To achieve enough conductivity, they use Silver primarily. Carbon based glues haves a resistance from few hundred ohms to several Kohms. Hence the price
--- In Homebrew_PCBs@yahoogroups.com, Jan Kok <jan.kok.5y@...> wrote:
>
> Chemtronics CW2460<http://www.digikey.com/product-detail/en/CW2460/CW2460-ND/2098937>silver
> epoxy is "only" $170 for 20 grams from DigiKey. It has a work life
> of 60 minutes.
>
> I've used MG Chemicals
> 8331-40G<http://www.digikey.com/product-detail/en/8331-40G/473-1142-ND/2805409>silver
> epoxy ($97 for 40 grams or $51 for 14 grams from Mouser). It's good
> stuff, but I wouldn't recommend it for this application because the work
> life is much shorter.
>
> You might be able to make your own conductive epoxy, using your choice of
> epoxy (appropriate work time, probably want heat curable) and a conductive
> powder, perhaps tin or carbon.
>
> There are also conductive ink pens for about $50 a piece. Would save you
> the trouble of coming up with an applicator nozzle.
>
> On Sat, Mar 2, 2013 at 5:34 PM, Mark Lerman <mlerman@...> wrote:
>
> >
> > Final result:
> >
> > After a difficult set of interactions with this definitely non
> > hobbyist friendly company (Master Bond), I was finally given the
> > price of this epoxy - $500 USD for 10 grams!! Needless to say, I'll
> > not be experimenting with this product. On to other things!
> >
> > Mark
> >
> >
> > At 08:36 AM 2/18/2013, you wrote:
> >
> > >Here's a link to a conductive epoxy that is one part and can be
> > >diluted with acetone. It is heat cured. So, theoretically one could
> > >"print" the circuit, stick the components on and cook it to cure the
> > >epoxy. It appears that it would work, but there would be considerable
> > >development time involved in designing the proper "applicator".
> > >Something like a solder paste applicator might do. I asked for more
> > >information, but master Bond is not really hobbyist friendly. Any
> > >thoughts or comments?
> > >
> > >Mark
> > >
> > ><
> > http://www.masterbond.com/tds/supreme-10hts?utm_source=valentines&utm_medium=email&utm_content=pd-sup10hts&utm_campaign=vrsm
> > >
> >
>
>
> [Non-text portions of this message have been removed]
>