Conductive...

KaosKidd

paper.
I seem to recall, someplace, someone had a produce that could be used to draw (with a pen type device) with some special ink that would produce, on a special paper or something like that, a working PC board. Sort of a conductive ink that could be used to print a circuit board, then punch holes through it for connections to the devices. Did I just dream that or is there a product like this?

KK

Leon

Some people in the Homebrew PCB Yahoo group have experimented with direct resist application using modified ink-jet printers.

localroger

They make etch resist pens (which bear a striking resemblance to Sharpies) which you can use to draw your circuit on copper-clad board, then dunk in acid to etch as usual. Radio Shack used to sell them but you'd probably have to order online now.

And they also make conductive ink pens for drawing circuits directly; here's one...

http://www.mcmelectronics.com/product/CAIG-LABORATORIES-CW100P-/200-175

I don't think you could solder to those traces, though, and they are VERY expensive. I think they are meant mainly for repair and changes.

WBA Consulting

I have done it with a "CircuitWorks® Conductive Pen" to "draw" traces up two sides of an N-Scale light pole with a tiny SMT LED on the top. It worked, but I had to use quite a bit and so it altered the look of the light pole enough where you could tell that modification occurred. I did not do anything else with the project. My intent was to make N-Scaled street lights that were true to life as far as functionality. Plus, now you can buy N-Scale traffic lights that are ready to go.

http://www.chemtronics.com/products/product.asp?r=1&m=2&id=7

kwinn

Silver Print is a conductive ink like liquid that can be used to repair damaged boards but I do not think you can solder components to it.

Don M

Actually I have repaired mylar type keypads used in home appliances like a microwave oven. I used a silver conductive paint that I purchased from an automotive parts store. They use this paint to repair the rear window defrost traces.

LoopyByteloose

My impression of the original posting is that some sort of additive process was what he wanted, not the usual subtractive process of removing copper.

About the only one that comes to mind is electroplating. And that would mean that whatever is used as an ink would have to conduct electricity and also create a permanent physical bond to the surface it was written on.

There are metallic markers that may qualify (you see these as gold and silver paint markets), but you would have to go to a jeweler's supply for plating chemicals. Obviously, this wouldn't work on plain paper as the whole has to be immersed in a chemical bath for the plating process.

KaosKidd

Thanks everyone...

For some reason I was thinking of something that was in the ink, and you printed the circuit on paper or something.

Just thinking if there were a "better" way of making PCB's that all..

Thanks again everyone!

KK

Tubular

KK,

1) Ink plotting
There are many metal laiden conductive inks out there, even more with RFID demanding high conductivity. One thought that springs to mind would be to buy a cheap serial driven plotter (eg HP 7475 or similar) off ebay, and have a play. You probably need an ultrasonic cleaner to clean out the pens. You could play with additive (metal inks) or subtractive (photoresist / "dalo" pen). You can plot direct to copper by sticking it onto a sheet of paper with double sided tape.

2) Laser foil
Several years ago there was a wonderful product called "GeoFoil" that you used with a laser printer to create foil embossed patterns of any shape. It seems to have disappeared from the market, but if you can get your hands on the "silver" colour - its somewhat conductive. I don't think you would do a prop circuit (consuming 80mA+) with it, but I'm sure any of the low power micros would happily work with it. You'd need conductive glue to hold the parts down, but that is easy enough to come by.

3) Conductive Polymers
There are some polymers that are getting very conductive (impressive, for something "plastic"). Some of these are transparent. These can be deposited using inkjet printheads. Unfortunately I arrived too late here to get one of the Parallax inkjet kits from Matt Gillilands work, otherwise I'd be pushing some of these polymers through...

Finally the whole printed electronics scene is fascinating. I note you're in PA... right now there's an interesting exhibition in Boston MA that I'd love to be at. Info here http://www.idtechex.com/events/

markaeric

What about creating traces with adhesive copper tape? You might even be able to use a combination of conductive ink and copper tape - since you can solder to the tape (and it's adhesive is usually conductive). Or were you thinking of an automated process?

KaosKidd

@Tubular and markaeric

I was looking for something along the lines like a plotter with "special" ink or something like that... Draw or get a bit map of the image and "print" a PCB of sorts. Everything that I've seen won't support heavy draw (100 ma's).

The whole idea of simplifying PCB for the hobbyist has my attention. I had envisioned "pristine" aligned layers printed and "glued" to form a multi layered board.

I'll search for the plotter idea tho, who knows what I'll find. And I wish I could attend but luck has other things planned for me.

KK

Thanks!