Shoe shopping for backpacking trips is a semi-illuminating experience. While there was much discussion of the pros and cons of different features like style, ankle support, etc., a common pain point was the discrepancy in half sizes. Due to the consistent walking while bearing additional weight, backpackers’ feet tend to swell slightly during the day. Thus a marginally larger shoe accommodates this increase without becoming overly cumbersome.
PCBs also need some wiggle room at the outset of manufacturing. Development teams should seek a contract manager (CM) that is compatible with production forecasts, whether that’s small-scale prototyping, an intermediate level of product rollout, or mass production of an established design. Another key consideration will be the services offered by the CM, with a greater range of services typically offered at higher-capacity facilities. The key to choosing a CM to partner with for prototyping or low-volume PCB manufacturing is to find middle-ground that balances services against cost and turnaround time.
The Garage Shop CM
The lowest tier in the hierarchy of CMs is geared toward smaller operations; they are sometimes informally referred to as garage shop CMs. These smaller CMs are positioned well to quickly produce prototypes and low-volume PCB runs due to an adherance to lean manufacturing, or the focus on waste and turnaround time reduction. As their production schedules are less concrete, they also have the advantage of flexibility in adapting designs. As these size of shops lack the bulk purchasing power of larger manufacturers, they may struggle to provide stability and the resources of a major CM.
Consider these issues with a lower-tier CM:
- Fewer resources to validate your design and documentation before assembly.
- Fewer quality controls are in place to ensure your boards are manufactured to the highest standards in design rules.
- They may not be able to optimize your build for speed or cost.
- Unlikely to have the advanced engineering capability to identify even marginal design or assembly issues pre-production, let alone resolve the issues.
- Probably can’t provide a bill of materials analysis or have component vendor relationships they can leverage during part shortages [link to Parts Shortage blog post] or other procurement problems.
- Lack the documentation and other capabilities that allow for customers to transition to large-volume manufacturing.
- Less than adequate testing and development capabilities.
The Mega CMs
On the other side of the CM spectrum are the larger operations. These upper-tier CMs are usually the mega-manufacturers that are often located overseas and are known for building massive amounts of PCBAs for smartphones and other personal electronics. The biggest advantage to working with these CMs is that they have the resources, staff, quality controls, and external relationships that many smaller shops often don’t have access to.
On the other hand, there are also some major disadvantages when working with a mega-CM:
- Their processes will likely be rigid, inflexible, and geared only toward high-volume, high-spend customers.
- They usually have massive lead times due to all of their work.
- There are often multiple levels of bureaucracy for the customer, which can slow communication and contribute to a lack of personal relationships.
- Differing time zones between you and the CM can also hinder communication and delay the production of your PCBAs, especially if design or assembly issues need to be addressed.
The Right CM for Your PCB Assembly Low-Volume Builds
Just as the SUV was so successful at striking the right blend between the extremes of small and large trucks, so will a good mid-level CM be for providing low-volume runs of your boards. Like a smaller garage shop, a mid-level CM can be flexible and responsive to your requests without the rigid bureaucracy of the larger CMs. They will be able to offer you top-level CM services, such as full engineering capability as well as state-of-the-art facilities and processes without the time-consuming and costly overhead of a mega-company.
When choosing a mid-level CM for low-volume PCBAs, look for the following:
- Full electrical and mechanical engineering capability to assist you in resolving any manufacturing and component design issues, including identifying alternate parts if your initial parts aren’t available.
- Facilities and processes that adhere to the strictest industry standards.
- Prompt, personalized service that cuts through the red tape to deliver on time.
- The flexibility and capability to support unusual product requirements or unique processes.
- The ability to provide design documentation to transition to high-volume production.
- Design for excellence analysis and the ability to implement solutions to enhance your product’s manufacturability and performance.
At VSE, we know what you need for your PCB assembly low-volume runs, and we have built a thriving business taking care of customers who have needs similar to yours. We have all the sophistication and benefits of a top-level CM but the flexibility of a low-volume shop to give you a quicker turn. We can complete full production runs to meet the needs of our clients, but we specialize in low-volume, high-mix manufacturing. Whether you need a thousand pieces or just one, we can expertly build your PCB.
