From: Dave Rose (cactuscowboy@bresnan.net)
Date: 09/05/03-06:55:38 PM Z
Greetings from Big Wonderful Wyoming,
Judy offers a lot of great advice here. It makes sense to size large
batches of paper - the economy of scale is considerable, both in time and
cost savings.
When sizing paper, I soak the sheets in a tray filled with hot gelatin. The
paper is then pulled between two closely-spaced, varnished wooden rods at an
oblique angle. The rods squeegee or push the excess gelatin off the paper,
leaving a smooth and even coating on both sides of the paper. The process
is repeated, and then when the paper is dry, it's soaked in formalin
(hardener) and hung up to dry. The big advantage with this method is that
if you (or the process) goofs up and you have a bad print, you can always
flip the paper over and make a new print on the same sheet.
I've never used "Kremer Anti-foam", but I can imagine how it would be
useful. Small air bubbles in gelatin can be troublesome.
Best regards,
Dave Rose
----- Original Message -----
From: "Judy Seigel" <jseigel@panix.com>
To: <alt-photo-process-l@sask.usask.ca>
Cc: <alt-photo-process-error@sask.usask.ca>
Sent: Friday, September 05, 2003 2:14 PM
Subject: Re: Gum Woes
>
> On Mon, 1 Sep 2003, Gary Nored wrote:
>
> > I coated several sheets of paper with gum/dichromate
> > solution, omitting the ink. To my surprise, this paper
> > didn't come out white after exposing to sun and washing --
> > it comes out a nice caramel-brown color. Further
> > experiments yielded nice photograms of white and brown
> > (better than the prints with pigment in them).
>
> This point has been addressed, but here's a generalisation (or
> generalization if you have American spellcheck): With my materials and my
> working protocol there was NEVER EVER any advantage to "sizing" the paper
> with gum. I think some folks think it's easier than gelatin size because
> you don't have to watch temp., & harden, and of course there are fewer
> variables... But in the words of the prophet, in this case at least, the
> lazy person's way is the hard way....
>
> If you set up to do a whole bunch of paper (having done a test run of the
> materials first to be certain), and ADD A DROP of KREMER ANTI-FOAM to the
> liter of 3% gelatin, then squeegee with a rod against a glass sheet (from
> the back) the sizing goes very quickly & the coat will be perfect. (I'm
> going to do an exact description with diagrams for the forthcoming #9, but
> will answer any particulars asked in advance.) For "rod" incidentally I
> use an acrylic towel bar about 1 inch in diamter. Works splendidly.
>
> Of course gelatin sizing by brush or foam on one side only is easier, but
> the paper tends to curl & (I find) the size not so even & doesn't hold up
> as well...
>
> In sum: Gum as size had its own character and made a few dandy prints, but
> I found the yield much lower & with an infinite variety of staining
> possibilities, the stain was more trouble to remove (with sulfuric acid,
> btw) than the drill with gelatin -- ie., in the long run a much bigger
> pain.
>
> One other point: it seemed like someone thought "commercial" or
> printer's gums darker than other gums. This is not the case. I found for
> instance Varn gum lighter than most... RBG or Philben house gum is also
> quite light, as are many others... That is, I find "commercial" or
> printer's gums superior to home made, except for an etcher's gum (as from
> Graphic Chemical) -- it has an ingredient that's bad for gum printing.
>
> If you start with a gum arabic powder, of course it will be very light,
> but besides the nuisance of mixing, there's the problem of preservative.
> The lithographers gum we buy by the gallon already has preservative (we
> may not want to know what that is, though I suspect it accounts for much
> of the difference between commercial gums).... and no matter what the
> label says, I've found it keeps well, for my purposes remaining more or
> less the same for years.
>
> Judy
>
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