How to Reduce CNC Machining and Process Steps for Complex Aluminum Parts

For procurement teams and engineers working with complex aluminum components, the cost problem often begins long before a supplier sends a quotation.

A part may look relatively simple after machining, yet the manufacturing route behind it can involve a large starting billet, extensive material removal, long machine time and several separate production steps.

At prototype volume, machining directly from plate or billet can make perfect sense.

But as production volume grows, the same route can become increasingly inefficient.

The question is no longer simply:

Can this part be machined?

A better question is:

Does so much of this part really need to be created by machining?

For suitable aluminum components, moving more of the geometry into the forming stage can reduce unnecessary CNC work and simplify the overall manufacturing route.

This is one of the main problems Beigong developed its integrated cast-forging technology to solve.

Why CNC Machining Becomes Expensive for Complex Aluminum Parts

CNC machining is extremely valuable for precision.

It is particularly suitable for critical mounting surfaces, holes, interfaces, sealing areas and dimensions that require tight control.

The problem begins when CNC machining is used not only for precision finishing, but also to create most of the component geometry from a large piece of aluminum.

Imagine a structural component with:

large openings,

curved walls,

mounting bosses,

reinforced areas,

deep pockets,

and an irregular outer profile.

If the entire part begins as plate or billet, a large percentage of the original material may need to be removed before the final geometry appears.

That creates several hidden costs.

More aluminum must be purchased than remains in the finished component.

More machine capacity is consumed removing material that will never become part of the product.

More cutting-tool time is required.

More chips must be handled and recycled.

Longer machining cycles can also become a production bottleneck when volumes increase.

For a purchasing team, this eventually becomes a total-cost problem.

For an engineer, it becomes a manufacturability problem.

Material Waste Is Only Part of the Problem

It is easy to focus only on the value of the removed aluminum.

But material utilization is only one part of the manufacturing equation.

Every extra machining operation also consumes:

machine capacity,

cutting tools,

fixtures,

energy,

operator time,

inspection time,

and production lead time.

This means a component can be expensive even when the raw material itself is not particularly expensive.

The manufacturing route is often the real cost driver.

That is why reducing the amount of material removed after forming can have a much wider effect than simply reducing scrap.

The objective should be to bring the part closer to its final geometry before precision machining begins.

This is commonly described as a near-net-shape manufacturing approach.

Why Conventional Casting Does Not Solve Every Problem

A natural response might be:

Why not simply cast the component?

For many aluminum products, conventional casting is an excellent solution.

It can create complex geometry efficiently and reduce machining compared with billet production.

But not every structural aluminum part is well suited to a conventional casting route.

Depending on the alloy, geometry and application requirements, engineers may encounter challenges related to:

internal structure,

local load-bearing areas,

heat-treatment requirements,

material selection,

forming defects,

or the mechanical demands of the final component.

At the other end of the spectrum, conventional forging can provide strong material structures, but complex geometry can make the process more difficult or require additional forming and machining stages.

This creates a common engineering dilemma:

Casting offers geometric freedom.

Forging offers structural advantages.

Machining offers precision and flexibility.

But using each as a completely separate process can create a long and expensive manufacturing chain.

The Problem With a Separate Cast-Then-Forge Route

In conventional cast-forged production, casting and forging may be handled as separate stages.

A preform is produced first.

It then has to be transferred into another forming stage for forging.

Depending on the component and production route, this can mean additional:

handling,

process transfers,

heating,

tooling,

equipment,

work-in-process,

and production control.

Each individual operation may be technically proven.

But when the complete manufacturing chain is considered, the process can become longer than necessary.

Beigong's integrated cast-forging technology was developed around a different idea:

What if casting and subsequent pressure forming could be coordinated within a shorter, integrated manufacturing route?

What Integrated Cast-Forging Changes

Integrated cast-forging is not simply conventional casting followed by a completely separate conventional forging operation.

The process combines controlled metal filling and pressure deformation within an integrated forming system.

The forming equipment, tooling and process are designed around this sequence.

The objective is to obtain more of the required component geometry during forming while also applying pressure and deformation where structural improvement is required.

For the customer, the most important point is not the name of the process.

It is what the process can change in the manufacturing route.

More Geometry Can Be Created Before CNC

Instead of starting with a large solid block and removing most of it, the forming stage can produce a blank much closer to the required component shape.

CNC machining is still used.

But its role changes.

Instead of creating the entire part, machining can concentrate on the areas where machining provides the most value:

critical interfaces,

precision holes,

mounting surfaces,

threads,

sealing surfaces,

and final dimensional control.

This is a very different use of CNC capacity.

Fewer Unnecessary Process Steps

When more forming functions can be coordinated within one manufacturing route, the number of separate operations can also be reduced.

The value is not simply that one machine performs more work.

The larger benefit is the possibility of simplifying the whole process chain.

For procurement teams, fewer process stages can mean fewer cost drivers and fewer production handoffs.

For manufacturing engineers, it can mean a more direct route from alloy to near-net blank to finished component.

For product developers, it creates another manufacturing option when the current design is trapped between casting limitations, difficult forging geometry and excessive machining.

A Real Manufacturing Problem: 6061 Parts Machined From Plate

This is not only a theoretical manufacturing discussion.

Beigong has worked on 6061 aluminum components that were originally produced primarily through CNC machining from plate.

The existing route was technically workable.

The problem was efficiency.

Too much of the final geometry depended on material removal.

By introducing an integrated cast-forging route, the component could be formed much closer to its finished shape before final machining.

The result was improved material utilization, reduced downstream machining and a shorter, more economical manufacturing route.

Examples in Beigong's development work include bracket-type components and oil-valve-base components.

The important lesson is not the individual component.

It is the manufacturing pattern behind it.

When a significant amount of expensive machine time is being used simply to remove aluminum, the component may be a candidate for a different forming strategy.

When Should You Consider Changing the Manufacturing Route?

A procurement manager or engineer should consider reviewing the manufacturing process when several of the following conditions appear together.

The component is machined from a much larger plate, billet or block.

A large percentage of the starting material becomes chips.

CNC cycle time is becoming a significant part of unit cost.

The geometry contains large cavities, curved sections or features that could potentially be formed instead of machined.

Production volume is increasing.

The component needs both complex geometry and structural performance.

Conventional casting is not meeting the material or application requirements.

Traditional forging has difficulty producing the required integrated geometry.

The current production route contains too many separate forming and machining operations.

In these situations, continuing to negotiate only the CNC hourly rate may not solve the real problem.

The bigger opportunity may be to redesign the manufacturing route.

Procurement Should Compare Total Manufacturing Cost, Not Only Process Price

This distinction is particularly important for sourcing teams.

Supplier A may offer a lower CNC hourly rate.

Supplier B may offer a lower material price.

But neither automatically creates the lowest finished-part cost.

A more useful comparison considers the complete route:

How much material enters the process?

How much material is removed?

How many separate forming steps are required?

How much downstream CNC machining remains?

How complex is the tooling strategy?

How repeatable is the process at production volume?

How many suppliers or production transfers are involved?

How easily can the process scale if annual demand increases?

The lowest individual operation price does not always produce the lowest total manufacturing cost.

This is why early collaboration between procurement, product development and manufacturing engineering can create significantly more value than simply requesting another machining quotation.

Engineers Should Think About Manufacturability Earlier

The same principle applies during product development.

If a component is designed first and the manufacturing process is considered only after the geometry is frozen, engineers may unintentionally create a part that depends on extensive machining.

A better approach is to evaluate manufacturing options earlier.

Questions worth asking include:

Can this cavity be formed instead of machined?

Can the outer geometry be produced closer to net shape?

Which surfaces genuinely require CNC precision?

Where does the component actually carry load?

Which areas need additional structural reinforcement?

Can several individual features be integrated into one formed component?

Can the manufacturing route be simplified without changing the functional requirements?

These questions can affect total product cost long before purchasing begins price negotiations.

Integrated Cast-Forging Is Not the Best Choice for Every Part

A good manufacturing solution is not about forcing every component into one technology.

Simple low-volume parts may still be most economical to machine directly.

Some geometries are perfectly suited to conventional casting.

Other components are ideal forging candidates.

Integrated cast-forging becomes most interesting when a part sits between these conventional routes.

Typical candidates are components that combine:

complex geometry,

significant material removal,

structural requirements,

lightweight design goals,

and production volumes that justify dedicated forming development.

The objective is therefore not to replace CNC machining.

It is to use CNC machining more intelligently.

From Machining a Shape to Engineering a Manufacturing Route

There is an important mindset change behind this approach.

A conventional question is:

How can we machine this part more cheaply?

The better engineering question may be:

How much of this part should be machined at all?

Once that question is asked, the design team can begin separating features into two groups.

Features that should be created during forming.

And features that genuinely need precision machining.

That is where near-net-shape manufacturing can create value.

Beigong's integrated cast-forging technology was developed specifically around this challenge: combining complex aluminum forming with pressure deformation in a shorter manufacturing route, so that downstream machining can focus on precision rather than creating the majority of the component.

Have a Part With Too Much CNC Machining?

If your aluminum component currently requires extensive material removal, long CNC cycles or multiple separate manufacturing stages, the first step does not need to be a complete redesign.

Start with a manufacturing feasibility review.

Send Beigong:

your drawing or 3D model,

the target aluminum alloy,

the component application,

critical dimensions and interfaces,

current manufacturing process,

estimated production volume,

and the manufacturing problem you are trying to solve.

Our engineering team can review whether the component is suitable for integrated cast-forging and identify where the current process may be simplified.

You do not necessarily need a cheaper machining supplier.

You may need a better manufacturing route.