How to assemble your PCBAs

If you’re looking for a solution to populate PCBs for your product or prototype, you’ve got a lot of options. Each one has a different optimization between time and cost that can be beneficial depending on what’s important to you. In this post, we’ll outline the common methods of getting your PCBs populated, and what the benefits are of each.

Hand Population

Hand population is the simplest, cheapest, and most straightforward method of stuffing your boards. Provided you’re doing the population yourself, or you have a pre-trained technician to perform the task, there are no setup costs. It can begin immediately with nothing but a stencil, some paste, and a pair of tweezers.

However, production is inherently slow and does not scale well. It can be expensive when considering the hourly wage of the technician. This method can also be prone to error. When hand-placing thousands of small SMT components, the likelihood of placing a diode backwards or putting a resistor in the wrong footprint is almost certain.

In general, hand population is a fantastic method for a short run of boards where the final product is given thorough scrutiny, but becomes more difficult as you scale up production.

Outsourcing

On the other end of the spectrum, outsourcing your PCBA assembly is the least manual method. All job setup, pasting, and assembly is done for you at a different facility. After you place your order, you receive finished boards in the mail. There’s quite a bit of up front communication and setup with your vendor to prepare them for production, but once you’re up and running it’s pretty smooth to keep it running.

There are a few downsides to this method. First is the associated cost. Although this method is convenient, it charges a premium on the service, which can be brutal for a product’s profit margin. Also, these services usually have a minimum order quantity, so you need to invest a lot of money up front to even be able to place an order.

Second is time. Depending on the service, you might have to wait many weeks before the boards arrive. If you need prototypes built quickly or on-demand, this can be a non-starter. Some services will deliver boards more quickly, but charge a premium for that benefit.

Third is quality. Although many assembly shops will perform visual inspection, they might not be checking the functionality and performance of the boards before shipping. This greatly increases the chance that an error like a backwards diode makes its way into every board in a production run, only to be discovered after they've all been built and shipped.

Outsourcing is a great method for getting boards made if you’re at a large scale of production, have a large profit margin, and aren’t changing your designs often.

In-House

At the best of both worlds is automated in-house production. Using a pick and place machine like the LumenPnP, you can assemble serious quantities of boards with a fast turnaround and low unit cost. This method allows for fast, accurate placement while also being able to perform your own quality checks before committing to a huge production run.

Using the LumenPnP to assemble boards in-house means you can get PCBAs produced as soon as you need them, with minimal human intervention. After setting up your job, board population is fully automatic and computer controlled, greatly reducing the risk of an incorrectly placed part. 

In-house assembly is considerably less expensive than both outsourcing or hand assembly. When hiring a company to assemble your PCBAs, you're paying a premium for their service, greatly reducing your profit per unit. Hand assembly takes a tremendous amount of time, and the cost to hire an assembly tech to perform the task adds up quickly. In-house assembly with a desktop pick and place like the LumenPnP is the best of both worlds, saving money by removing the middleman, and saving time by automating the process.

This method also allows you to make a serious production quantity of boards. Whether you're making a small batch for an internal prototype run, or fabricating your product for customers, in-house production with the LumenPnP can handle the throughput.

Want to see how much money and time the LumenPnP can save you? Check your board with our web tool to find out.