High-Density Skived Heat Sink Module for an EV Charging Project
A manufacturing case involving thin, tall skived fins, approximately 0.5 mm fin thickness, 0.5 mm fin gap and 33 mm fin height — with particularly strict requirements for fin verticality, channel consistency and final assembly.
Why This EV Charging Heat Sink Was More Difficult Than the Dimensions Suggest
High-power charging equipment contains power electronic components that generate significant heat inside a limited installation space. In this project, the customer required a custom air-cooled thermal module built from two separately manufactured skived heat sinks and surrounding sheet-metal structures.
At first glance, the individual dimensions may not appear unusual. The real manufacturing challenge came from their combination: approximately 0.5 mm thin fins, only about 0.5 mm between adjacent fins, a fin height of around 33 mm, and a very strict requirement for fin straightness and verticality.
The two skived heat sink sections were positioned with their fin arrays facing toward the internal cooling area and then integrated into the final module. Because the fin channels were narrow, maintaining a consistent fin array was important both for airflow and for mechanical assembly.
When tall, closely spaced fins need to remain parallel over the complete heat sink, small variations in the skiving process can become increasingly important. This matters not only for appearance, but also for airflow channels, assembly accuracy and repeatable thermal performance.
Two Opposing High-Density Skived Heat Sinks Form the Cooling Module
Unlike a conventional single heat sink, this project used two separately manufactured skived heat sink sections within a larger mechanical assembly.
The high-density fin arrays faced toward the internal cooling region, while sheet-metal parts surrounded the assembly and formed the external module structure.
This arrangement increased the importance of controlling the geometry of both heat sinks. Fin deformation on either component could affect channel consistency, internal clearance or final assembly fit.
- Approximately 0.5 mm fin thickness
- Approximately 0.5 mm gap between adjacent fins
- Approximately 33 mm fin height
- Two independent precision-skived heat sink sections
- Fin arrays facing toward the internal cooling region
- Sheet-metal structure surrounding the assembly
- Closely controlled fin straightness and verticality
- Dimensional control for final module assembly
Simplified two-piece skived heat sink module with surrounding sheet-metal enclosure — not to scale.
Why Fin Verticality Matters in a High-Density Heat Sink
With only a narrow space between neighboring fins, fin position becomes part of the functional geometry of the cooling system.
Airflow Channel Consistency
If a tall fin leans toward an adjacent fin, the local channel becomes narrower. With a dense fin array, maintaining consistent channels helps preserve the intended airflow path through the heat sink.
Pressure Drop & Air Distribution
Irregular channels can introduce additional flow resistance in specific areas. For forced-air cooling designs, geometry and airflow therefore need to be considered together rather than evaluating fin density alone.
Final Module Assembly
This project required two heat sink sections to be integrated with surrounding sheet-metal components. Excessive fin deformation could create mechanical interference or inconsistencies during final assembly.
Project Manufacturing Focus
Controlling the Fin Array Starts Before Final Inspection
For high-density skived heat sinks, final dimensional inspection is important, but consistent fin geometry cannot be created by inspection alone.
Stable manufacturing requires control throughout the process, including raw material condition, workholding, skiving machine setup, cutting tool condition, process parameters and handling after the fins are formed.
This becomes more important as fins become thinner, taller and more closely spaced. Improper handling during downstream machining, inspection or assembly can also deform an otherwise acceptable fin array.
In a multi-component thermal module, dimensional stability must also be maintained through final mechanical integration. A heat sink that meets individual fin dimensions but cannot maintain consistent geometry during assembly may still create problems at the module level.
From Drawing Review to Thermal Module Assembly
Drawing-based heat sink projects are reviewed around both thermal geometry and manufacturing requirements before production.
Drawing Review
Review fin geometry, base dimensions, critical tolerances, mounting features and final assembly requirements.
Process Planning
Evaluate skiving direction, workholding, machining sequence and potential deformation risks.
Precision Skiving
Produce the high-density fin arrays while controlling fin formation, spacing, straightness and consistency.
Inspection
Check key dimensions, fin geometry, verticality, base features and other drawing-defined requirements.
Module Assembly
Integrate both skived heat sink sections with the required sheet-metal structure and verify final fit.
What Should Be Inspected on a Tall, Thin-Fin Skived Heat Sink?
Heat sink inspection should follow the customer drawing and the functional requirements of the complete assembly. For a dense fin structure like this one, several characteristics deserve particular attention.
Fin Geometry
- Fin thickness
- Fin gap / spacing
- Fin height
- Fin straightness
- Fin verticality
Machined Features
- Overall dimensions
- Mounting features
- Hole positions
- Critical base dimensions
- Drawing tolerances
Module Assembly
- Two-part alignment
- Sheet-metal fit
- Mechanical clearance
- Fin protection
- Final module dimensions
High Fin Density Is Only Useful When the Geometry Can Be Manufactured Consistently
Increasing fin density can provide more heat transfer surface area inside a limited envelope, which is one reason skived heat sinks are frequently considered for compact power electronics.
However, more fins do not automatically mean better cooling. Fin thickness, fin height, channel width, airflow, pressure drop, fan capability and available installation space all interact.
In practical manufacturing, engineers also need to consider whether the proposed geometry can remain stable through machining, inspection, handling and final assembly.
This becomes especially important when multiple heat sink sections and structural components must work together as one finished thermal module.
Where Similar High-Density Skived Heat Sink Modules May Be Used
Similar manufacturing approaches can be relevant to compact, high-power systems where forced-air thermal performance and limited installation space drive the need for dense fin structures.
Frequently Asked Questions About EV Charging Heat Sinks
Why use a skived heat sink for EV charging power electronics?
Skiving can create thin, closely spaced fins directly from the heat sink base. This gives designers more freedom to create dense fin arrays for forced-air cooling applications where conventional extrusion geometry may be restrictive. The final fin geometry should always be evaluated together with airflow and pressure-drop requirements.
Can skived heat sink fins be approximately 0.5 mm thick?
Yes. BY Thermal manufactures custom skived heat sinks with different fin thicknesses and geometries. However, manufacturability depends on the complete design, including material, fin height, fin length, fin spacing, heat sink width, base geometry and dimensional requirements. A drawing review is recommended before confirming production capability.
Why is fin verticality important?
For tall fins with narrow spacing, excessive leaning or deformation can change local airflow channels and may create mechanical interference during assembly. Fin verticality can therefore become an important functional manufacturing requirement rather than simply a cosmetic one.
Can two skived heat sinks be assembled into one thermal module?
Yes. Depending on the application, multiple heat sink sections can be integrated with CNC-machined parts, sheet-metal structures, heat pipes, fans or other components. Assembly requirements should be included in the 2D drawing or 3D model so dimensional relationships can be reviewed before production.
What information should I send for a custom EV charger heat sink quotation?
A 2D drawing and 3D model are preferred. Please also provide material, prototype and production quantity, critical tolerances, surface finish, assembly requirements and target delivery schedule. If thermal optimization is required, heat load, heat-source location, airflow, ambient temperature and allowable component temperature are also useful.
Developing a Heat Sink for an EV Charger or Power Module?
Send us your 2D drawing, 3D model or thermal requirements. Our team can review the fin geometry, material, CNC features, assembly requirements and manufacturing feasibility before quotation.
Custom manufacturing based on customer drawings. Prototype and production requirements are reviewed project by project.