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The development cycle of the company I work include building alfa prototypes, sometimes in breadboards, and beta prototypes in printed circuit board assembly.

A considerable slice of the development time is wasted waiting for PCBs prototypes to be builted by PCB manufacturer here in Brazil. Since the time spent is a lot, I'm thinking in ways to somehow speed up the production of these prototypes in my company.

Do you have any suggestions or experience that you'd like to share on this particular subject? Maybe some cost affordable machine DIY to build PCBs at home?

RHaguiuda
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  • Are you talking fine-pitch surface mounts? Also, are you talking about printing the PCBs, actually populating them, or both? – Scott Seidman Feb 25 '14 at 14:33
  • You don't have *anything* else to do while waiting for boards and parts to show up for one board? I usually send the board out for fab, then do the BOM, then get parts ordered, which then all show up together about 2 weeks from sending the board out. Meanwhile you can start on the firmware, comm spec, host software, or even work on a completely different project. – Olin Lathrop Feb 25 '14 at 14:37
  • If money isn't that much of a concern for the prototype boards, a lot of PCB manufacturers offer express production. This often means >200% production cost but its not uncommon that you can get the PCBs within 3 days. We use this if we have very tight schedule or for the second prototype run where only small corrections were made and everything else is more or less done. – Rev Feb 25 '14 at 14:40
  • I've heard of *multilayer* boards shipped within 16 hours, but the price was astronomical. I prefer to *plan* things so that 1-2 week delivery is not a problem. – Spehro Pefhany Feb 25 '14 at 14:43

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For fairly simple design and medium trace width you can either draw the traces on the raw PCB board with an etch-resistant paint and etch the rest of the cooper out by some chemicals, such as Iron Chloride (FeCl3) or Cooper Sulfate (CuSO4). For better quality you can print the layout of the traces on a transparency and use the photo-developing process to develop the design before etching.

For example, here is a nice Makezine article about how to make DIY PCBs http://makezine.com/projects/cheap-friendly-and-precise-pcb-etching/

However, for designs with multiple layers, tiny SMD components, BGAs, High speed digital signals, with silk screen and solder masks, and traces under 10mils you'ļl be better off ordering a PCB from one of many PCB fab houses. Some offer expedited services - PCB in a couple days, if you can afford the cost and shipping.

elomage
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  • In my opinion the problem with the self-made approach VS express order is, that it tends to consume more time that one may initially think, and in the end you don't even have the "final thing" in your hands. If one person spends about one extra day, thats easily >100$. For that you can already get a three day express order for a small PCB and you don't have to mess with some in between solution. – Rev Feb 25 '14 at 14:57
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    @Rev1.0 (good user name) is right, in my opinion. Unless your final article is the homemade board, you're going to have to make many compromises in design rules to get the prototype. It's now not that hard to get quickly made prototypes with 2, 4, 6, 8 layers, routed outlines, fine pitch, gold plate etc. at a reasonable price. Things that would be prohibitively expensive or time consuming to do yourself. – Spehro Pefhany Feb 25 '14 at 21:03
  • I agree that a professionally fabricated board would be better and even more cost effective w.r.t. the time spent making the one yourself. However, if you take in account the geographic location, local market, hourly salaries, and context, your economy may change. For example, my students have made a simple H-bridge boards in less than a day, and I don't blame them for not ordering the PCB from a Fab house. – elomage Feb 26 '14 at 20:46