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Common 3D printers (read "cheap") may be used to print masks for PCBs (printed-circuit boards) which use PTH (through-hole) components.

But can they be used to print PCBs which use SMD components? I'd like to make boards at least for Arduino-like SMD chips.

Ronan Paixão
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  • I noticed that your question has a few answers available and has been open for a while, just curious if any of the available answers was able to help. If not, then what questions do you still have? – tbm0115 Jul 03 '16 at 20:17
  • Both answers deal with printing the actual circuits, while the question is about printing masks on common PCBs which would then be corroded. Maybe I need to rephrase my question to make this clearer? – Ronan Paixão Jul 19 '16 at 13:07
  • Yeah, that would help. I don't think you need to reword your question, but maybe just add that note. Also it looks like @TextGeek mentioned masking in a comment that might help. – tbm0115 Jul 19 '16 at 14:38
  • Is there a reason you cannot use photoreactive copper boards and expose them to light with a printed transparency? Desktop laser jet printers can usually print directly onto transparencies to generate photomasks. These can produce quite detailed circuitry but you may need to check the specifics. – TafT Mar 13 '17 at 08:56

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In addition to the thermal issues Tormod raised, there is a conductivity issue. Present conductive filaments are much less conductive than copper. The power loss may be enough to affect functionality. Also, the lost power goes to heat, making the thermal problems worse.

For bulk materials, "volume resistivity" is measured in "Ohm-cm", which is the resistance of a 1 cm cube of the material, measured from one entire face to the opposite entire face (see https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity).

Copper has a volume resistivity of about 1.68 microOhm-cm.

Proto-pasta conductive PLA filament claims 15 ohm-cm (http://www.proto-pasta.com/pages/conductive-pla). Functionalize F-Electic™ claims 0.75 ohm-cm (http://functionalize.com/about/functionalize-f-electric-highly-conductive-filament/).

Printing itself significantly raises resistivity. Proto-pasta claims 30 ohm-cm along X and Y, 115 along Z. More intuitively, each cm of length of a 2.5mm wide printed trace, 0.4mm thick, should add several hundred ohms with the Proto-pasta, or several tens of ohms with the F-electric. That may be enough to matter.

It's probably worth mentioning that there's a specialized PCB printer (the "Voltera") that uses (pricey) conductive ink, and can also dispense solder paste: http://www.computerworld.com/article/2885188/3d-circuit-board-printer-a-smash-hit-on-kickstarter.html

TextGeek
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  • I imagine pre-calculating the resistance of a printed conductor can be a science in itself, meaning it could be difficult to use protopasta for anything complicated! – Tormod Haugene Jan 22 '16 at 22:04
  • @TormodHaugene, that's surely true. I just approximated by cross-sectional area and length, which should be in the ballpark. But layer height, ratio of nozzle to layer height, and many other things surely matter, too. – TextGeek Jan 26 '16 at 14:59
  • Question is about printing masks, not about printing circuits directly. This is a good answer about printing circuits but not about printing masks. -1 – TafT Mar 13 '17 at 08:53
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In theory, I imagine you can, but there are some practical considerations that might need some thought:

If you have a desktop printer with multiple extruders, you could probably print with both one conductive and one structural filament, and thereby build circuits in 3D.

One concern would be the low melting points of most 3D printed filaments, since one would have to limit the heat generated by the mounted components and connections so that the structure of the "board" would not be melted.

Mounting components to the board would also differ from a normal PCB, since you would have to connect the components with the conductive filament without melting the structure of the board. In other words, you probably would have to use conductive filament as "solder", and melt components into place.

Whether you could use typical tools used for mounting SMD components with conductive filament as solder is beyond my knowledge.

Tormod Haugene
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    This is definitely an easy solution with either a multi-extruder and/or updated firmware/slicer that supports mid-print filament stops. – tbm0115 Jan 18 '16 at 15:21
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    I do not intend to print the whole board from scratch with conductive filament, but to print a filament **mask** above a standard PCB. The mask would (if possible) allow corrosion of the PCB copper by standard PCB-making process, leaving the copper tracks where the masks protects them. I'm concerned about if the mask would stick and if it allows fine tracks needed for SMD components. – Ronan Paixão Jan 19 '16 at 15:50
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    Ahh, sorry, hadn't realized that's what you meant. There's a report of someone using NinjaFlex filament as mask on standard PCBs, which says it adheres well to the copper, unlike some other filaments. http://3dprint.com/11367/3d-print-copper-circuit-board/ Or one could substitute a laser cutter for the extruder head, and subtract copper directly... :) – TextGeek Jan 22 '16 at 20:47