Custom Aluminum Die Cast Mounting Base for Electronic Equipment

This custom aluminum die cast mounting base was developed for an electronic equipment project in the US. The part is relatively compact—approximately 80 × 35 mm—but a large number of mounting and locating features are concentrated within its narrow footprint.

That made the manufacturing approach different from a simple cover or enclosure.

The customer supplied both 2D drawings and 3D CAD data. Before tooling, we reviewed the part for die casting, identified the areas that would require CNC finishing, and confirmed the DFM and final design with the customer.

A 2-cavity die casting tool was then manufactured. Tooling takes approximately 4 weeks after the final DFM and drawing are approved.

After casting, the parts go through secondary CNC machining, polishing, sandblasting and powder coating in the customer's specified color.

Project Details

The Challenge Is in the Mounting Layout

At first glance, this is a small aluminum base. Looking more closely, however, there are mounting pads, bosses, holes, pockets and locating features distributed along almost the entire length of the part.

These features do not work independently.

Once electronic or mechanical components are installed on the base, the location of one mounting point may need to correspond with another hole, pad or locating surface elsewhere on the same casting.

That is where the manufacturing plan starts.

Instead of applying tight machining requirements everywhere, we separate the geometry into two groups: features that can remain as-cast and interfaces that need CNC finishing.

This keeps the process practical while reserving additional dimensional control for the areas that actually affect assembly.

Before Cutting the Tool, We Review What Happens After Casting

The DFM for this part was not limited to draft angles or whether the cavity could fill.

We also had to consider what would happen later.

Which surfaces would be used to locate the casting during CNC machining? Where should machining stock be left? Which mounting areas needed secondary finishing? Would any threaded or functional areas need protection during powder coating?

At the same time, the usual die casting considerations still apply—wall transitions, bosses, radii, draft, parting line, ejection and the general tooling layout all need to make sense.

Where the original design and the manufacturing process need to meet somewhere in the middle, we discuss the details with the customer before tooling.

Only after the DFM and final part drawing are confirmed do we release the 2-cavity die for manufacturing.

Using the Casting as the Starting Point for CNC

High-pressure die casting creates most of the component close to its finished geometry.

That includes the overall base, many of the bosses, pockets and other integrated features visible on the part. CNC machining is then reserved for the drawing-controlled areas.

Depending on the final drawing, secondary operations may include machining mounting pads, finishing locating surfaces, drilling or reaming holes, tapping threads, or finishing selected recessed areas.

The important part is the setup.

Where several features need to maintain a defined relationship, they can be machined from common datum references rather than being treated as unrelated holes or surfaces.

Machining allowance for these areas is already considered before the die is built. We are not waiting for the casting to arrive at the CNC machine and then deciding how to make it work.

A Narrow Base Has to Stay Consistent Through Several Processes

The elongated shape of this mounting base also deserves attention.

After leaving the die, the component still has to go through trimming, CNC machining, polishing, sandblasting and powder coating. Each operation introduces handling and fixturing, so functional areas need to remain protected as the part moves through production.

For CNC machining, the casting needs a repeatable location in the fixture. After machining, finished interfaces should not be damaged during polishing or blasting.

Then comes powder coating.

A coating that looks good but builds up on the wrong mounting surface can still create an assembly problem. Threaded holes, machined interfaces or other coating-sensitive areas can therefore be masked according to the customer's drawing.

This is one reason we prefer to consider machining and finishing requirements while reviewing the part for tooling, rather than treating them as decisions for later.

Powder Coating to the Customer's Color Requirement

The required finish for this project includes polishing, sandblasting and powder coating.

Polishing is used locally where necessary to clean up or blend the required areas. Sandblasting provides a more uniform surface condition before the powder finish is applied.

The customer specifies the required coating color, and masking requirements are defined according to the functional features of the component.

By the time the part reaches powder coating, the important machined areas have already been established. The finishing process therefore needs to improve the exterior without changing the interfaces needed for assembly.

We Inspect the Base Before the Finish Can Hide a Problem

There is little value in discovering a machining issue after a part has already been powder coated.

For that reason, the mounting and locating features are checked after CNC machining and before the final finish. Drawing-defined relationships between functional features are verified according to the applicable requirements.

Once powder coating is complete, inspection shifts to the finished surface—coverage, appearance, specified color, masking edges and protected areas.

The sequence sounds simple, but it matters on a part with this many features in a small space:

make the casting first, establish the functional interfaces, verify them, and only then complete the cosmetic finish.

Custom Aluminum Die Casting for Electronic Equipment Parts

This project is a good example of a custom die cast aluminum part where the raw casting is only the beginning of the job.

The customer needs a finished mounting base made to their own design—not a standard catalog component. That means the tooling, casting, CNC machining and powder coating all have to follow the same drawing requirements.

For similar electronic and industrial equipment projects, we can work from customer 2D drawings and 3D CAD files and provide DFM, custom aluminum die casting tooling, high-pressure die casting, secondary CNC machining and surface finishing.

If you are sourcing a custom aluminum die cast mounting base or another non-standard aluminum component, send us the drawings. We can review the casting structure, mounting features, machining areas and finishing requirements before the tooling is released.