Outsourcing box build electronics can streamline production and improve time to market, but it also introduces risk if the project isn’t well-defined from the beginning. A box build can refer to complete system integration, where all electronic components come together, or it may involve subassemblies that are part of a larger unit. Today’s products are highly complex, often including multiple printed circuit board assemblies (PCBA), RF cable assemblies, and intricate wire harnesses. Because they tie together multiple engineering disciplines and suppliers, they can get off track quickly without the right level of preparation and communication.
Here’s a look at the most common pitfalls in box build electronics projects, and what can be done to avoid them
Incomplete or Inaccurate BOMs
One of the most common issues contract manufacturers face is a bill of materials (BOM) that lacks detail or includes outdated part numbers. In box build projects, BOMs typically need to include not only electrical components but also mechanical parts, fasteners, wiring, connectors, adhesives, and enclosures. If parts are obsolete, the manufacturer may have to source new components, which can extend delivery times. If the BOM is unclear or fragmented across multiple documents, the risk of incorrect builds increases.
How to avoid it:
Submit a consolidated and up-to-date BOM that includes manufacturer part numbers, approved alternatives, and specifications for all mechanical parts. Include revision history and clarify any customer-supplied components. Keep up to date on components facing obsolescence so replacements can be sourced before a build is required.
Ambiguous Mechanical Drawings or Assembly Instructions
Even when the electrical side is well-documented, the mechanical aspect is often overlooked. Box build projects depend on clear mechanical drawings, enclosure specs, wiring diagrams, and cable routing plans. If these are vague or missing, the manufacturer is forced to guess or request clarification mid-build—both of which create delays.
How to avoid it:
Provide complete 2D and 3D mechanical drawings, exploded views of assemblies, and labeling conventions. Include photos of existing builds if available, and define torque specs, fit tolerances, and wiring paths.
Overlooking Test Requirements
Don’t treat functional and final testing as an afterthought in your box build projects. Without defined test procedures, the contract manufacturer may not have the right equipment or setup to validate performance, especially if the build includes software, sensors, or moving parts.
How to avoid it:
Define test protocols early. Share test fixtures, functional test scripts, power-up sequences, and acceptance criteria. If the test environment is complex, work with the contract manufacturer to co-develop fixtures or simulation tools.
Late Design Changes
Engineering change orders (ECOs) are part of the process, but late-stage changes, especially after tooling or procurement, can throw off schedules, increase costs, and lead to rework. This is particularly disruptive in box build projects where electrical, mechanical, and software components are tightly integrated.
How to avoid it:
Freeze the design as early as possible. If changes are necessary, consolidate them into batches and clearly mark revision levels. Use a change management system that your contract manufacturer can access and track.
Misaligned Expectations on Packaging and Logistics
Final packaging may seem like a minor detail, but improper packaging can damage the product or create compliance issues for international shipments. In some cases, the product must meet specific labeling or ESD protection standards.
How to avoid it:
Specify packaging materials, label formats, and ESD protection requirements up front. If your product will ship directly from the contract manufacturer to end users, provide clear kitting and fulfillment instructions.
Limited Early Collaboration
Many box build failures stem from a lack of early engagement between the OEM and contract manufacturer. Waiting until the design is locked before engaging the CM removes opportunities for design for assembly (DFA), cost optimization, and feedback on component lead times.
How to avoid it:
Involve your contract manufacturer during the design phase. They can flag sourcing risks, suggest assembly-friendly changes, and plan tooling or fixtures to improve efficiency and quality.
Early Collaboration for Successful Box Build Electronic Projects
Box build electronics projects run more smoothly when OEMs and contract manufacturers operate with transparency and shared expectations. Most issues trace back to unclear documentation, last-minute changes, or assuming the CM will fill in the gaps. The more detailed and accurate the handoff, the more consistent and scalable the final product will be.
If your next build involves multiple sub-assemblies, wiring, enclosures, or integrated testing, a strong foundation of documentation and early communication will save time and cost before the first unit even hits the line.
Trust Siemens Manufacturing for Box Build Assemblies
Take the first step towards a seamless box build electronic project by partnering with Siemens Manufacturing. Ensure your product’s success with our unparalleled expertise and commitment to quality. Contact us today to discuss your needs and discover how we can help you achieve your goals efficiently and effectively.