Until recently I believed that having PCBs assembled by a professional service is either too costly for small batches or not possible at all. That was until I realized that some PCB manufacturers offer an additional assembly service (PCBA) and that their minimum order quantity (MOQ) is often very low. But which service should you use for future prototypes and market tests?
So I decided to pick a handful of PCBA services and order the same small board from them. Placing the same order with different services should allow me to compare quality, speed and costs between the different services.
In this post, I’m going to compare four assembly services for printed circuit boards. I got quotes from four services but placed orders with only three of them. One service (Seeedstudio) was simply too expensive for my little experiment.
All four services have a combined PCB/PCBA service. The services first manufacture the printed circuit boards and then they use the boards in a second stage to solder the components. Before you place the order you have to define the job with a couple of form fields. The required documents vary slightly from service to service but basically, you have to deliver Gerber files for the PCB stage and a detailed bill of material (BOM) in CSV or Excel format.
Two services also required a file which describes how to position the components with a pick-and-place machine, sometimes referred to as centroid files. CAD tools often can export this information. Eagle CAD, for instance, can do this with a few simple steps.
In the following paragraphs, I will describe the four services. At the end of this post, I will compare them side by side.
PCBWay offers a rich set of services: regular PCB manufacturing, SMD stencils, flexible PCBs, advanced PCBs as well ass PCB assembly.
For the initial price quote, you have to provide 4 numbers: quantity of boards for assembly, number of unique parts on one board, number of surface-mounted parts and number of through-hole parts.
You can then choose from three options how the components will be sourced: either PCBWay sources the parts for you or you send the parts to them. Or you provide some of them and PCBWay sources the rest.
For the initial quote, you also need to provide the size of the PCB and a couple of other aspects for PCB manufacturing. To get the final quote you need to have the Gerber files, a bill of materials (BOM) and a CSV file containing coordinates for the pick-and-place machine. The BOM is in Excel format. It’s best to download their Excel template and to provide the required information.
It took only a couple of hours until I got a reply from a PCBWay sales rep. The email contained an updated Excel file with costs per part. The sales rep asked me to check the BOM to make sure that they will source the correct components.
Since everything seemed to be as planned I paid. PCBWay has a wide range of payment options: PayPal, Credit Cards, Western Union and even Bank Transfer.
What I really liked about the PCBWay platform was the possibility to closely track the progress of the PCB order. The assembly doesn’t quite provide this level of information. I would assume that the IT system for PCB production is a lot more mature and integrated than the one for assembly. For my small quantity they probably even soldered by hand.
14 days after I placed the order I received an email with photos from some PCBs. I told them that they were not mine and they quickly fixed the mistake by sending photos of my order. With the photos you can verify that the first assembly is according to your plan before they continue with the rest.
A day later the PCBs were shipped by DHL to Switzerland. Another 3 days later the PCBs were in my inbox.
Note: for this order with PCBWay I had used a slightly different design than with the later providers. In this design, I had used the wrong coil and they were not able to fit the board. So, in the end, I wasn’t able to test the functionality of the board. However, this was my mistake, not PCBWay’s and I believe for this comparison this is irrelevant. For full disclosure, I thought you should know.
LocoPCB is another manufacturer who also offers assembly services. Initially, I thought “Loco” stands for “low cost” but a closer look at their logo reveals a locomotive. So it’s relatively safe to assume that “loco” is short for locomotive.
Besides fun facts about their name, the ordering process for PCB and PCBA is very similar to PCBWay. They offer many options for the PCB manufacturing and for the assembly you can choose to provide parts by yourself, have them source the parts for you or a mix between the two. Minimal order quantity is 5 boards for both PCB manufacturing and PCB assembly. While in my first order I could profit from a discount for the assembly base fee the regular price is USD $50.
To get a quote you need to upload a ZIP file with the Gerber files. For PCB assembly an additional Excel file following their template has to be provided. The BOM has to contain the designator (e.g. C1, C2, etc.), a serial number of the part manufacturer, a column for quantities and additional description. You can use the description field to give them additional instructions per part. For instance, I wanted them to source the male header pins, but they should solder them. I wanted them to add the pins in the anti-static bag so the user could later decide if he needed the pins or not.
I placed the order in the evening (Central European Time) and the next morning I already had a response. They suggested replacements for some of the components in the BOM since they were easier to source.
All in all, they were very responsive during the order process. I had the feeling that their engineers were actually looking at the PCB design to make sure that the order would be completed as fast as possible in good quality.
Production and shipment were the fastest of the three tested services. Only 14 days after placing the order I had 10 perfectly looking boards in my mailbox. Quality was perfect and they worked as expected.
LocoPCB made to me the impression of a younger company than PCBWay but maybe I should explain this. On one hand, the LocoPCB IT systems are not as far integrated into the production process as PCBWays. While I could track every step of the production process with PCBWay the information available to me in LocoPCBs user interface was much more sparse. On the other hand, LocoPCB also seems younger because they were more eager to support me personally during the ordering process. This in my experience is usually the case for smaller and younger companies.
PCPBGogo was the third service from where I ordered the Buck/Boost converter board. The required information to get a quote is nearly identical with the other two services. By filling out the number of boards, number of unique parts, number of SMD parts and number of through-hole parts you get a preliminary quote. For a full quote, you also need to upload Gerber files as well as a BOM-Excel in their format.
Parts can either be sourced by PCBGogo, by you or as a mix. Minimal order quantity is 5 boards. The user interface looks rather old and the email communication was not as personal as with the first two services.
After completing the first board they also sent me a photo for review:
PCBGogo was not only more expensive than PCBWay and LocoPCB but also much slower. It took 27 days from placing the order until the 10 boards were in my mailbox. So it took nearly twice as much time as with the fastest contender (LocoPCB).
If you are an electronics enthusiast like me you probably know Seeedstudio already. They have a shop with many cool gadgets to build fantastic projects. But did you know that they also offer a lot of other services? This includes PCB/PCBA, 3D printing, and kitting services. So being quite a fan of all that Seeedstudio does I wanted to include them in my little experiment.
Their PCB/PCBA order forms look suspiciously similar to the ones from LocoPCB and PCBWay and I wonder Seeedstudio actually sub-contracts one of the other two services to manufacture the PCBs. Even the BOM has exactly the same format as LocoPCBs. After placing the request-for-quote they didn’t respond for a long time. After asking them if they had forgotten my request they answered that they couldn’t source the component described as “Any 2.54mm pin header”.
Finally, I got a quote for USD $170, more than twice the price compared to the cheapest and fastest provider. So I decided to ditch Seeedstudio from my experiment, just far too expensive!
The following table compares the four services side by side:
|Parts supplied by service||Yes||Yes||Yes||Yes|
|Parts supplied by customer||Yes||Yes||Yes||Yes|
|Min. Order Quantity||5||5||5||5|
|Files Required||Gerber, Pick&Place, BOM||Gerber, BOM||Gerber, BOM||Gerber, BOM|
|Assembly Costs||$30||$30 (Regular $50)||66||N/A|
As you can see from the table the costs are distributed in different ways. PCBGogo, for instance, has reasonable component costs but exorbitant shipping costs. For exactly the same shipping service (DHL) as the other two contenders. LocoPCB has relatively high component costs but won the price category because of the one-time assembly-base fee discount. Without that LocoPCB would be level with PCBWay. PCBWay offered a good quote for the components but a relatively high price for the 10 PCBs.
My personal recommendation currently is to go with either PCBWay or LocoPCB. I ordered a third revision of the High Efficiency Buck/Boost Converter Board from LocoPCB and had it delivered directly to the ThingPulse warehouse in Shenzhen, which worked perfectly. You can order the board from our shop how: Buck/Boost Converter Board