Re: Mixing a light pigment for gum and now acrylic medium

About this list Date view Thread view Subject view Author view

From: Christina Z. Anderson (zphoto@montana.net)
Date: 04/15/03-06:46:59 AM Z


From: <FotoDave@aol.com>
> Chris,
> I think the leprous effect is due to too much dilution that the medium
cannot
> form a continuous film. The acrylic manufacturers do warn about too much
> diulation, and they call this "mud crack" effect (if you look at a whole
big
> area, it does look like mud cracks somewhat.
> I almost never use 1 coat, always 2 coats or more. Maybe it is just
> psychological or the effect of engineering training which says that
averaging
> even outs random noise.
> But considering your test, the first test was 1+1, the second 1+9. The
jump
> is high. I would, for example, test 1+1, 1+3, 1+6, 1+9 at the same time.
> Dave S
>
Dave, Jack B, etc.,
     Never would've thought of this, Dave, and will try that for sure in
several days when I'm done teaching for the week. That could very well be a
problem at the 1:10.
     And Jack, your wondering about something changing in acrylic medium
nowadays...that is interesting.
     I have been using Golden UV Varnish glossy now for the last several
weeks *over* my prints with good success--enough of a gloss to make it
deepen, not too much tho. And what is funny is it is surprisingly spring
fresh scented like another product I know well--Future floor polish :). Of
course, Future is very thin and Golden thick like Karo syrup.
     But under a print--glossy? I just betcha they have discovered some new
polymer thingy and changed their formulations...
     Here are my notes on acrylic medium for a sizing (from my manual I'm
writing):

"Sizing with acrylic:
     All kinds of choices here, but make SURE not to use glossy or your gum
will completely flake off the base--I know, I sized a dozen pieces of paper
this way and learned by experience what NOT to do.
     Use Liquitex Gesso 1:1 and paint on the paper. As Gesso has a rough
tooth, the gum emulsion adheres to the paper quite well.
     Others use 2 parts Gesso/1 part matt medium/ 1 part water. Still
others recommend 2 parts gesso to 5-8 parts water, Scopick being one.
      Use a matte, water-based ACRYLIC DISPERSION at a very high dilution
for sizing. For a glossy finish, the GLOSSY dispersion works. It is called
"K6" available from www.kremer-pigmente.de. For sizing use 1:30 to 1:20.
     Use Golden or Liquitex acrylic matte medium 1:10, two coats, especially
on the more absorbent printmaking papers (Lenox, for example). Those who do
this method say that if staining problems persist after 2 coatings of 1:10
the paper is perhaps not ideal, or the pigments used aren't. One gum
printer says he never had staining problems after he switched from tubed
colors to powdered pigments.
     Also, acrylic-sized paper seems to need an extra "size-replenisher"
down the line if you're doing multiple coats, so you may want to resize
after the first gum coat dries and then after the third.
     One user says he uses a dilute solution of 50% water and 50% acrylic
matte medium, brushes this on the paper, and when dry - just a few
minutes - coats with his emulsion. Kind of a "brush-and-go".
     My own experience with acrylic is mixed. It is such an easy method to
use! But I find the gum doesn't adhere well to the 50/50 dilution. The
1:10 dilution works OK but the gum can adhere unevenly to the sized surface
where some of the acrylic has sunk into the paper fibers and other places it
hasn't. If you brush develop with most acrylic methods, you will get a very
gritty look. I think if I had a choice of brushing on a sizing I would
choose to brush on hot gelatin. But hey, in a pinch, it'll work, and maybe
you'll find it is your size of choice."


About this list Date view Thread view Subject view Author view

This archive was generated by hypermail 2.1.5 : 05/01/03-11:59:54 AM Z CST