From: Dave Rose (cactuscowboy@bresnan.net)
Date: 07/22/03-10:57:43 PM Z
Ed, thanks for the concise and detailed report on Stuart Melvin's "New
Methods for Gum". I appreciate it.
As I'd suspected there's really nothing new here other than the addition of
"Miracle Muck". (Or has that been done already?) It sounds like Melvin has
developed good work habits and pays close attention to detail. That's
commendable but it's hardly what I'd call "New Methods". Is gum really so
difficult for most people that a guy who does it well is looked upon as some
kind of guru? Most of these "new methods for gum" are procedures that I'd
tested and used over ten years ago. Read the existing literature and then
experiment.... it's not that difficult to produce large, high quality gum
prints if you really want to.
I don't understand the advantage in adding dry dichromate to gum and then
adding water. Why not just add a 'traditional' dichromate/water solution to
gum? What's the difference?
IMO, there's a lot of overblown hype here. Kudos to Mr. Melvin for some
effective self-promotion, and the obvious ability to make some beautiful
prints.
Best regards,
Dave in Wyoming
----- Original Message -----
From: "Ed Buffaloe" <EdBuffaloe@UnblinkingEye.Com>
To: "alt-photo-process-l" <alt-photo-process-l@sask.usask.ca>
Sent: Tuesday, July 22, 2003 11:35 AM
Subject: News from APIS
The first presentation was by Stuart Melvin on New Methods for Gum
Printing, including some information on platinum printing since
he also does gum over platinum. Stuart is very articulate and com-
municates clearly, so it was a joy to hear him speak. His prints
are extremely detailed, with clarity and gradation rarely seen in
gum. You can view some of Stuart's work on Kerik Kouklis' site at
http://www.kerik.com/swmelvin/. I will outline the information
Stuart presented.
Paper: He uses Fabriano Uno hot press 140 pound, and presoaks it
at 140° for 20 minutes. He presoaks twice for large prints. For
platinum printing he gives a pre-soak in 1 to 1.5% oxalic acid for
5 minutes.
Platinum: For an 8x10 print he uses 21 drops of sensitizer, 8
drops of water, and 3 drops of ethyl alcohol. He applies the solu-
tion with a brush, then drys it with a cold hair dryer. He stated
that good humidity is a plus and that he resizes the paper before
starting the gum-over.
Sizing: Stuart uses a 3% solution of 250 bloom gelatine, adding
ethyl alcohol at a ratio of 1:20 to the water. He also adds 13
drops of formaldehyde per gram of gelatin. The solution is applied
at 125° with a hake brush or a rod in an environment at 60% humi-
dity. The paper is dried for 3 hours. A fan may be used to speed
drying.
Gum: For a typical 8x10 print he uses 10 ml of 14 BAUME gum arabic
and 2 g ammonium dichromate. Lowering the quantity of ammonium di-
chromate lowers the speed and increases the contrast. He pours 2
ml of gum into a mortar, adds the dichromate, and lets it sit while
he measures the pigment. There is no sense in giving pigment quan-
tities, since it varies wildly, depending upon the pigment. Stuart
squeezes his pigment onto the pestle and mixes it thoroughly with
the gum and dichromate. He also adds one drop of Raphael's Miracle
Muck per 2 ml gum (in this case 5 drops) to eliminate flaking. He
then adds the remainder of the gum and a certain amount of water,
which may vary according to need--in this case he added 2.5 ml of
water (25%). He then transfers the mixed solution to a 250 ml
plastic bottle with a large hole drilled in the cap. Over the top
of the bottle he folds a double layer of screen printing material
and screws the cap on. The screen printing material serves to fil-
ter the mixture, assuring that the mixture that goes on the paper
is free from any tiny bits of solid material that might cause
streaks or lumps.
Coating: Stuart coats gum with a 6 inch foam paint roller. He
stated that foam rollers are widely reported to not work with gum.
His comment was: "Anything will not work." His favorite is the WIZ
America's Favorite grey foam roller, which he buys at Home Depot,
but he also stated that the Sherwin Williams white foam roller
will work. He covers a flat surface with some low adhesion tape,
sticky side up, and rolls the roller over it to remove any dust
particles that may be adhering to the foam. He pours the filtered
gum solution onto a glass plate and rolls it out with the roller,
then rolls the coat onto the paper. He starts with relatively
light pressure, which he reduces to no pressure at all--only the
weight of the roller itself--until the paper is evenly coated edge
to edge.
Drying: He dries in 50-60% relative humidity under a low fan for
15 to 20 minutes.
Registration and Printing: Stuart uses pinholes in opposite cor-
ners of the negative to register the image, placing the paper on a
lightbox with a goldenrod or rubylith covering to prevent exposure
to UV light. When re-registering after the first coat, proper reg-
istration is achieved when the image disappears. The correct
drying time can be judged by when the pinholes in the paper line
up correctly with those in the negative. If the paper is over-
dried it will shrink too much. If this happens, he states you can
coat the back of the paper lightly with distilled water using a
hake brush and dry it down to the correct size again. Exposure
times are judged by doing test strips in advance, and by long ex-
perience. Overexposure is the primary cause of failure to develop.
Stuart said that his prints are averaging 5 to 6 coats. Sometimes
he may do as many as 7 or 8 the first time he makes a print, but
for subsequent printings he can collapse some of them--i.e., use
more pigment in a given coat.
Development: He starts with water at 75°, changing the bath 2 to 3
times, increasing the temperature 1 or 2 degrees with each bath.
Drying: He allows the paper to drip as much as possible, then lays
the paper flat and uses a cool fan, never allowing water to puddle
on the paper.
Clearing: The paper must be bone dry, which takes 1 to 2 days, and
then it may be cleared for 1 to 2 minutes in a 1% solution of po-
tassium metabisulfite. Stuart then rinses the print for 20 minutes
and dries as before.
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