Re: brush vs tray size for gum
Jack,
That is correct. I am rolling the rod, not pushing it.
Sandy
At 3:03 PM -0400 10/3/06, Jack Brubaker wrote:
Sandy,
So you are rolling the rod not pushing it along. As I recall the
illustrations I've seen for "puddle pushers" had handles so would not roll.
I would have thought that the rolling motion would pull up the gelatin
behind the rod. But apparently not. Thanks for the info.
Jack
From: Sandy King <sanking@clemson.edu>
Reply-To: alt-photo-process-l@usask.ca
Date: Tue, 03 Oct 2006 00:22:48 -0400
To: alt-photo-process-l@usask.ca
Subject: Re: brush vs tray size for gum
Jack,
I use a 1"-12, 1/2" diameter rod for coating
paper for carbon final support. This leaves a wet
coat height of about 0.4mm.
Before coating the rod is placed in a tube with
hot water at about 130ºF. I spread the gelatin
solution over the paper, usually about 22"X29",
and quickly even the solution by hand or with a
brush. Then, I roll the rod over the paper. As
the hot rod passes over the surface of the paper
it levels the gelatin coating, and at the same
time, dissipates bubbles. I add the hardener to
the paper just before coating, as Kerik described.
The solid metal rod holds heat much longer than
glass, either tubes or solid, and is much more
effective for my use. I suspect the same would be
true for coating papers for gum printing.
Sandy King
At 4:53 PM -0400 10/2/06, Jack Brubaker wrote:
Sandy,
What size rod and what thread do you use?
Jack
From: Sandy King <sanking@clemson.edu>
Reply-To: alt-photo-process-l@usask.ca
Date: Tue, 26 Sep 2006 17:42:26 -0400
To: alt-photo-process-l@usask.ca
Subject: RE: brush vs tray size for gum
I also size papers for gum using 3-5% solutions and adding just a bit
of Formaldehyde to the solution just before coating. I used to use a
brush, but this caused a lot of bubbles. I switched to a threaded
rod, which I heat before running it over the solution, and this
completely eliminates the bubble problem because the warm rod
dissipates the bubbles on contact. This is a technique that I adopted
from coating carbon tissue.
I am using more solution per given paper area than would be required
for gum printing, but I think this should not matter in practice.
Sandy
Carmen,
The largest print I've sized is 20x24. But, if I was going to do 22x30, I
would make a 22" glass coating rod and
apply the sizing with the rod, then
use a brush to fix any areas that were either too thin or too thick. This
makes the process go very quickly so the
gelatin doesn't have the chance to
harden. I would also use formaledehyde rather than glyoxal to prevent
yellowing. When using a glass rod, first place a towel on the table
underneath the paper. This will greatly help keep the rod in good contact
with the paper, especially for larger
prints. I would guess about 30 ml of
>>>> 3% gelatin with 18 drops of hardener would do it.
Kerik
www.kerik.com
Original Message:
-----------------
From: Carmen Lizardo carmenlizardo@yahoo.com
Date: Tue, 26 Sep 2006 12:51:12 -0700 (PDT)
To: kerik@kerik.com, alt-photo-process-l@usask.ca
Subject: RE: brush vs tray size for gum
Dear Chris and Kerik,
I would love to brush size my paper, specially because
use a full sheet of 22x30 inches when I print, and you
could only imaging how long that takes and how much
gelatin I need, but I can't seem to be able to get an
even coat, and mixing glyoxal and gelatin together is
out because I have to able to rise it off the gelatin
to prevent yellow stains. Of course when I used Glut,
it was from black magic and that did not work. I also
felt it in ky eyes and throat and i not even the
>>>> sensitive type. I am willing to try again, maybe with
a different glut?? Any pointers that you can give me
with the brushing?? I was thinking that it had to do
with the size of my paper. The gelatin gets hard
before I have time to cover the whole 22x30 sheet.
Thank you kindly,
Carmen
--- "kerik@kerik.com" <kerik@kerik.com> wrote:
Chris,
I agree that tray sizing is a lot of mess and hassle
for no substantial
benefit. Plus, why do the sizing in 2 steps when it
can be done in one? I
use either a glass rod (puddle pusher) and/or a
brush. I add the hardener
(formaldehyde in my case) to the sizing just before
sizing each print.
Three drops of formaldehyde and 5 ml of 3% sizing
easily does an 8x10 to
11x14 print. In these tiny amounts, exposure to
formaldehyde (or whatever
hardener one uses) is minimal. I get very even
sizing this way. A little
bit of curl to the paper, but nothing that causes
any problems.
I tried B.M. glut and did not like the results. It
resulted in slower
development and considerably more staining than with
formaldehyde.
As for sizing with unhardened gelatin, that sounds
like another in a long
line of T King's erroneous hyperboles.
Speaking of gum, I taught a gumover workshop in
Philladelphia this past
weekend for www.projectbasho.org. On sunday it was
80 degrees F and 82%
humidity in the darkroom. That's the first time I've
printed gum in
sauna-like conditions and it created some hassles
with very slow
development and the need to intervene with some
brute force measures
(brushes, fingernails, sandpaper). Anybody have
similar problems printing
gum in high humidity? The conditions seemed to
cause problems with the
sizing in particular because development was much
closer to normal when I
did a single coat of gum on unsized paper right out
of the plastic bag. I'm
speculating that the humidity either prevented the
gelatin from hardening
completely or it allowed the gum solution to soak
into the sizing a bit
rather than sitting on top. Despite the problems, I
believe a good time was
had by all. Although I always want things to go
smoothly during the
workshops, it's good for the students to learn how
to deal with problems
when they come up.
Kerik
www.kerik.com
Original Message:
-----------------
From: Christina Z. Anderson zphoto@montana.net
Date: Tue, 26 Sep 2006 08:08:22 -0600
To: alt-photo-process-L@usask.ca
Subject: brush vs tray size for gum
Hi All,
This weekend was time for sizing paper, and since I
was doing small sizes
(11x14's) I decided to tray size instead of brush
size to see if it had any
added benefits to brush sizing.
I was sizing with gelatin glutaraldehyde as usual.
I did use a piece of it
>>>>> right away, same day, and had no problem with the
sizing not being hardened
and producing "magenta squares" as did Carmen.
However, I was using glut
that I bought from a medical supply house (now
available at the
Photographer's Formulary) and not Black Magic. The
gelatin on my paper was
not slimy in any way so I know it was hardened. I am
still not sure why
Carmen got that problem, and am wondering about the
suitability of Black
Magic, therefore, with its added sulfite. It sounds
like the same result I
had when I tried Terry King's advice to use
unhardened gelatin and got
black
squares.
With tray sizing and cautions with glut, I gelatin
sized the paper first,
and then the next day I soaked the sized paper
OUTSIDE in a tray of 50ml
glut to a gallon of water. That worked well, but I
>>>>> would only tray size if
the hardening part could be done outside to minimize
fumes produced by the
surface area of a whole tray of hardener, whatever
type--glut, gly,
formaldehyde. (When I brush size I keep the solution
capped inside a
thermos
and pour out a cup at once.) The gelatin paper went
in "slimy" feeling, and
went out unslimy.
The paper works fine but I learned a couple things:
paper tray sized with
gelatin will sink to the bottom, not float as does
brush sized paper
(except
Arches) so if I am going to leave the paper soaking
for a while it needs to
be face up. I learned that the hard way. Back to
floaters and sinkers, Mark.
The paper does curl less than brush sized, but it
doesn't seem worth the
added trouble of trays. This is the only benefit I
can see. Oh, maybe more
evenness of sizing? I don't know this one
yet...will have to print all
papers.
My husband set up an ingenious "clothesline" for
me--a rung ladder on its
side has plenty of hanger-ready rungs.
I learned another thing the hard way: I printed 4
prints on the unsized
but
shrunk paper with a cyanotype layer, put the paper
through the hot gelatin
sizing process and didn't THINK that the
140-whatever degree gelatin would
shrink the paper even more and make registration a
B---H but you bet it
did--warped and shrunk. Luckily only 4 prints
ruined. DUH. Or, as Clay
says,
DOH.
The bottom line is that brush sizing is sooo much
easier and works well and
uses way less gelatin--I sized 24 11x14s with a a
liter of 3%, and normally
I can do that many 16x20s with the same. I don't
think even with small
sizes
I would tray size...
That's all my truly exciting weekend experience!
Chris
CZAphotography.com
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