PCB artwork has been around nearly as long as PCBs have been manufactured. Engineers love adding a personal touch to their work, and they love finding new ways to push available manufacturing processes to unique and interesting results. Sadly, aesthetics are often seen as an after-thought, and so there are rarely significant advances in the processes specifically devoted to those aesthetics. Traditional manufacturing processes provided a simple 4-color "palette" to work from (possibly 1 or 2 more if you got really creative), and that was that. Even still, limitations lead to creative solutions, and there's a lot of really great examples of PCB artwork out there.
For a long time, unique soldermask colors were one of the main ways to stand out from the crowd. A few years back, OSHPark introduced a truly unique stackup with a solid black core and clear soldermask, which highlighted the masked copper traces in a really cool way.
But people wanted more.
In recent years, there have been a lot of really cool examples of uses for PCB manufacturing that push beyond typical circuit board designs. Because of how cheap they have become, combined with the high precision processes, PCBs have started seeing uses for things like cover panels, or even complete device enclosures, things that might have previously been made from sheet metal. Being able to combine structural and aesthetic elements, and even include electronic aspects such as reverse-mount LEDs for panel back-lighting, has opened a lot of new doors for product designs.
With those new ideas comes a new push for innovation in the process capabilities to produce them. One of those new process innovations is the introduction of full-color UV ink printing. While this is not remotely a new technology in and of itself, its use in PCB manufacturing is. The first time I remember hearing about full color PCB printing was back in 2023, and I couldn't wait to try it out. Sadly, that early announcement came out WELL before the service was actually available, and I eventually forgot all about it, until I was approached a few months ago by PCBWay, who offered to sponsor a project of mine.[1] I've been working on a no-cut, no-solder BlueRetro kit for the SNES for about a year now, and I figured it would be a perfect fit for this.
One of the most frustrating parts of the workflow for full-color PCB printing right now is the lack of standardization. Every other layer on the PCB is defined by industry-standard gerber files (or excellon for drills), but no such standard exists for full-color images. It seems simple enough, you just send them an image file, right? Not quite. In addition to the actual image itself, you need a way to specify the exact scaling and alignment so the image actually goes where you want it to. And that's where the fun begins. Some manufacturers opt for custom in-house tools built into their online order form workflow, sometimes relying on proprietary file formats or other weird caveats. These can be cumbersome and annoying, but they seem to work well enough. PCBWay has opted for a different approach. They accept completely normal .png (or even .jpg) image files, and instead rely on the use of reference images or other communication at order time to produce the correct scaling and alignment. This is a bit different to other low-cost prototyping fabs where their upload process is more automated, and you usually only end up communicating with a real person if something goes wrong along the way. As someone who usually prefers the more automated approach, this took some getting used to, but I've found that in situations like this, where you are trying to accomplish something more specialized, speaking to an engineer early on in the process really makes the whole thing a lot smoother.
That being said, the process of getting full-color PCB's made was different enough from the normal PCB ordering process that I found myself feeling a bit lost at first. It reminded me a bit of my first time ordering PCB's from one of these online manufacturer and seeing what felt like an overwhelming number of options on the order form and not having any idea where to start. I remember wishing somebody would have explained how to navigate all of those options to a newbie like me, and a few years later, Dave Jones of EEVBlog came out with this video that did exactly that. I highly recommend watching the whole thing if you find yourself in that position (yes, it's a long watch, but it's worth it). I wasn't able to find any similar guide to ordering full-color printing, which makes sense since it's so new and also due to the lack of standardization that I already mentioned, so let me go through the process here. This was my first time, so there might be better alternatives to some of the steps here, let me know in the comments if you have any ideas.
You're going to want two things to start drawing your artwork. First, you're going to need a reference image of the PCB, and second you're going to want an outline of the board. In KiCAD, I chose to use the nicely rendered board from the 3D Viewer for my base reference. There's a bit of parallax, but my board was small enough it didn't make much difference. You'll want to turn off any 3D modeled parts so they don't obscure the surface of the board that you're going to be decorating, you can turn them off in the Appearance panel. Be sure you have the camera properly centered and aligned, not slightly rotated. Use the Flip Board button (or just press F) to flip the board for the back side. File>Export Current View as PNG to save the image. To get the board outline, from the PCB editor, File>Plot, uncheck all layers except for Edge.Cuts, and set your Plot format to SVG.
Once you have completed your design, you'll want to export two versions of the final image. First, you'll want to export the final reference image with all layers, showing the board as you want it to appear. Second, hide the board reference layer and just export the actual graphics that you want printed. Be sure that this image includes an alpha/transparency channel (i.e. export as .png, not .jpg). Another thing that PCBWay isn't clear on is whether or not to include the outline in this file, I chose to do so, and then requested that they remove the outline in the final print.
Once you have your images exported, bundle them up with your gerber files, upload to PCBWay, and select the option for UV Printing Multi-Color based on which side(s) of the board you want them to print on, and if you have any additional details you thing might be helpful, you can leave them as a note in the "special request" box toward the bottom of the page.
Overall, I was pretty happy with the process. I hope that if this catches on in popularity, maybe KiCAD will add support for importing full-color image files directly within the PCB editor in order to handle the alignment, scaling, exporting, and rendering all directly rather than having to Photoshop together the reference layers, but until that happens, this is still a fairly straightforward process. And the results really speak for themselves. I definitely look forward to exploring this option more in the future, and I can't wait to see what other people are able to come up with as well. Now, I just need to finish this project up so people can actually buy them...
[1] Sponsorship disclosure: PCBWay provided the PCBs featured in this post for free, but I was not paid. All opinions are my own. My full sponsorship guidelines are posted here
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