8 Common Mistakes You Must Avoid When Placing a PCB Assembly Order
- Harshit Shah
- 14 minutes ago
- 5 min read
Placing a PCB assembly order is a critical step in turning your design into a working product. But even experienced OEMs run into problems when key details are missed or assumptions are made during the ordering process. A small mistake at the start can lead to delays, extra costs, or even failed boards.
The good news? Most of these issues are easy to avoid once you know where things typically go wrong.
In this guide, we’ll walk through the 8 most common mistakes to avoid when you placing PCB assembly order. These aren’t just technical slip-ups they’re real-world problems we see time and time again. Whether you’re building a prototype or moving into full production, catching these early can save you time, money, and a lot of frustration.
Key Takeaways
Always double-check your design files, especially your BOM, Gerber, and centroid files.
A DFM review can save time and money by catching issues before production.
Choose your PCB materials based on the product’s performance and environment.
Plan your component sourcing early to avoid lead time delays and part shortages.
Define all project requirements clearly, including testing and delivery expectations.
Don’t choose your electronics contract manufacturer based only on cost.
Include the right testing procedures to ensure board functionality and quality.
Keep communication clear, consistent, and responsive throughout the PCB assembly process.
Table of Contents
What Are the Most 8 Common PCB Assembly Ordering Mistakes?
Below are the 8 key mistakes that often cause problems during the order of PCB assembly. If you catch these early, you’ll avoid delays, confusion, and costly revisions.
1. Submitting Incomplete or Incorrect Design Files
One of the most frequent mistakes is sending files that are wrong or missing details. Your entire order depends on these files being accurate and complete.
What can go wrong:
Outdated or missing Gerber files can result in incorrect boards.
The Bill of Materials (BOM) may have missing parts or unclear descriptions.
Pick-and-Place (centroid) files may be left out, slowing down assembly.
Lack of assembly drawings confuses component orientation or placement.
Poor version control leads to mismatched files from different revisions.
Before placing your PCB assembly order, double-check everything. Keep your BOM, Gerber, centroid files, and notes in sync.
2. Ignoring Design for Manufacturing (DFM) Requirements
Skipping a DFM review is one of the most overlooked PCBA ordering mistakes. Just because a design works in your CAD software doesn’t mean it will be easy to manufacture.
Common issues:
Components are placed too close together.
Trace widths, spacing, and routing don’t follow assembly guidelines.
Improper Drill sizes or hole tolerances are not suitable for production.
Misaligned solder mask or silkscreen layers affect quality.
No DFM review is done before sending files for assembly.
Work with a electronics contract manufacturer that offers DFM feedback to help identify problems before they result in time or financial losses.
3. Picking the Wrong Materials, Finishes, or Components
The materials and components you choose can impact the board’s performance, cost, and lifespan.
What to avoid:
Using the wrong PCB substrate, such as FR4, when aluminum or high-Tg is required.
Selecting the wrong copper thickness, which can cause performance issues.
Choosing an unsuitable surface finish, such as HASL instead of ENIG or OSP.
Including hard-to-source or obsolete PCB components.
Designing with incorrect footprints or tolerances that don’t match real parts.
Discuss materials and finishes with your supplier early to avoid these PCB assembly process mistakes.
You May Also Read: How to Select the Right Electronic Components
4. Weak Component Sourcing and BOM Planning
Poor sourcing can delay production and increase your costs. Your electronics contract manufacturer needs a clear and complete BOM to do their job well.
Key problems:
Not checking component availability or lead times.
Leaving out part numbers or backup part options.
Going with the cheapest vendor instead of a trusted suppliers.
Ignoring compliance like RoHS or other regulations.
Plan your BOM carefully to avoid delays and get an accurate PCB assembly quote from the start.
5. Not Defining Clear Project Requirements & Objectives
When project details aren’t clear, PCB assembly results may not match your expectations. Misunderstandings can lead to delays, rework, or even failed boards.
Don’t forget to:
Clearly state performance and environmental requirements.
Define your delivery timeline.
Share how and where the product will be used.
Include any testing needs like ICT, FCT, AOI, or X-ray.
Clear instructions help your electronics contract manufacturer meet your quality and timing goals.
6. Rushing to Select a Electronics Contract Manufacturer (ECM)
Not all manufacturers are the same. Choosing the wrong partner can hurt your project’s quality, cost, and delivery.
Mistakes Includes:
Selecting a manufacturer based only on price.
Ignoring essential certifications, past experiences, or manufacturing capabilities.
Poor communication during early conversations.
A good ECM helps you avoid common PCB assembly ordering mistakes and becomes a long-term partner for your business.
You May also Read: How to Choose the Right Electronics Contract Manufacturing Service Provider
7. Skipping Proper Testing and Inspection
Testing is key to ensuring your board works as intended. Many OEMs assume the manufacturer will handle it, but that’s not always true.
Mistakes include:
Not requesting in-circuit testing (ICT).
Skipping functional testing (FCT).
Not including X-ray or AOI for complex or dense boards.
Assuming the ECM will choose the right test procedures.
Build testing into your planning process to avoid product failures later on.
8. Poor Communication With Your Assembly Provider
Most problems during a PCB assembly order come from unclear or inconsistent communication.
Here’s what to fix:
Assign a single point of contact for the project.
Respond quickly to questions or file clarifications.
Keep your manufacturer informed of design changes or schedule updates.
Don’t make assumptions always confirm technical details.
Always reviewing queries or engineering feedback
Clear communication reduces errors and helps your PCB assembly provider deliver better results.
Final Tips to Avoid PCB Assembly Mistakes
Here are some quick takeaways to keep your next project on track:
Do a full review of your Gerber files with your ECM before sending them.
Keep your BOM complete, with second-source options where possible.
Plan testing and inspection from the start.
Get a detailed PCB assembly quote that includes materials, testing, and delivery.
Set up a strong communication plan with your manufacturing team.
You May Also Read: How to Choose a Reliable PCB Assembly Company for Your OEM Project?
Conclusion
Avoiding these 8 common PCB assembly ordering mistakes can make a big difference. You’ll save time, reduce costs, and improve product quality.
At A2Z Electronics LLC, we work with OEMs to simplify the PCB assembly process and deliver reliable results. From assembly to sourcing and final testing, we’ve got your back.
Do you need support for your next PCB assembly order? Contact our team for a fast quote and expert assistance.
FAQs
What are the most critical files needed for PCB assembly?
You’ll need Gerber files, a complete BOM, Pick-and-Place (centroid) files, assembly drawings, and fabrication notes. These files must be accurate and version-controlled to avoid delays or errors during production.
Why is DFM important before ordering?
A DFM (Design for Manufacturing) review helps identify layout or design issues that could cause problems during assembly. It reduces rework, saves time, and ensures your design is ready for production.
How do I choose the right PCB material?
The right material depends on your product’s application. FR4 is standard, aluminum is better for heat dissipation, and high-TG materials are ideal for high-temperature or high-frequency environments.
What types of testing should I include?
Include in-circuit testing (ICT) and functional testing (FCT) to ensure quality. For complex boards, add AOI and X-ray inspection to catch hidden or hard-to-see defects.
How do I ensure effective communication with my ECM?
Keep communication simple and clear. Assign one contact person, respond quickly to questions, confirm all changes, and regularly check in with your ECM throughout the process.
