You’ve spent the time in engineering and your PCB design is ready for its first prototype build. Congratulations. You are now ready for the next step of having the hardware built, but first, you need to select a contract manufacturer to do the job. There is a lot to consider here, and different CMs will present you with different price scenarios to choose from. So how do you choose? What should be the criteria for selection?
Building a PCBA prototype will involve a lot of different processes and costs all combined together. The CM you choose will use a PCB fabricator, which will have a cost attached to it. The parts used by the CM will also affect the cost, depending on which part vendors the CM works with. The processes the CM uses for manufacturing and test will also play a big role. The key is to understand everything that goes into building your prototype and the prototype PCB assembly costs associated with that so you can make a decision about the best CM to partner with.
Why Prototype PCB Assembly Costs Are Higher Than Production Builds
The first thing to know when it comes to understanding prototype PCB assembly costs is that prototype builds will typically cost more than production builds. There are many reasons for that. Here are a few of the differences that will increase the cost of a prototype build:
- Documentation: The amount and quality of the documentation that accompanies a prototype build may not be complete, and the manufacturer has to update or create the necessary documents to proceed with the build.
- Component research: The parts in the design may not be the best choices due to lack of availability, or being not recommended for use or end of life (EOL). As a result, the component engineers will need to spend time researching suitable replacements.
- Engineering: The design may be more conceptual than production-ready and require more engineering analysis to make sure that potential manufacturing errors have been corrected.
- Design for X: For a prototype, there often are more design for assembly, design for test, and design for debugging concepts that should be included. DFA and DFT enhancements will help when the board transitions to production, while design for debugging is essential in a prototype. Options such as test probe points and component sockets should be added to make exploring the performance of the prototype or investigating alternative design strategies easier. This is a much more cost-effective solution than trying to add costly hardware modifications later on for debugging purposes.
- Time to market: To get your prototype built as quickly as possible, the CM will fast-track the project through the factory. Although the manufacturing steps such as placing and soldering components will be the same as a regular production board, a prototype will be built in smaller numbers with dedicated team members to guide its progress.
- Quantity: Quantity is a major driver on cost. The economic build quantity considers optimizing PCB panel size.
To summarize, building a prototype PCB assembly will require extra effort outside of the normal PCB manufacturing processes. This will usually result in higher assembly costs if you are using the best CMs for the job.
Why Lowest Price Isn’t Always Best for Prototype Assembly
Knowing the processes and facets involved in your prototype assembly, the first criteria that you should consider when choosing a CM is what level of contract manufacturing is needed for your project. There are different levels of CMs for building printed circuit boards, and they will have different capabilities and approaches to doing prototype work.
The lowest level of contract manufacturer is the “garage shop” CM. They will have the ability to do quick work for a low price, but they probably won’t have all of the infrastructure in place to fully support your prototype. They may lack engineering capabilities to prepare your prototype design for manufacturing or the ability to work with you on component selection.
On the other end of the spectrum are the “mega” CMs. These shops have all of the resources that you would expect for complete engineering and manufacturing support. Unfortunately, their business model is set up for high-volume production runs, and smaller prototype builds can get lost in the shuffle or lack the personal support that you may need.
Finding a low-volume, high-quality CM that is between these two extremes may not be the least expensive, but it will give you the best value for what you pay for when it comes to building a prototype PCB. Making the wrong choice in a CM can end up costing you more than you might have saved by going with a less expensive choice. Consider the following:
- Some CMs may not provide you with a full documentation package that contains all of the modifications they made during production. This means that you will have to spend time and money recreating their work to get the next round of boards reliably duplicated.
- Similarly, some CMs won’t identify and review with you manufacturability issues and areas for improvement to optimize the assembly process. This may result in a less expensive build, but you will end up paying for it later when dealing with unexpected design changes that the CM performed without notifying you.
- Engineering analysis of potential design or manufacturing issues, bill of materials (BOM) scrubbing and validation, and adhering to quality manufacturing standards may be substandard, or not done at all. By not putting time and resources into these practices, it could end up costing you later to find and correct engineering and manufacturing problems that should never have happened.
- Some CMs may not have a vast network of vendors to use for the fabrication of the bare printed circuit board, or components that they will use for assembly. This could cost you more in time, performance, and expense.
Choosing the right CM is obviously extremely important to the success of your prototype project. Although it may cost you more for the prototype build, you will be getting a much better value for your money.
What You Should Expect From Your CM for Your Money
As we’ve seen, getting a prototype PCBA built will cost more than a regular production board. In addition to added expenses due to the nature of manufacturing a prototype, you should know that CMs that are best suited for the job will cost more as well. In return, you should then expect a higher level of quality from your CM for your investment, particularly in the following areas:
- Experience: Your CM should have a wealth of experience in building prototypes for multiple market segments, and they should hold industry standard certifications for manufacturing. In addition to building your prototype, they should also be able to work together with you so that your prototype can be easily converted into a high-volume production PCBA.
- Resources: Your CM should have good business relationships with multiple vendors for components, materials, and bare-board fabrication. They should be able to respond quickly to the needs of your prototype from their network of business partners.
- Facilities: Your CM should have an up-to-date facility equipped with the latest technology and processes that are well-documented for manufacturing your prototype.
- Personnel: Your CM should have personnel that is highly trained in manufacturing and testing PCBAs. They should also have an experienced engineering team that will serve as an extension of your own engineering staff without the extra overhead to support. In addition, many quality CMs will have a dedicated NPI specialist on staff who is responsible for understanding the customer’s requirements and building an internal process to achieve success for that process, which ultimately results in creating a transferable package for the production team.
At VSE, we have the experience, resources, facilities, and personnel that you need for the production of your prototype PCBA. In our state-of-the-art manufacturing facility, we make sure that all of the details surrounding a prototype build are taken care of—from the initial engineering analysis and component research through manufacturing and testing. Through it all, we work with you to make sure you end up with a complete documentation package and a prototype build that is ready for mass production, so you don’t waste any time or expense going to the next phase of your product development.
