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[on:]

There is a new article about 3D printers in the mainstream press, in fact there were a few additional ones a couple of days ago because some guy irritated the libs by printing out gun parts but that is a different story:

http://news.yahoo.com/3d-printers-conquer-consumer-market-144226050.html

It occurs to me, has anyone tried to use this technology for PCBs?  Or is there just no way to get good conductive tracks?  Because it would make all the sense in the world to make PCBs this way.  Printers can put down fine tracks, you could easily have multilayer boards, blind and buried vias, etc.  Anyone have any insider info they want to share?

[Reply #1 on:]

They have been used to route out copper from plated PCBs, cut out the part that etchant would normally remove.
I have not seen that appleied conductive material to bare material (such as fiberglass sheet) to make a PCB.

Before PCBs, we used to have PWBs - where actual wire was put down for the traces. Like in the 80's.

Glueing double sided boards together with B-stage material in between has been the norm for quite a while.

[Reply #2 on:]

At high frequencies wire and flat trace have some different characteristics that make flat traces more desirable, but time has robbed me of just why.

The hard part would be what you print flat, continuous conductor with that can compete with etching? How conductive is sintered metal?

 

[Reply #3 on:]

They have been used to route out copper from plated PCBs, cut out the part that etchant would normally remove.

That's a machining operation, not a 3d printing operation (subtractive vs. additive).

There's an outfit that makes a "PCB plotter" that is a desktop CNC mill for making PCBs.  With all the optional accessories you get the capabilities to do plated through holes and double sided boards, but IIRC it was around US$20k for the whole kit.

-j

[Reply #4 on:]

They have been used to route out copper from plated PCBs, cut out the part that etchant would normally remove.
I have not seen that appleied conductive material to bare material (such as fiberglass sheet) to make a PCB.

Before PCBs, we used to have PWBs - where actual wire was put down for the traces. Like in the 80's.

Glueing double sided boards together with B-stage material in between has been the norm for quite a while.

I have seen milling machines that do this and I was looking into this intensively a while back, but in this case I am talking about 3D printers, not milling machines.  It seems they would be even better than milling machines because printing, if it is possible to do at all, would allow for multilayer boards without having to align and bind layers together, along with the through, blind, and buried vias.  It would be so powerful it would be revolutionary.  I was just wondering if anyone knew what the state of the art on this was.  Lots of people are using the milling process - I learned about it in the book 'tinyAVR Microcontroller Projects for the Evil Genius' where the authors used a mill to make all their PCBs and explain the process in an appendix.

[Reply #5 on:]

The PWB process allowed the wires to be stacked up, crossed over, etc. Didn't have layers of cards.
As I said tho, its been surpassed by gluing multilayer cards together.

[Reply #6 on:]

The PWB process allowed the wires to be stacked up, crossed over, etc. Didn't have layers of cards.
As I said tho, its been surpassed by gluing multilayer cards together.

...or has it...?

http://www.panasonic.com/industrial/electronic-components/printed-wiring-boards-devices/boards.aspx

Well, maybe that's not the same thing, but on the wikipedia page for "printed circuit board":

http://en.wikipedia.org/wiki/Printed_circuit_board

...they mention a (patented) process called "MultiWire" which sounds close to what the OP desires (in a certain manner), which was (per the article) still available from Hitachi as of 2010 - I found this:

http://www.hitachi-chemical.com/products_pwb_05.htm

So maybe it is still possible to get...?

Other than the patented process, I wonder how difficult it would be to homebrew a machine to do something like this (probably not easy, certainly)...

/loved the old "cordwood" PCB fab method shown on that wikipedia page...

[Reply #7 on:]

Some people in the reprap project have tried this. They printed a plastic circuit board with channels for tracks and filled them in with another extruder using Field's metal at first then solder later. Take a look here: http://blog.reprap.org/2009/04/first-reprapped-circuit.html

Might not be quite the level of precision you had in mind though

[Reply #8 on:]

Maybe take the reprap idea and use solder paste to fill the track, either from syringe that squeezes it out under printer control also, or hand squeegied out like when applying paste with a mylar/steel stencil.

[Reply #9 on:]

The Panasonic link above mentions using copper paste. Could you solder to that later?

[Reply #10 on:]

loved the old "cordwood" PCB fab method shown on that wikipedia page...

The original Boeing 747 passenger service/entertainment mux system components had several cordwood modules in them.

I used to marvel at how the hell they got all the components leads through the holes on the second side pcb !

I had to do a similar task recently, feeding 75 diodes leads through holes in a pcb ( because I havn't found an edge connector yet to fit the BCD switches I use )  but at least the board was quite big compared to the little cordwood modules .....

[Reply #11 on:]

Just thinking about this pcb making.

What if an old Lexmark ( or whatever ) inkjet could be modified to pull a plain piece of heatproof board through ( instead of paper ) and the print head replaced with a nozzle pushing out tiny drops of copper in a solution or paste.
It would probably have to be very slow, but then the board could be flash heated to remove any solution, and fuse the copper particle together ?

Just excercising the brain before a busy day :-)

[Reply #12 on:]

There's industrial 3D printers that fuse powdered metal into solid metal.

[Reply #13 on:]

Thats interesting,  perhaps after the first layer, you put a punched ? silicon sheet on top, and build up the vias through the holes, with the layer 2 tracks on the top?

[Reply #14 on:]

I'd have the parts clipped into a 3D printed plastic frame then form bare wire right up to the join on leads and socket pins, no need to solder except fixes. When it's right, coat the wires and box it or just pot it. And while I'm wishing for so much pie, it should be able to connect to surface mount.