From: Judy Seigel (jseigel@panix.com)
Date: 07/28/03-04:36:31 PM Z
On Tue, 22 Jul 2003, Clay wrote:
> Yeah, the dry dichromate thing obviously really reduces the water in
> the solution, and allows some very heavy pigment loads. I am still
> VERY paranoid about dry dichromate and wear a dust mask and mix over
> the sink so any spills can be washed away....
At the risk of -- well no risk, I am -- sounding like chicken little, I
urge that folks, unless already dying of some incurable disease, NOT use
dry dichromate. It flies in air, it sprinkles in fine grains, it gets
wherever, even just 3 grains you don't need: IT's VERY toxic and very
allergenic and to expose yourself to it every time you make a print is
foolhardy. Bad enough when mixing your sensitizer... (So be sure to wipe
the neck of the bottle after every use.)
OK, Sam Wang makes dazzling prints.... but Sam is not an actual person.
He's a composite of impervious high-end parts . And you're not.
Allergies are insidious, chrome is super allergenic, and if you get
sensitized (it happened overnight to me with turpentine after 15
symptom-free years) it's almost certainly irreversible, and may extend to
other materials. You may also be unable to enter a room, even a building,
where dichromate is in use (I know someone that happened to).
Plus just picture a class with 15 students flinging around am di powder...
In any event, I guarantee it's not necessary, even if it weren't more
trouble. You can get the same effects more easily and the same viscosity
with saturated am di in a squirt from a dropper, or a few mls in a
graduate. I'm also not convinced, if you make a very thick gum, that the
dry di allows a more viscous emulsion...
PLUS, as I may have mentioned a few dozen times, I usually make my gum
emulsion LESS viscous. It goes on smoother & easier (no extra staining (no
matter what that addled gum pigment ratio test claims). And, I point out,
unless you're in the amazonian rain forest, coating a large print with a
thick/viscous emulsion means it's almost certain to get too viscous to
spread/smooth before you finish coating.
This can apparently be taken care of by spreading with a roller -- I don't
doubt that that makes a fine print, but think of the extra emulsion needed
to soak the roller, and the extra water and time to wash it. (A foam
applicator is thinner/smaller, washes almost instantly.)
Tho I will surely try these variables as soon as I get all the equipment,
and I applaud Melvin as improviser-innovator (tho beginning under a
misconception, about which more anon) -- it sure sounds to me like a
REALLY hard way to make a gum print...
Now, however, just for the record, will the Sam Wang figure please explain
how he weighs those small amounts of dichromate (question asked but not I
think answered) ?
cheers,
Judy
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