Although DIY PCB making has made great strides since the early days of chemical etching, there’s one fly in the ointment: vias. These connect individual layers of the board with a conductive tube, and are essential for dual-layer PCBs, never mind boards with a larger layer stack. The industry standard way of producing them is rather cumbersome and doesn’t scale well to a hobby or prototyping context. Might there be a better way? This is the question that [Levi Janssen] set out to answer with a new home PCB manufacturing project.
The goal here is to still electroplate the vias as with the commercial solution, just without having to use chemical baths. This way it should be suitable for an automated setup, with a tool head that performs the coating of the via with a high-resistance conductive ink before the electroplating step, all without submerging the entire PCB. After an initial experiment showed promising results, [Levi] committed to a full prototype.
This turned out to be a bridge too far, so the prototype was scaled down to a simpler machine. This is where the main issue with electroplating one via at a time became clear, as a standard 0.3 mm via takes easily 10 minutes to electroplate, even with an increase in voltage. At that point ordering a PCB from China becomes the faster option if you have enough vias in the design. Fortunately [Levi] figures he may have some solutions there, so we’ll have to wait and see what those are in the next installment. The video is below the break.
It is unfortunate that [Levi Janssen] did not give details about why his prototype did not meet the performance of his proof of concept test. For my own use, I wouldn’t mind a less automatic solution, where a hand-held unit that clamps onto a PCB is used to first coat the via holes with the conductive paint, where I would move the unit manually and coat all of the vias, then a separate plating unit would be used to plate all of the vias. This means that any drying time required for the conductive ink wouldn’t be a factor. There could be separate plating heads for different sized plated holes. Since I use surface mount components almost exclusively aside from connectors that are only available in through-hole, I tend not to need all that many vias, so his goals of having a fully automated process are less important to me. For me, having to set the plating head in position, clamp it down, turn it on, and wait 90 seconds sounds like a viable (so to speak) solution (so to speak) for prototypes.
BUT, instead of saying what things he thought he could try in future iterations, instead he took the #%%! YouTuber direction of saying “subscribe, and you’ll see.”
While I agree the constant harping on ‘tuber’s need to do in the hopes of appeasing getting interactions to appease the algorithm is annoying I don”t think it really applies very much here as a negative here. This sounds more like a ‘leave it with me, and I’ll run some new ideas past you next week’ that you would get from the folks you chat with at your makerspacer, around the work watercooler, in the pub at lunchtime etc, just in a new context.
My take in this case was he doesn’t or at least didn’t at the time actually know for sure why the more complex ‘automated’ system failed to really live up to expectations. Some alignment issues and the like mentioned but it seems like the act of pumping it through ‘automatically’ rather than doing it by hand had some extra variable or two that need to be found, calibrated or removed so the plating works properly – really you can’t expect anything else but ‘wait and see’ as no doubt there are too many ideas half formed and hard to really articulate.
It depends on PCB size and complexity, but – PCB rivets are a thing.
You can even get hollow ones, for mounting through hole components.