FotoDave@aol.com
Thu, 14 Jan 1999 23:49:18 -0500 (EST)
In a message dated 1/14/99 8:34:16 AM Pacific Standard Time, jseigel@panix.com
writes:
> Dave, in my experience less than 3% gelatine isn't a good idea for sizing
> for gum. It probably varies with the paper, how well sized it is to start
> with, or whatever, but when I first began teaching, students had trouble
> with flecks in their gum prints.
Judy,
Yes I think it really depends on how well it is originally sized. I used the
Canford Snow White. I first thought my sizing was so nice, but later found
that even without sizing, the paper clears *very* well with one coat, non-
staining color. With 2 coats, the stain is perceivable but certainly not
objectionable. With 3 coats it is debatable. With 4 coats it is clearly not
good (at least not to my taste).
But with Canford, the 1 to 1.5% gelatine + alum sizes very well even up to 3
coats although I will use 3% in the future. You still have my gum print,
right? Or did you throw it away? ;) The one with tulip and a sharp bunch of
leaves behind... that was printed on Canford with the 1.5% size. Isn't the
highlight still quite nicely white? (I don't even have a copy here, but my
memory says that it clears pretty well).
Recently I have been thinking about another crazy idea. Paper that has not
been sized will work like a blotter. If it doesn't, it must have been sized
(internally or externally). I read that some size materials such as starch
does not respond well to hardening, but often gelatine is used in sizing.
Since Canford already work well for me for one coat, that means it has sizing
already. Does that mean that I can simply harden it without any gelatin coat?
I don't have glyoxal nor formaldehyde since I never needed it (I still use the
food alum that I bought about 20 years ago when I size my riced paper for
painting). Would you be so kind in helping me doing a test? I will send you a
few cut sheets of Canford and Mi-teintes that I have here (so that we are
checking exactly the same thing), and could you just soak it in glyoxal as you
would normally harden your paper? Then I will run some stain tests and report
back to you and/or the list.
Of course sizing with gelatine is not that big a deal either, but saving a
step is saving a step, and I don't like the heating, cooking part....
Dave
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