Homebrew PCBs

> Mucilage sounds better because there is much less water in it.  I
> suspect the trick is to get a very thin and even coating.
> 
> I may have to hit the drug store for some cheapo hair spray.

What about hair gel? You can get that stuff pretty cheaply. It dries
hard like hairspray and comes out with water. Possibly use an ink
roller, or some other kind of stiff foam-rubber roller? Basically we
are looking for a water-soluble varnish here. I guess it remains to be
seen if this pathway offers any improvement over photo paper. Though
typically, photo paper is very thick and close-grained, making it
difficult for the water to throughly soak into the printed side. If
mucilage or guar gum or something can be impregnated into a thinner,
more porous paper, perhaps it will soak through much faster and not
leave any clay residue. I get the impression that this is what the
mucilage guy is experiencing.