# Sandblasted Anodized Aluminum CNC Milled Heat Sink

Category: CNC Milling Parts
URL: https://www.machined-parts-factory.com/products/cnc-milling-parts/sandblasted-anodized-aluminum-cnc-milled-heat-sink/

This is a custom heat sink CNC milled from 6061 or 6063 aluminum, with fins, pin arrays, flat component pads and mounting holes cut to drawing. Parts are sandblasted and anodized, typically black, and component contact faces are held flat for good thermal transfer. It suits LED, power electronics and motor-drive designers needing non-standard thermal shapes.

- Fin arrays and pin fins cut from solid
- Flat component pads for thermal contact
- Black anodize with masked bare pads option
- Copper spreaders available for hot spots

## Specifications
| Spec | Value |
|---|---|
| Process | 3-axis CNC milling, slitting |
| Materials | Aluminum 6061-T6, 6063; copper inserts optional |
| Tolerance | ±0.05 mm standard; pad flatness per drawing |
| Surface Finish | Sandblasting, black or colored anodizing |
| MOQ | 1 piece |
| Drawing Formats | STEP, IGES, X_T, STL, DWG, DXF, PDF |
| Lead Time | Prototypes ~3–7 working days; production typically 10–20 working days |
| Inspection | First-article + 100% critical-dimension inspection; CMM report on request |
| Quality Control | 100% inspection of critical dimensions |

## How we make it
Fin arrays are machined with slitting saws or long-reach end mills, depending on fin depth and pitch. Thin fins are cut in alternating sequence to reduce vibration, and the base is left thick until the final pass. The component pad is finished last for flatness, sometimes fly-cut for a fine surface. Tapped holes for clips or screws are added in the same setup.

6063 aluminum has higher thermal conductivity than 6061 and is common for extruded heat sinks, while 6061 machines more cleanly for milled designs. Copper conducts heat roughly twice as well as aluminum but is heavier and costlier; it is used for inserts or spreaders. Black anodizing slightly improves radiation in natural convection; pads can be masked bare when thermal interface contact matters.

Pad flatness is checked on a surface plate, and fin thickness and pitch are measured at first article. Threads are gauged after anodizing and critical dimensions 100% inspected. Typical applications include LED lamp heads, motor drive boards, power supplies, audio amplifiers and battery management electronics, both in prototype and in production builds.

## FAQ
### Does black anodizing improve heat sink performance?
Slightly, mainly in natural convection where radiation plays a role. Black anodize has higher emissivity than bare aluminum. In forced airflow the effect is small. The anodize layer itself is thin, so it has minimal impact on conduction, but pads are often masked for best interface contact.

### When should a heat sink be machined instead of extruded?
Machine it for prototypes, small batches, or shapes that extrusion cannot produce, such as pin fins, varying fin heights or integrated mounting features. Extruded profiles are cheaper at volume for straight fins, and we can machine extrusions to add holes and pockets.

### How do I get a quote for sandblasted anodized aluminum cnc milled heat sink?
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