Designing plastic equipment enclosures for 2027

A step-by-step guide for using heavy-gauge thermoforming effectively

Introduction

Product development is a “crawl, walk, run” experience. Teams must strategically address critical process factors early in development to avoid mistakes and production delays. 

Many OEMs turn to heavy-gauge thermoforming for equipment enclosures. These are large, thermoformed parts that balance aesthetics, durability in harsh environments, serviceability, and manufacturability. 

Production volumes for industries that sell less than consumer levels favor thermoforming. Advanced thermoforming processes like pressure forming offer design flexibility, lower upfront tooling investment, and faster iteration compared to injection molding. 

However, successful enclosures require good industrial design that takes advantage of the manufacturing process capabilities. This guide gives you a practical, step-by-step approach to designing complex thermoformed enclosures. 

Ultimately, it’s important to collaborate with an experienced heavy gauge thermoformer who can help you through these steps to go from prototype through production launch.

12 steps for successful design

OEMs face some key challenges and design-for-manufacturing (DFM) decisions during development. Address these 12 steps with additional insight from the Profile Design Guide and technical articles. 

1. Treat enclosures as functional systems.

Equipment housings don’t just cover electronics. These parts provide heat management and signal shielding, plus enable safe human interaction. Start by mapping out electrical clearance, airflow, mounting points, stress loads, and service access. Then consider aesthetics and branding.

2. Choose thermoforming for the right reasons.

Use heavy-gauge thermoforming for your large, durable parts in low-to-mid-volumes. An often-overlooked reason to use thermoforming is speed to market, which can buy you time to make adjustments. Pressure forming delivers sharp detail and molded-in textures, while vacuum forming works well for utility components. 

3. Select materials around performance, compliance, and availability.

Match your material choice to the application environment. Identify the resin that fits your needs, rather than a brand name.
Factors to evaluate include:

• Impact strength
• Rigidity
• Chemical resistance 
• Surface finish cleanability 
• UL flame rating
• Color stability
• Recyclability and sustainability requirements
• Availability

Specifying the resin rather than a brand name protects your supply chain, so you aren’t left vulnerable to “single source” issues. Learn more with Profile’s Material Selector. It helps to pick a thermoformer with advanced material expertise. 

4. Design for draw and wall distribution.

Review your part designs with an experienced thermoforming engineer to highlight areas that could result in thin walls or weak corners. Discuss these challenges to find the most efficient changes that will ensure your part’s durability and long-term quality. See the Design Guide for detailed advice for making improvements. 

5. Use draft deliberately.

Add draft wherever the part pulls from the tool to protect the surface finish, reduce part stress, and improve repeatability. Increase draft on deep walls, textured surfaces, and cosmetic faces. Avoid near-vertical walls unless your thermoformer confirms the tool, process, and release strategy.

6. Control undercuts carefully.

Use undercuts only when they add real value. Design features like hidden parting lines or wraparound edges improve stiffness. However, undercuts require retractable mold components, which adds cost. Design undercuts so the vendor can form, release, and trim the part without distortion. Find more detailed info in the Design Guide.

7. Set realistic tolerances.

Thermoforming requires different tolerances than injection molding or stamped or machined metal, so separate cosmetic surfaces from functional interfaces. Keep tolerances a bit looser in general but tight for critical edges, mating flanges, inserts or mounting bosses, and display or connector openings. See the Profile tolerance guide for specifics.

8. Plan CNC trimming from the start.

Thermoforming allows you to adjust the CNC trim edges without adding tooling costs. Many customers designing their next generation of device covers simply alter the trim program to accommodate changes. CNC trimming impacts final geometry, edge quality, and repeatability. Stable trim fixtures are critical for consistent edges.

9. Simplify assemblies before adding hardware.

Use molded forms for stiffness but avoid forcing thermoformed parts to act like precision structural frames. Add inserts, adhesive-bonded blocks, or machined structures to support loads. Design service panels, seams, and fastener locations so technicians can remove covers without cracking tabs or scratching user-facing surfaces.

10. Choose a vendor that lowers your risk.

Ask the right questions when selecting your partner for equipment enclosures. Lean on experienced vendors that review CAD drawings early and challenge risky features. Can they prototype, then ramp production? Capabilities and capacity, material sourcing, CNC trimming and assembly/finishing, inspection and quality systems make a difference. A quality thermoformer provides good communications as well as agile manufacturing.

11. Prototype risky features first.

Inexpensive prototype tools allow you to sample critical areas of a design. You can adjust before making production tooling with the final surface texture. Material behavior like chemical resistance can be tested on the raw plastic sheet. 

12. Ramp up with measurable controls.

Resolve your material spec, tooling, trim program, inspection thresholds, cosmetic criteria, packaging, and change-control process during development. Quality processes cover all aspects of production. Run pilot builds at production intent to measure part fit, finish, assembly time, trim quality, and part-to-part variation. You’ll discover issues during the production ramp, instead of after launch. 

Conclusion: Scale with confidence

Designing successful equipment enclosures requires more than picking a material and sending CAD files to a thermoformer. Reliable programs start with DFM-driven decisions to reduce risk, accelerate validation, and achieve long-term production scalability. 

Some aspects of your project can be considered up front, then address details and strategies early in development. A strong DFM process makes it easier to identify a capable heavy-gauge thermoforming partner. You want someone who can deliver consistent quality through prototype phases to full production ramps.

Are you developing next-gen equipment? For durable thermoformed covers and enclosures, aligning your design intent with manufacturing reality is the fastest path to a successful launch.