I, too, have this little voice inside me, which ever since I read your
notes has been urging me to try them, especially the three coats (oh, I
faint) of size... I'm fighting the urge, you understand, but I have a
bunch of questions anyway, which perhaps you will indulge...
On Fri, 26 Jun 1998, Arthur Richards wrote:
> I've been asked to tell how I do gum printing. Ok here goes. First I
> have to say that I work for a newspaper in central Illinois and that my
> negatives are fairly easy to obtain. we have a machine called a pelbox
Is a "pelbox" something new, or old? Is it bigger than a breadbox? What
size negatives does it make? Are they in halftone dots? Why don't we
have one?
> that prints out negatives,and these negatives are very thin, I can get
> b&w negatives or color separations and they will easily print the
> detail. another method of obtaining negatives is that I expose 8x10
> sheet film with a slide about 2 seconds stopped all the way down then
> develope the neg in hc110. I try to find a paper that works for me and
> just stay with it.I don't print on wood, tiles, pillowcases or anything
Would you mention by name any of the papers that work for you?
> else but 100% rag content drawing paper, after all one of those little
> voices inside me that won't let me stop doing this says it has to last
> thousands of years or it's not worth it.When I have the paper I
> preshrink it in hot water, dry, then I get knox gelatin ready and as hot
> as I can stand it. I dip the sheets of paper in the gelatin, let it dry,
> then dip it in formalin to harden the gelatin. I do that procedure 3
> times and the formalin three times, then I print on it. I use a 10%
Your description of 3 times in the gelatin and 3 times formaldehyde is
formidable, the first I've heard of 3 times... What led you to that...
trial and error? Or just for good measure? Or someone suggested it? I'm
especially curious because I've found even twice in gelatin makes the
paper boardlike. On the other hand, you absolutely cut out one problem
that way, which is the paper continuing to change size. I would imagine
that by the 4th wet & dry (3 with formaldehyde) it's got to be stable,
which is a lot to recommend the method. (And would probably obviate the
substrate, which surely is a pain.)
But the thought occurs to me that you may get away with that by using a
weaker gelatin solution to begin with... We've always used 3%, except in a
really cold room I reduce a little... I gather that you don't bother
squeegeeing the paper when you take it out of the gelatin bath. I've
found that if the gelatin isn't really THIN and HOT this helps ensure an
even coat -- but is of course another pain, that maybe could be dispensed
with.
As for the formaldehyde, where do you get it ? perhaps from the newspaper
(the "morgue"? -- sorry there are some things a girl is not meant to
resist). If you've been on the list a while you may have heard mention of
glyoxal.... worth trying when your present supply runs out (tho maybe
newspaper types are reallllly tough).
> solution of potassium dichromate and 5 grams of watercolor paint with
> 25mg of gum arabic. I mix 5cc of each then paint the emulsion on with a
> fan brush, allow to dry in a cool place then expose by contact under 2
You didn't say how much of the dichromate solution you use -- is that 25
cc potassium dichromate solution, with 5 g of watercolor paint from the
tube, and 25 g gum arabic? That sounds similar to what we use, but I'm
curious what pigments... I mean I've found an enormous variation in
covering power -- tho I suspect you have some favorite colors that don't
trip you up... Will you divulge?
> ultraviolet shop lights for 9 minutes then develope in the sink. I let
> them dry and I re-expose them for contrast, but I've never had to expose
> 3 times yet. The book that I basically went by is one by david
Ah, maybe your secret is more coats of gelatin means less coats of
emulsion ?? ;- )
Those "ultraviolet shop lights" are the round bulbs approximately 1000
watts? At what distance?
> skopick-The gum bichromate book but every time I think I know it all I
> learn something new
Amen....
Judy