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.
I agree, often it is hard to truly pinpoint the problem before actually getting it fixed. Some youtubers show more of the thought progress, but on the other hand that tends to make videos long and in my opinion a bit boring.
Depends on the presenter and topic a bit – I’ll usually get very bored very quickly of a ‘tuber going through the thinking process and evolution of that process when I am already several years ahead of them on this topic no matter how great the presentation… Even This Old Tony could manage to be a bit boring from time to time, and despite the handicap of being just a pair disembodied hands and workboots man is there ever panache in the presentation…
But if its something I’d never considered in this way, or am not very expert on even a bad presenter might remain engaging enough and going through the thought processes is then useful – lets me learn from their mistakes, consider the problem from a new POV – sometimes get to feel superior because even though its not my area I’ve predicted the pitfall, or stupid when I’ve so far missed the gotcha they then talk you through etc. And sometimes the progress made is satisfying to watch in its own right.
Sadly, this is the state of youtube. And people have a right to call BS and be upset about it. I agree with Jim.
All down to how it is done – when it is done in the way I read it as in this case it is just the same as saying ‘same time next week?’ – It is in context the same thing really, except if you don’t subscribe you might not learn about the next tea break meeting and never find out as yt undoubtadly won’t feed you the next video when you want it to. But watch but stupid video you hated because your friends suggested it and you’ll get bombarded by more of that crap for weeks before yt catches on…
When you are clearly doing it deliberately because the almighty algorithm demands you break up a project to do it again and again every week/few days to build engagement and get more view counters it is annoying BS. But when you have put out a decent length technical video, even detailing the failures you should have known better than to make and have reached a natural break point with the last prototype meaning a trip back to the drawing board is required…
I guess what really frustrated me was that he had already accomplished all that I would need, but didn’t go into much detail at all about how his proof of concept model worked. And somehow it went from 90 seconds per via (fine by me) to 10 minutes, which isn’t going to work for pretty much anybody. It’s like an advanced form of feature creep, where before you even get started you set the goals to “does everything automatically, quickly, and cheaply”, and as a result ignore the perfectly good outcome you had at step 1. It’s like if the Wright brothers envisioned a jet fighter, and got disappointed because their flyer was so slow.
It depends on PCB size and complexity, but – PCB rivets are a thing.
You can even get hollow ones, for mounting through hole components.
I used that approach as well and it quite fast. Maybe the best would be to have a drill+rivet placer for a one step-process but gettint the rivets into the holes would get difficult – might help to use neelde-magazine for the rivets but then the task of filling the magazine is pain again. ;D
If you’re mounting through-hole components in the hole, you don’t need the rivet…
why not just get a suitable plastic tub and automate the chemical baths? that seems fine for a DIY system. this seems needlessly complicated to do it one at a time
Soldering through hole components on both sides worked well forever, or a thin wire.
Yep – and when making the board, try to land two vias near eachother. Then you can solder them together using one loop of wire bent into a U shape to it holds it’self in when you solder both sides.
I’ve never made a PBC, so I’m sure I’m just missing something. But I won’t learn unless I ask, so…
Why does the via need to be electroplated? Why not drill a hole, insert a very thin wire (28 AWG?), fold it over slightly on both sides and apply solder? Or alternatively, a crimp / cold weld? (Not sure if a crimp is possible without cracking the board.)
With a simple two sided board the answer is technically it doesn’t, you could insert a rivet, component or wire and solder to bridge across the planes no trouble. But via do help solder flow into the hole so those through hole parts really stick, and the through plating helps stitch the copper pads on either side together so it can handle a bit more rough treatment while you are soldering, and they can be dramatically smaller footprint to just bridge the sides. Also becomes rather important if you are going to end up laminating even more layers that the connections between them stay inside the surfaces.
The big gain to a system like this would simply be the manual labour saving – if you have a complex circuit and can only easily make 2 layer boards (which is likely the case for home gamers) you probably have lots of via to jump traces over each other, and that means lots and lots of extra soldering.
This is what many of us HAVE done, when we need something quicker than the turnaround time for the popular board fabs. And it’s faster than even 90 seconds/via! But it won’t work for any design with 4 or more layers, including pretty much anything with ball grid array devices.
I wonder if pop rivets might work as vias :)
Back before multilayer boards, most 2-sided boards didn’t even have plated through-holes. There were “PCB Repair Kits” that included brass rivets that could be used to hold down pads that had been lifted when desoldering a component. Not quite pop rivets, but more like a much smaller version of eyelets that an be crimped onto fabric. I don’t think I’ve ever seen pop rivets in a small enough diameter to be used on most through-holes, and these would still be limited to 2-sided boards because there’s no way to ensure contact to inner layer circuits.