Re: First print on Al
And an observation form my side: I sanded my latest batch (both plywood and aluminum) and I was really excited about the ultra-smooth velvety surfaces - so beautiful on their own that I hung some up around the house. The place looked like a Ryman exposition! Well, I should have left them all alone, because as soon as I started gumprinting I noticed that the white areas were all stained. The things looked really dingy. Now why would smoothing out the brush-strokes cause staining? I'm going to try increading the gelatin size. If that doens't work, I'll keep the brushstrokes.
Rajul, pumice is readily available from printing supply houses. You might try wherever you got your aluminum. I get my aluminum and my pumice from Uniform Graining in Chicago.
2009/3/22 Loris Medici <firstname.lastname@example.org>
A new observation by my side: yesterday, I prepared a new sheet using
another brand (Talens) of acrylic ground and ta-da!... I got those water
bubbles too. It seems something related to acrylic gesso
brand/formulation. The one which didn't give me problems was Daler
Rowney's System 3 (not Cryla!) Acrylic Gesso. If I get it correctly,
System 3 is the student grade product group from Daler Rowney.
BTW, I sanded the surface with 180 then 600 grade sand paper and it's
really ultra smooth one -> I'll see how it prints tonight (or tomorrow
Keith also mentioned water bubbles and he uses Liquitex if I'm not
mistaking. Try to find Daler Rowney System 3 Acrylic Gesso.
Can you please elaborate more about color merging?
22 Mart 2009, Pazar, 6:24 pm tarihinde, Rajul yazmış:
>> 20 Mart 2009, Cuma, 12:54 am tarihinde, Rajul yazmÄ±Å�:
> Loris and Keith.
> The gesso I used was Stevenson's acrylic gesso. If this is the
> problem, I will switch to Liquitex.
> Will try a thinner mix and see if pumice instead of CaCO3 will
> diminish the super-white.
> I have still to find a source for pumice locally - Keith, where did
> you get yours from?
> The uneven gelatin spread does not seem to translate into any
> observable discrepancies.
> However, the colors do not merge between passes as they do on a paper
> medium. So one has to pre-mix color combos to get desired effects.
> I add everclear along with HCHO before spreading.
> Will use a roller instead of a brush.
> The Al plates were discards from a printing house. The new batch I
> have is thinner than the previous one and I will make doubly sure
> that they are squeaky clean before priming them.
> Many thanks! Rajul
> Once again, Thank you. Rajul
> On 20-Mar-09, at 12:47 AM, Loris Medici wrote:
>> Yes, I feel got a hold on it with this trial -> I'm very excited
>> about the
>> next ones... (Have to fiddle-a-little with the negative first.)
>> Adulterant: Calcium Carbonate - since it isn't supposed to be
>> there... (At
>> that concentration.)
>> I don't get this bubble thing, I haven't experienced something like
>> Are you using the same acrylic ground as Keith? (Liquitex.)
>> Try to decrease gelatin strength + add some rubbing alcohol just
>> application. Maybe it's too strong and sets before you finish
>>> LORIS - It must feel good that the first print is done.
>>> What is adulterated gesso? What color does the adulterant impart to
>>> the ground?
>>> After 2 gum passes, the first of my prints cracked in one spot, and
>>> small water bubbles are still visible. Perhaps they will be less so
>>> after further passes. The texture of the brush-applied ground and
>>> brush strokes from the gum emulsion actually seem to lend a different
>>> kind of interest to the print.
>>> Application of a 4% formalin-hardened gelatin was uneven (unlike that
>>> on paper media) but this is not very obvious in the print-in-
>>> KEITH - can you provide the composition of the thinner gesso mix you
>>> use and how many layers of it do you apply? How many gum passes does
>>> your gessoed Al allow for?
>>> JUDY - the gesso-gelatin size seems interesting but the difficulty in
>>> using it with Al sheets seems to lie in keeping the size molten
>>> through the application of multiple coats of it with a roller.
>>> Thanks for sharing your experiences. Rajul