on a tree, coated with ceramic shell and melted out. Molten stainless steel fills the shell, which is broken away after cooling. The cast part is cut off, ground and heat treated if required. CNC fixtures then locate on cast datum features, and functional surfaces are milled, turned, drilled and tapped.

304 and 316 stainless cast well and suit valve bodies, marine fittings and food equipment parts; 17-4PH can be hardened for strength. Investment castings typically hold around ±0.1–0.3 mm on unmachined surfaces with a roughness near Ra 3.2–6.3 µm. Machined features reach normal CNC tolerances. Passivation, polishing and bead blasting are common finishes.

First castings are checked for dimensions, porosity and surface defects, and machined features are inspected with CMM and thread gauges. Critical dimensions are verified on every part before shipping. Typical parts are valve bodies, pump impellers, marine hardware, lever arms, brackets, food machinery components and hinges where shape complexity and corrosion resistance are both needed.

## FAQ
### When is investment casting better than machining from solid?
When the part has complex shapes, curved internal passages or thin sections, and order volume is high enough to pay for the wax die. Casting reduces material waste and machine time, especially in stainless steel. For a few pieces or simple shapes, machining from solid is usually cheaper and faster.

### What tolerance can a stainless investment casting hold?
As-cast surfaces typically hold about ±0.1–0.3 mm depending on size, with larger dimensions requiring more allowance. Features that need tighter tolerances, such as bores and sealing faces, are left with machining stock and CNC finished to ±0.05 mm or better.

### How do I get a quote for investment cast and cnc finished stainless steel parts?
Send a 3D model (STEP or IGES) and a 2D drawing with tolerances, material, finish and quantity through the quote form or by email. An engineer replies within 24 hours on business days with price, lead time and any DFM suggestions.

Request a quote: https://www.machined-parts-factory.com/contact/#rfq — inquiry@machined-parts-factory.com — WhatsApp +86 176 2154 1688