Precision CNC Milling of Aluminum Monolithic Heatsink

In need of a custom monolithic heatsink for an RF module, a client in the test and measurement industry turned to H&S to take advantage of our experience in machining complex and challenging components.

During prototyping and early production runs, we realized that this complex structured monolithic heatsink required extensive and costly machining. Reworking the process, we engineered a design that started with an extrusion molded piece which reduced most of the machining. The extrusions were then CNC milled to the desired specifications.

The heatsink was composed of 6063-T5 aluminum and had final dimensions of 5.900″ x 3.526″ x 1.021″. A class 3 chromate conversion coating was applied per ASTM B449-93 standard; which acts as protection against corrosion and has low electrical contact impedance.

To maintain dimensional integrity, we used in-process testing and inspection equipment such as a Brown and Sharp Mistral CMM as well as visual inspections. These advanced quality capabilities verified that the required ±.001″ tolerances were met.

By re-engineering this component from a CNC milling only piece to combining CNC milling with extrusion molding, we reduced the run time and the project cost; the client realized an almost 40% reduction in the part price.

To learn more about this project, please contact us today or see the table below.


Product Description

RF Module

CNC Milling Capabilities Applied/Processes

CNC Milling

Conversion Coating
Part Marking

Equipment Used to Manufacture Part

Programmed using Virtual Gibbs
Kitamura HX400iSII Horizontal Machining Center

Overall Part Dimensions

5.900 x 3.526 x 1.021

Tightest Tolerances

+/- .001

Material Used

Aluminum 6063-T5

Material Finish

Chemical Conversion Coating ASTM B449-93, Class 3

  • Color: Clear
In process testing/inspection performed

Dimensional Inspection checked with Brown and Sharp Mistral CMM Coordinate Measuring Machine , Visual Inspection

Industry for Use

Test and Measure



Delivery/Turnaround Time

30 w/days

Delivery Location

Austin, TX

Standards Met

RoHS, Customer Specifications, 2D CAD Drawing, 3D Model Creo Parametric formerly known as Pro/E,ASTM B449-93, Class 3

Product Name

Monolithic Heatsink

Certifications We Adhere To