PVA and printing on AL
We may be comparing apples and oranges wrt printing media, but I have learned a few things by testing PVA as size in making gum prints on Al. Despite quite a few lost plates which were grounded with a mix of diluted gesso, sand flour, gum arabic that were hot air dried, then sized with HCHO-hardened gelatin, I have made a few prints that I am happy with. I attribute the losses to the thickness of the ground. When miracle size (Gamblin PVA) was described by Marek in September (?), I decided to test it. Incorporated into the above ground after the latter was carefully optimized for its ingredients, I compared 1:1 and 1:2 mixes of PVA:ground. (Gelatin sizing was NOT used.) Higher PVA dilutions were more unpredictable. 1:1 left a texturally uninteresting but sturdier surface after gum passes than did 1:2. Development of the exposed gum layer on 1:2 grounded surface created wrinkles of various sizes, graininess from the sand flour, and sometimes lifting of the edges of the ground. Handled very gently, these actually created interesting, even desirable effects. Developing after the 3rd gum pass by gently pouring drops of water from a wetted tissue paper caused lifting of the superficial layers which exposed the earlier ones. This generated what I call the "lichen on rocks" effect which I found serendipitous and charming, and appropriate to the image I was printing. I could do 3-4 passes of gum before parts of the image surface became rough. So I applied 1:2 aqueous dilution of PVA after the 4th gum pass to see if the print could take a 5th one. Although I need to check this out more thoroughly, it appears that re- sizing with PVA between gum passes might re-establish a smooth surface if one is desired. My findings thus far! Rajul
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