Your HPDC die already has cooling channels.

You have adjusted the water flow. You have optimized the spray cycle. You may have even increased cooling time.

But one area of the die is still running too hot.

A core keeps soldering. An insert wears out much earlier than expected. A localized hot spot limits your cycle time. Or a casting area continues to show porosity despite process adjustments.

When conventional cooling cannot reach the area that needs cooling most, conformal cooling may be worth considering.

With metal additive manufacturing, a 3D printed mold insert can integrate cooling channels that follow the geometry of the cavity or core. This gives you more freedom to place cooling where conventional drilling cannot.

For high pressure die casting, the objective is not to make the cooling system more complicated.

The objective is to solve a specific thermal problem.

When Conventional Cooling Is No Longer Enough

Conventional cooling remains an effective and economical solution for many HPDC dies.

Straight drilled cooling channels are well understood, easy to maintain, and suitable for many relatively simple geometries.

The problem occurs when the die geometry and thermal load become more complicated.

You may encounter:

• A localized hot spot that cannot be reached effectively
• A deep or slender core that is difficult to cool
• Soldering that repeatedly occurs in the same location
• Excessive cooling time before ejection
• Uneven die temperatures
• Premature thermal fatigue or heat checking
• Insert wear concentrated in one area
• Solidification or porosity problems associated with local thermal conditions
• A cooling channel layout limited by drilling access

In these situations, simply adding another straight channel may not solve the underlying problem.

The question becomes:

Can the cooling channel be placed where the heat actually needs to be removed?

That is the basic idea behind conformal cooling.

What Is Conformal Cooling?

Conformal cooling is a cooling method in which internal cooling channels are designed to follow the geometry of the die casting mold cavity, core, or insert.

Instead of being restricted to straight drilled passages, the cooling channels can follow a three-dimensional path around critical areas of the die.

This is particularly useful when the cavity geometry contains:

• Deep cores
• Ribs
• Bosses
• Complex surfaces
• Thick sections
• Localized thermal loads

The advantage is not simply that the channel is curved.

The real advantage is greater control over channel location and channel-to-cavity distance.

A conventional drilled channel may be close to one section of the cavity but far away from another.

A conformal cooling channel can be designed to maintain a more controlled relationship with the cavity surface.

This can improve thermal management where conventional cooling has reached its practical limits.

Why Use 3D Printed Mold Inserts?

This is where additive manufacturing becomes particularly valuable.

Conformal cooling requires cooling channels with geometries that can be difficult—or impossible—to manufacture using conventional drilling.

A 3D printed mold insert allows the cooling channels to be designed inside the insert before the metal is printed.

The channel geometry is therefore not limited by the direction of a drill.

You can design channels to:

• Follow complex cavity surfaces
• Reach difficult cooling areas
• Maintain a controlled distance from the cavity
• Curve around cores
• Target localized hot spots
• Combine different cooling paths within a compact insert

For HPDC, this does not necessarily mean printing an entire die.

In many applications, the more practical solution is to replace only the problem area with a 3D printed conformal cooling insert.

Existing Die + New 3D Printed Insert

You may not need to redesign your entire die casting mold.

A typical approach can be:

Existing HPDC die → identify thermal problem → redesign the affected insert → add conformal cooling → 3D print the insert → CNC machine and finish → install in the die

This localized approach can reduce the amount of additive manufacturing required while focusing the technology where it can create the most value.

Conformal Cooling vs Conventional Cooling

The choice between conventional and conformal cooling should be based on the problem you are trying to solve.

Conventional Cooling	Conformal Cooling
Straight drilled channels	3D cooling channel paths
Limited by drilling access	Greater geometric freedom
Effective for many standard applications	Useful for complex thermal areas
Lower manufacturing complexity	Higher design and manufacturing requirements
Cooling layout follows machining limitations	Cooling layout follows thermal requirements
Difficult to cool some deep or complex areas	Can bring cooling closer to selected hot spots

This does not mean conformal cooling is always better.

If conventional cooling already provides sufficient thermal control, a conventional insert may be the better solution.

The value of a conformal cooling insert becomes clearer when conventional cooling is preventing you from achieving the required thermal performance.

The right question is:

Where does conventional cooling stop being effective, and can additive manufacturing solve that specific limitation?

How Can Conformal Cooling Reduce HPDC Cycle Time?

Cycle time is often one of the first reasons to investigate conformal cooling.

In HPDC, the casting needs to remain in the die long enough for critical areas to reach the required condition for ejection.

If a localized hot spot controls the cooling time, the entire cycle can be affected by one relatively small area of the die.

A conformal cooling channel can target that area directly.

Better heat removal may allow you to reduce the cooling portion of the cycle while maintaining the required casting quality and ejection conditions.

However, there is no universal conformal cooling cycle time reduction percentage.

The actual result depends on:

• Casting geometry
• Wall thickness
• Alloy
• Die temperature
• Cooling medium
• Coolant flow rate
• Cooling channel geometry
• Channel-to-cavity distance
• Spray cycle
• Ejection requirements
• Existing thermal conditions

If cooling is not the bottleneck, changing the cooling design will not necessarily produce a meaningful reduction in total cycle time.

If cooling is the bottleneck, however, a well-designed conformal cooling insert can directly target the limiting area.

That is why the design should begin with the thermal problem, not with a target percentage.

How Do Conformal Cooling Channels Improve Heat Transfer?

The main benefit comes from controlling where heat is removed.

A conventional channel may be relatively far from a hot spot because the drill cannot reach the required position.

The result can be:

Hot cavity surface → large thermal distance → cooling channel

With conformal cooling, the channel can be designed to follow the cavity more closely:

Hot cavity surface → controlled thermal distance → cooling channel

This can improve heat extraction from selected areas and help create a more uniform die temperature.

The effectiveness of the system still depends on:

• Cooling channel diameter
• Channel-to-cavity distance
• Coolant velocity
• Pressure
• Flow rate
• Cooling medium
• Insert material
• Channel geometry
• Thermal load

Therefore, conformal cooling channel design should be treated as an engineering problem rather than simply a 3D modeling exercise.

Can Conformal Cooling Extend Mold Life?

It can, particularly when excessive localized heat and thermal cycling are contributing to insert failure.

HPDC tooling is exposed to repeated thermal shock.

Localized temperature differences can contribute to:

• Thermal fatigue
• Heat checking
• Soldering
• Surface degradation
• Insert cracking
• Premature wear

If conformal cooling improves the thermal balance of the insert, it may reduce excessive thermal loading in critical areas.

But the result depends heavily on the specific die design and operating conditions.

A useful real-world example comes from an AMC/NADCA project involving conformally cooled inserts for a production HPDC application.

In the documented Ryobi Die Casting application, traditional inserts required replacement after approximately 10,000 shots. The conformally cooled 3D printed crown inserts subsequently lasted more than 90,000 shots.

The same case reported that porosity-related rejects decreased from 0.5% to 0.1%, while soldering was eliminated.

These results should not be treated as a guaranteed improvement for every HPDC die.

The important point is that the project demonstrated how improved thermal management can affect more than cooling time:

Thermal control → less localized overheating → less soldering and wear → longer insert life and improved production stability

AMC Case Study: 3D Printed Conformal Cooling Inserts in Production

The American Metalcasting Consortium, together with industry and research partners including NADCA and Ryobi Die Casting, investigated additive manufacturing for HPDC inserts with conformal cooling.

The project produced steel inserts with integrated cooling channels and tested them in a production die casting environment.

The documented design included:

• 3 mm cooling channels
• 2 mm minimum channel curvature
• 3 mm minimum wall thickness
• H13 and maraging steel powder options

The production results showed improved heat extraction and reduced insert wear. The heavy-duty transmission case application ultimately demonstrated more than 90,000 shots from the conformally cooled crown inserts compared with approximately 10,000 shots for the previous inserts.

This is one of the useful lessons from the case:

A conformal cooling insert does not need to replace the entire die to create value.

The technology can be concentrated in the area where thermal performance is limiting production.

Image source: AMC. If there are any concerns regarding the use of this image, please contact us and we will review or remove it as appropriate.

What Materials Are Used for 3D Printed Mold Inserts?

A 3D printed insert for HPDC must withstand demanding thermal and mechanical conditions.

The material needs to tolerate repeated thermal cycling while maintaining the required strength and dimensional stability.

Depending on the application, materials such as H13-type tool steel and maraging steel can be considered for additively manufactured HPDC inserts.

The AMC project evaluated both H13 printed powder and maraging steel powder for its conformally cooled inserts.

However, material selection is only one part of the solution.

The performance of a 3D printed mold insert also depends on:

Material → Printing → Heat Treatment → CNC Machining → Surface Treatment → Cooling Design

A good material cannot compensate for a poor cooling design.

Likewise, a well-designed cooling channel is only useful if the printed insert has the mechanical and metallurgical properties required for production.

Conformal Cooling Channel Design: What Matters?

A good conformal cooling channel design starts with the actual thermal load of the die.

Channel-to-Cavity Distance

The channel should be positioned close enough to provide effective cooling while leaving sufficient material around the passage.

There is no single distance that is suitable for every HPDC application.

Channel Diameter

Channel diameter affects:

• Flow rate
• Pressure loss
• Heat transfer
• Manufacturing feasibility
• Remaining insert wall thickness

The diameter should therefore be selected as part of the complete cooling system.

Channel Curvature

Curved channels are one of the key advantages of additive manufacturing.

They allow the cooling path to follow complex areas of the cavity instead of being limited to intersecting straight holes.

Wall Thickness

Sufficient material must remain between the cooling channel and the cavity surface to maintain insert strength and reliability.

The AMC case, for example, used a minimum wall thickness guideline of 3 mm for its specific printed inserts. This should not be interpreted as a universal specification for every HPDC insert.

Cooling Flow

A conformal channel does not automatically provide better cooling.

Coolant velocity, pressure, flow rate, and channel geometry all influence heat transfer.

The cooling system must therefore be designed as a complete system.

How Large Can a 3D Printed Mold Insert Be?

The practical size of a 3D printed mold insert depends on the additive manufacturing equipment, material, geometry, printing orientation, support strategy, and post-processing requirements.

More importantly, you do not necessarily need to print a large insert.

For many HPDC applications, the most economical solution is a localized insert.

For example:

Large conventional die + small 3D printed conformal cooling insert

This can make sense when a small area is responsible for:

• Excessive cooling time
• Repeated soldering
• Localized porosity
• Premature insert failure
• A persistent hot spot

Instead of changing the complete mold, you can focus the additive manufacturing cost on the area where the potential production benefit is highest.

Is Your HPDC Die a Good Candidate for Conformal Cooling?

You may want to investigate 3D printed mold inserts if several of the following conditions apply:

1. One area of the die consistently runs hot

You have a repeatable hot spot rather than a general die-temperature problem.

2. Cooling time is limiting production

The casting needs additional time in the die before ejection.

3. Conventional drilling cannot reach the problem area

The geometry prevents you from putting a conventional cooling channel where it is needed.

4. Soldering keeps occurring in the same location

The problem appears to be localized rather than random.

5. One insert fails much earlier than the rest of the die

The failure pattern may indicate a localized thermal or mechanical issue.

6. You are trying to improve thermal consistency

The die has significant temperature differences between areas that should perform similarly.

7. You have already tried conventional cooling improvements

If changing flow, drilling additional channels, or adjusting the process has not solved the problem, conformal cooling may be worth evaluating.

If your die matches several of these conditions, a conformal cooling insert may be a better solution than continuing to modify conventional cooling.

How We Develop 3D Printed Mold Inserts at Raidy Mold

At Raidy Mold, we do not start with the question:

“Where can we put a 3D printed cooling channel?”

We start with:

“What problem are you trying to solve?”

The process can be approached in several stages.

Step 1 — Review the Problem

We look at the area causing the issue:

• Hot spot
• Soldering
• Cooling time
• Insert failure
• Porosity
• Difficult core cooling

Step 2 — Review the Existing Die

We evaluate the existing insert geometry and conventional cooling layout.

The objective is to understand what conventional cooling can already achieve and where it reaches its limitations.

Step 3 — Determine Whether Conformal Cooling Makes Sense

Not every insert needs to be 3D printed.

If conventional machining can solve the problem effectively, it may remain the better option.

If conventional cooling cannot reach the required area, additive manufacturing becomes more attractive.

Step 4 — Design the Cooling Channels

The channel design can be developed around the cavity geometry and thermal requirements.

Key considerations include:

• Channel location
• Channel-to-cavity distance
• Diameter
• Curvature
• Wall thickness
• Flow requirements
• Insert strength

Step 5 — Manufacture the Insert

Once the design is validated, the insert can be produced through metal additive manufacturing and subsequently undergo the required heat treatment and machining operations.

Step 6 — Finish the Production Surface

The printed insert still needs to meet the dimensional and surface requirements of the HPDC die.

CNC machining, finishing, inspection, and any required surface treatment remain important parts of the process.

The final product is not simply a printed component.

It is a production-ready HPDC mold insert.

Why Not Just Drill More Cooling Channels?

This is one of the most common questions when evaluating conformal cooling.

If the die is running hot, why not simply add another conventional channel?

Sometimes that is exactly the right answer.

But drilling has physical limitations.

The drill must approach the area from a reachable direction. Complex channels may also require intersections, plugs, and additional machining operations.

You can eventually reach a point where adding another straight channel:

• Cannot reach the hot spot
• Removes too much material
• Creates unfavorable channel intersections
• Compromises insert strength
• Still leaves an uneven cooling distance

This is where additive manufacturing conformal cooling channels in molds becomes interesting.

Instead of asking:

“Where can the drill go?”

you can ask:

“Where should the cooling channel be?”

That change in design freedom is the fundamental advantage.

When Is a 3D Printed Mold Insert Worth the Investment?

A 3D printed insert generally costs more to engineer and manufacture than a conventional insert.

The decision therefore needs to be based on production economics.

Look beyond the insert price and consider:

Cycle time

Could better cooling reduce the cooling-limited portion of the cycle?

Scrap

Could improved thermal balance reduce thermally related defects?

Maintenance

Could better thermal control reduce soldering or polishing downtime?

Die life

Could reducing localized thermal loading extend insert life?

Downtime

How much production is lost when the problem insert requires repair or replacement?

A more expensive insert can be the lower-cost solution if it removes a recurring production problem.

A Practical Approach: Start With One Problem Area

You do not need to redesign the entire die to evaluate conformal cooling.

If you have one insert that consistently causes problems, start there.

For example:

One core runs hot → longer cooling time → soldering → frequent polishing → production downtime

Instead of redesigning the entire cooling system, you can investigate:

3D printed conformal cooling insert for that core

This makes the engineering decision easier to evaluate.

You can compare the new insert against the existing design using measurable production data such as:

• Cycle time
• Die temperature
• Cooling flow
• Scrap rate
• Soldering frequency
• Insert life
• Maintenance frequency

This is a much more practical way to evaluate conformal cooling than simply asking whether the technology is “better.”

3D Printed Mold Inserts for Your Next HPDC Project

If you have already tried conventional cooling improvements and still have a localized thermal problem, 3D printed mold inserts with conformal cooling may be worth evaluating.

You do not necessarily need a completely new die.

A localized insert can be designed to address the specific area where conventional cooling is limited.

Raidy Mold can review your existing insert geometry, cooling layout, and application requirements to determine whether additive manufacturing is technically and economically appropriate.

Have a Difficult Cooling Area in Your HPDC Die?

Send us the information you already have.

Useful information includes:

• 3D casting model
• Insert drawing
• Existing cooling layout
• Problem location
• Current cycle time
• Die temperature data, if available
• Photos of soldering, wear, or other damage

We can evaluate whether a conformal cooling insert is a practical solution and where the cooling channels could provide the greatest potential benefit.

You do not need to redesign the entire die before asking.

Sometimes the solution is one insert.

[Request a Conformal Cooling Insert Review]

A Raidy Mold Case: Comparing Conformal Cooling with Conventional Cooling

We also compared a 3D printed mold insert with conformal cooling channels against a conventional insert with standard spot cooling using MAGMA simulation.

The comparison showed a clear difference in thermal behavior. From filling 0% to 100%, the 3D printed insert maintained a temperature approximately 63.2–83.5°C lower than the conventional insert in the simulated area.

The hot spot analysis also showed that the product’s thermal node around the insert area was lower with the conformal cooling design, with the selected measurement points showing a difference of approximately 0.08–0.34 seconds.

This simulation is part of our approach to evaluating whether a 3D printed mold insert can provide a meaningful cooling advantage over a conventional insert before moving into production.

A detailed breakdown of this MAGMA simulation and the two cooling designs will be covered in a separate case study.→→ “How Can 3D-Printed Inserts Reduce HPDC Mold Risks?”

FAQ

What is conformal cooling in high pressure die casting?

Conformal cooling uses cooling channels designed to follow the geometry of an HPDC cavity, core, or insert. The channels can be positioned closer to critical thermal areas than conventional drilled channels allow.

What are 3D printed mold inserts?

3D printed mold inserts are metal tooling components manufactured using additive manufacturing. In HPDC, they can integrate internal cooling channels that would be difficult or impossible to produce through conventional machining.

Can conformal cooling reduce die casting cycle time?

It can reduce the cooling portion of the cycle when cooling is the limiting factor. The actual cycle time reduction depends on casting geometry, alloy, die temperature, cooling design, coolant flow, and production conditions.

Does conformal cooling extend mold life?

It can. Better thermal control may reduce localized overheating, thermal fatigue, soldering, and insert wear. Actual die-life improvement depends on the specific tooling and production conditions.

What materials can be used for 3D printed HPDC inserts?

H13-type tool steels and maraging steels are among the materials that can be considered for additively manufactured HPDC inserts. Material selection should be based on the thermal, mechanical, and production requirements of the application.

Is conformal cooling better than conventional cooling?

Not in every application. Conventional cooling remains highly effective for many die designs. Conformal cooling becomes more attractive when conventional drilling cannot provide sufficient cooling to a critical area.

Do I need to 3D print the entire die?

No. A localized 3D printed mold insert can be used in the area where conventional cooling is insufficient, while the rest of the die remains conventionally manufactured.

How do I know if my die is suitable for a conformal cooling insert?

Look for persistent localized hot spots, cooling-limited cycle time, recurring soldering, premature insert failure, difficult core cooling, or areas that cannot be reached effectively with conventional drilled channels. Your insert geometry can then be reviewed to determine whether additive manufacturing is practical.

Final Takeaway

Conformal cooling is not about adding more cooling. It is about putting cooling where you need it.

For HPDC dies with difficult thermal problems, a 3D printed mold insert can provide the design freedom needed to place cooling channels around complex geometry and closer to critical hot spots.

The potential result is better thermal control, more stable production, shorter cooling time where cooling is the bottleneck, less soldering, and potentially longer insert life.

But the best application is not necessarily the die with the most advanced cooling design.

It is the die where better thermal control can solve a measurable production problem.

If you have one area of your HPDC die that conventional cooling cannot solve, that may be the right place to start.

Send us your insert drawing or 3D model. Let’s evaluate whether a 3D printed conformal cooling insert can make a difference in your process.