Key Takeaway: Large plastic electrical enclosures introduce unique risks tied to size, structure, and process control. OEMs that address material behavior, tooling strategy, and manufacturability early — with an experienced large-part molder — reduce warpage, improve consistency, and protect long-term program performance.
Large plastic electrical enclosures are far more than protective housings. In industrial and electrical systems, they serve as structural components that must maintain dimensional stability, protect internal systems, and perform reliably across long service lives. As enclosure size increases, so does the complexity of designing and manufacturing parts that meet mechanical, environmental, and production requirements without introducing unnecessary risk. OEM’s of medical devices, lab equipment, communications, safety and security equipment as well as industrial controls must address these engineering challenges during new product development.
OEMs often encounter challenges related to structural rigidity, tolerance control across large footprints, material behavior at scale, and long-term durability. Addressing these challenges requires more than theoretical design rules; it demands practical experience executing large-part programs in real production environments.
This article explores how large plastic electrical enclosures are successfully engineered and manufactured in practice, and how Ferriot’s experience with large-part injection molding, engineered thermoplastics, and integrated secondary services helps OEMs reduce risk before tooling begins.
Why Large Plastic Electrical Enclosures Present Unique Engineering Challenges
As plastic electrical enclosures increase in size, design and manufacturing complexity rises quickly. Larger footprints introduce challenges that don’t exist at smaller scales and must be addressed deliberately to avoid performance and production issues.
Key challenges OEMs face with large plastic electrical enclosures include:
- Increased risk of warpage, sink, and deflection: Longer flow lengths, thicker sections, and uneven cooling make large parts more sensitive to material behavior and process variation.
- Compounding tolerance stack-up across large footprints: Dimensional variation that might be negligible on small housings can create fitment, alignment, or assembly problems at scale.
- Balancing structural strength with accessibility: Doors, panels, mounting points, and service access features introduce localized stress areas that must remain stable through repeated use.
- Environmental and operating exposure: Industrial electrical enclosures often face temperature swings, vibration, and contaminants, requiring designs that protect internal components without sacrificing manufacturability.
Successfully navigating these challenges requires experience executing large-part programs in real production environments. Ferriot supports OEMs producing large-format electrical enclosures by applying disciplined material selection, tooling strategy, and process control to deliver consistent, reliable results at scale.
Material Selection for Large Plastic Electrical Enclosures
Material behavior becomes increasingly important as part size grows. Ferriot commonly supports large plastic electrical enclosures using engineered thermoplastics such as polycarbonate (PC), PC/ABS blends, and glass-filled materials where appropriate, depending on structural and environmental requirements. Cosmetic requirements and user experience must also be considered where color, finish and texture are important.
Each material presents tradeoffs. Stiffer materials may improve rigidity but increase warpage risk if not processed correctly. Tougher blends can enhance impact resistance while affecting flow length and cooling behavior. At larger scales, shrink rate consistency and thermal response play a critical role in achieving dimensional stability. Parts may require secondary services to provide the desired cosmetic appearance.
Ferriot’s approach emphasizes materials with proven performance in large-format applications and consistent supply chains to support repeat production. Material traceability and processing consistency are key factors in maintaining long-term program stability, particularly for enclosures produced across extended product lifecycles.
Structural Design Strategies That Improve Performance and Manufacturability
Effective structural design is essential for large plastic electrical enclosures. Features such as ribbing, optimized wall thickness, and internal reinforcement help increase stiffness without unnecessary material use. However, these features must be designed with moldability in mind to avoid sink, uneven cooling, or extended cycle times.
Integrating mounting points, bosses, and fastening features directly into the molded enclosure can reduce secondary operations and improve assembly efficiency. At large scales, even small design inefficiencies can translate into significant cost or quality impacts.
Early Design for Manufacturability (DFM) collaboration is especially important for large parts. Ferriot’s in-house engineering team works with OEMs early in development to evaluate structural features, predict material behavior, and refine designs before tooling begins, helping prevent costly revisions later in the program.
Tooling and Process Considerations for Large Enclosures
Tooling for large plastic electrical enclosures presents its own set of challenges. Managing material fill across long flow lengths, designing effective cooling systems, and ensuring consistent ejection require specialized tooling expertise. Small variances in tooling design can lead to uneven shrinkage or extended cycle times when producing large parts.
In some applications, structural foam molding may be considered to increase stiffness while reducing part weight, where Ferriot applies the process appropriately based on part geometry and performance needs. Regardless of process selection, maintaining repeatability and process control is critical to achieving consistent results across production volumes.
Ferriot’s experience with large-format molds and disciplined process development helps OEMs maintain quality and predictability across long production runs.
Adding Value Through Integrated Secondary Services
Large plastic electrical enclosures often require additional finishing or assembly steps to meet end-use requirements. Ferriot provides production-grade painting and decorating, as well as assembly and subassembly services, to support enclosure programs without introducing additional vendor complexity.
Managing molding, secondary services, and assembly under one roof improves quality consistency and simplifies logistics. OEMs benefit from fewer handoffs, tighter schedule control, and clearer accountability, which is particularly valuable for large, high-visibility enclosure programs.
Designing for Long-Term Reliability and Program Success
Large enclosure programs rarely remain static. Design revisions, volume changes, and lifecycle extensions are common. Effective program management ensures these changes are handled without disrupting production or compromising quality.
Ferriot combines large-part injection molding expertise with in-house engineering, secondary services, and program management to support complex enclosure programs from early design through long-term production.
