Re: Printing gum on hard surface

No, the problem in hardening a thick layer doesn't have anything to do
with glass; you can't do it on paper either, IME. Gum simply won't
harden in a block or a thick layer the way gelatin does, IME. Of course
you're welcome to prove me wrong. :-)
Katharine

Dave Soemarko wrote:
>
> Hi Katherine,
>
> But when you said you exposed it long time, did you mean expose the gum that
> is coated on glass for a long time? And since the glass is so "slick" the
> gum didn't hold to anything as you said/saw.
>
> My suggestion (and again, I don't know if that will work) was that you
> prepare a thick gum layer on porous paper, expose it heavily, and wet it
> briefly and squeezee it on a piece of glass (or mylar might be even better).
> Keep it there for a few minutes or even an hour, then wet the back side of
> the paper or soak it in water, and then peel it off; and then soak the glass
> or mylar under water and wait for the unhardened part to dissolve while
> leaving the hardened piece there. This has to be very carefully done,
> otherwise the hardened part will be washed away too. Basically a carbon
> transfer method.
>
> But that is if you are interested in a piece of hardened gum. If not,
> probably your test on mylar or non-glare glass is sufficient.
>
> And typing this is making me so wanting to do some tests, but maybe I should
> not....
>
> Dave S
>
> ----- Original Message -----
> From: "Katharine Thayer" <kthayer@pacifier.com>
> To: <alt-photo-process-l@sask.usask.ca>
> Sent: Friday, September 03, 2004 7:37 AM
> Subject: Re: Printing gum on hard surface
>
> > Dave Soemarko wrote:
> > >
> > > > The chemist I'm working with thought it would
> > > > be a simple matter to coat glass with dichromated gum, expose, wash
> and
> > > > dry it and then peel off a sheet of nice hardened gum. Don't I wish!
> > >
> > > Oh, sorry I didn't read this email before replying to the previous one.
> If
> > > you want a piece of dry hardened gum, maybe you could try coating it
> > > thickly, expose, and do something similar the carbon transfer, except
> that
> > > this is a gum transfer. You can transfer it to a piece of pure glass, or
> the
> > > slick side of mylar.
> > >
> > > But I haven't done that myself. It's just a suggestion.
> > >
> >
> > Well, I actually tried that in the interest of making more hardened gum
> > faster, but I couldn't make it work. I don't think gum works the same
> > as gelatin in this regard. And in fact, we all know that one reason for
> > failure in gum is to get the coating too thick; it just flakes off. I
> > put these thicker layers out in the sun and exposed them for a very long
> > time, but no go.
> > kt
> >
Received on Sun Sep 5 08:30:30 2004