Re: cyano on gessoed Al
Hi Rajul, I missed this one below, sorry. I use my standard 5% AD concentration for every kind of surface. I expose the Al sheets for the same time as paper. I just purchased agar-agar and will try it on painted aluminum panels soon. The panels are said to be painted with electrostatic powder paint which is melted and cured in special owens. I hope agar-agar will be able to adhere. Do you size the agar agar layer with gelatin (or include some gelatin in the agar agar coating)? This is in my things to try list... Regards, Loris. 11 Nisan 2009, Cumartesi, 9:28 am tarihinde, Rajul yazmış: > Hi Loris, > > When you do gum on prepared Al sheets, what concentration of AD do > you use, and how long do you need to expose relative to paper exposures? > > Looks like I will have to continue building tooth at every step if I > want the colors to blend between successive passes. > > Thanks for your input. Rajul > > > > > > On 10-Apr-09, at 11:52 AM, Loris Medici wrote: > >> Rajul, thanks for the update. I'm very interested in the agar-agar >> stuff >> -> seems to be useful for other things too (sizing paper - from >> Alberto >> Novo - and non-toxic carbon - from Halvor Bjoengaard)... >> >> I currently wait for Henk coming back from his trip -> will continue >> trying with "beer coating" after hearing back from him. >> >> Regards, >> Loris. >> >> >> 9 Nisan 2009, PerÅ�embe, 10:53 pm tarihinde, Rajul yazmıÅ�: >>> To all Al friends, >>> >>> This is a preliminary observation but I have been able to do cyano on >>> gessoed Al sheets. >>> >>> I added finely sieved Aluminum oxide (Al2O3) to the diluted gesso, >>> and applied multiple coats of it >>> to achieve the desired opacity. Al2O3 killed the super white of the >>> gesso, provided tooth, and did not increase the pH. After drying and >>> lightly sanding coated sheets, I applied 1% agar, and dried them >>> overnight. I still have to improve on the smoothness of the agar coat >>> and will try 0.5%. As expected, agar provided the porosity that aids >>> cyano printing. >>> >>> A cyano mix of 1A + 2B required a 30 min exposure and printed all >>> details. However, on development in diluted vinegar, only the shadows >>> and low mid-tones stayed; all highlights washed out. >>> >>> I will size these plates and see what gum passes will do. >>> >>> Details of the process will follow once I am able to confirm my >>> observations. >>> >>> Rajul
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