Conductive Ink... anyone try?

Started by Triffid, January 30, 2004, 11:01:58 AM

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Paul Perry (Frostwave)

Coincidence: I saw in a trade journal today that Epsom have been experimenting with conductive printing ink & have made a *fourteen layer* :shock: pcb, with alternating insulating ink layers!!
I hate to think how much a cc of THAT ink will cost :x

I think I'll still be using stripboard for a while yet.. I can imagine conductive printed PCBs being great for high impedance SMT work, though.

I wonder if it is possible to get powdered metal to stick to a photocopied trace on paper or cardboard? If you had metal powder spread on a surface, and put a photocopy or laser print face down & ironed hot enough to melt the toner, then the metal powder would stick to it!
Hope nobody has patented that! GO FOR IT :lol: MAD SCIENTISTS
hint: think nickel powder, most other metals have oxides on their surfaces or other problems.

aaronkessman

yes, many are working on printable conductive inks. it's an entire mess getting traces conductive enough to be good. you need several printed layers of ink to get conductivity high enough for even the most basic use.

plus a multi thousand dollar machine with special print heads and hardware/software to make it.

it will probably never reach the level where you can buy a canon conductive ink print head and plug it into your regular desktop inkjet.

Ink is SUPER expensive. not for the DIYer.

bass_econo


aaronkessman

update-

I first started working with a Chemtronics pen - http://www.tselectronic.com/chemtronics/cw2200.html?tse_Session=8968b606d6be30ebbb1ca44798267d03 . Now i'm working with a Techspray brand pen http://www.intertronics.co.uk/products/tec2505.htm . The techspray is FAR better than the first one I was reporting on. Old stuff was more flaky, had a wider tip, and adhesion wasnt as good. Not that it was BAD, but the new stuff is better. So if you want to draw traces, I recommend the Techspray brand.

Anyway, the stuff is pretty low viscosity and even with the fine tip, you have to be careful when drawing traces on perfboard or they'll bleed everywhere! You need the gentlest of taps. If it does bleed, you need to wait till it dries a little bit first (when it's more vulnerable to flaking off) and then scratch it into shape with a razor. But otherwise it's pretty good.

You can definitely follow a PCB pattern, as I am doing with the Tremulus Lune. You can also definitely solder to it pretty well at low heat. Not sure how low because they dont provide a number on the datasheet. Just to be sure I'm going over junctions with the pen again.

Overall, because of the pad-per-hole board, you end up drawing a surprisingly little number of traces. not bad.

Curing at 150ºC for 5-10 minutes increases conductivity too.

I dont know if I'll be able to show pictures, but I'll try.

Aaron

aaronkessman

Ok, I've got a picture of my Tremulus Lune board made with conductive ink traces on perfboard. It's mostly the drawn traces, but I used solid wire for the V+ and V-. Layout follows the PCB pattern on the commonsound website.

The pic is up on yahoo, hopefully no one is too interested and bandwith isnt exceeded  :roll:

http://pg.photos.yahoo.com/ph/fuzz_a/detail?.dir=2fef&.dnm=1213.jpg&.src=ph

worked out well - kind of like half regular perf, half not. it's little messy, but it works and my technique can surely be improved.

Aaron

puretube

interesting!
Colin will like to see that, too...

Paul Perry (Frostwave)

thanks for the report, AaronK! this could open up DIY to people who for some reason are unable to solder. eg in grade school where there is fuss about using dangerous materials & equipment, plus it is safer to use a pen in bed than an iron!
I would have bet $$ it would not have worked, so I have definitely learnt something!

javacody

That looks promising. From the looks of it, the pen must have a very wide tip. Do these come with a finer tip?

aaronkessman

Paul - well, i wouldnt go that far. You still need to solder the leads to the board and pots/jacks, and the components to the perfboard. also, the fumes are hazardous, but probably less so than solder fumes. There is also no lead. Still, i would not recommend doing this in bed!

javacody - yes, it is a surprisingly wide tip. It is narrower than the first pen i tried, but the material is such low viscosity that even a finer tip is not fine enough. I dont know if they have anything finer. surprising since it's made for repairing PCB's which have much finer traces than perfboards....

but the lune is up and running and it's the best and most versatile tremelo i've ever come across or imagined.

I'll add my build report to another thread.,..

Aaron