Thursday, December 3, 2009

17_Graffiti fresco that never was -- into browncoat

Below is a graffiti-style interpretation of the Mayan fresco at Bonampak, in the back stairwell of the Mission Cultural Center for Latino Arts, in San Francisco. I am inspired to do the reverse -- paint graffiti into wet fresco. Unfortunately, this time we did not quite pull it off:

After being impressed by El Mac's spray can portrait at Roosevelt and 5th Street in downtown Phoenix, I wanted to realize a graffiti fresco before I left Tucson. Undoubtedly, the subtleties of El Mac's style would translate well onto a shining limestone panel. Moreover, I cannot resist the grand contradiction -- that of imposing the contemporary, ephemeral, quick graffiti strokes onto one of the most ancient, long-lasting, and dignified surfaces in art history (being the buon fresco ground of Michelangelo).

There are other graff artists that could also fulfill this fresco/graffiti contradiction, and I found one such talent in Tucson. Unfortunately, the circumstances got away from us, and we did not realize the experimental graffiti fresco, planned a couple of days before Thanksgiving. Perhaps it is just as well, as the larger 3 x 3 foot surface that we plastered for him, cracked after drying. We still have to learn a few things about nurturing unblemished fresco surfaces.

Before our unpainted plaster dried completely, Mikee sponged the surface to bring up the sand, and create a rough surface, or browncoat. The idea was to salvage our effort so far, so that weeks later, we could plaster over that browncoat with a thin intonaco plaster, and again attempt to paint a fresco masterpiece on that same panel, now less prone to cracking. Soon enough we hope to update the history of art with a contemporary graffiti fresco.


Airbrush Experiment

Previously, Gonzalo experimented with airbrushing on a sample fresco panel, splattering the pigment, and spraying too closely, "tearing" a hole in the surface. Ultimately, however, the airbrush worked very well, painting in layers, which hardened well onto the surface when the fresco dried. Therefore we were confident that a skilled graffiti artist could work on his own terms into a wet fresco:

Filling the Iwata airbrush with MayaCrom® Blue pigment ground into distilled water. With the exception of a couple of odd pigments, all the colors went through the airbrush just fine:

Nice airbrush compressor:

Gonzalo noticed that the airbrushed pigment went onto the fresco surface thinly -- the same way, he said, as airbrush colors go onto ceramic. Therefore, he could blow some of the blue color off and make the whites of the eyes; as long as he did not hold the airbrush too close and blow a hole in the surface:


Plastering a Large Fresco Panel

Preparing for the larger graffiti fresco, Mikee used a water power saw to cut a 3 x3 foot panel from a Hardibacker cement board:

The cement board panel had to fit into the 3 x 3 foot angle iron frame, which Mikee previously welded. We should have sealed the iron frame with spray enamel, so that it would not rust:

I laid a piece of plastic over the iron frame, and set the cement board inside. Then I poured distilled water over the panel and soaked it for at least 40 minutes. I probably did not soak the board long enough:

The night before I mixed the lime and 30 grit silica sand, 10 scoops of each (and stored in a plastic bag). At first the mix stays very coarse:

However, when I mixed smaller portions on the plastic cutting board, the lime/sand mix became a lot wetter. Probably too wet, as were the previous mixes:

I brought extra trowels -- a rounded trowel, small trowel, and floater, in addition to the rectangular trowel:

We hired Mikee to plaster the fresco for us. He started with the floater:

Unlike with the square trowel, the rounded trowel on the table allowed Mikee to smooth the plastered surface without leaving ridges:

Final smoothing:

Final glistening smooth surface, still too wet to paint on. We probably finished plastering at noon, and at 2 PM, two hours later, the fresco surface was dry enough to airbrush on:

Mikee strived for a 1/4th inch, or at least over 3/16ths of an inch thickness. We figured that the thicker the coating, the less likely it was to crack:

However, the edges were plastered too thin. To my surprise, Mikee said that we did not have enough lime/sand plaster for the job:

The plaster was way too thin at this corner.

Had Mikee dropped the panel into the frame first, he could have plastered up to the edges of the raised frame, and laid down a plaster coat of uniform thickness. However, I worried that the iron frame would rust next to the wet plaster, and that the fresco would draw the rust in from the edges as it dried, discoloring the painting. Had we primed the frame first with spray enamel, that would have kept it from rusting, and we could have plastered the cement panel inside the iron frame:

Bubbles formed, separating the lime plaster from the surface. We tried to pop all the bubbles, and retroweled the surface smooth:

I soaked some burlap cloth and hung it next to the fresco. I probably should have soaked several old coffee sacks and hung them all around the panel as well. The idea is to keep the air moist about the fresco, to make it dry slower:

Nevertheless, the surface started cracking before it was dry enough to paint. I suspect that I did not soak the Hardibacker board long enough, which later might have wicked the water out of the fresco plaster from below. However, the plaster was probably also too wet, so that the excess water evaporated too quickly from above, leaving cracks in its wake. Also, if the sack of tortilla lime, or the "reverse osmosis" water I added to slake that lime, were not clean enough, the impurities might have promoted cracking as well:

Due to circumstances beyond everyone's control, the graffiti artist did not make it. At that point we decided to make a "browncoat" out of the plastered surface. Mikee sponged the surface to bring up the sand, as they do with concrete finishing:

The sandy surface now created some texture, for a future wet lime plaster coat to grab onto:

I carried the panel upstairs, and out of the way, to dry:

I covered the panel in plastic and left it overnight:

I should have leaned the panel against the wall, vertically, to dry evenly. Instead, I laid the wet panel over a smaller table, flat, which probably caused the corners to crack more severely, for one or all of 3 reasons -- the plaster was thinner at the edges to begin with, and dried faster; the edges extended over the edge of the table, more exposed to air than the center, and dried faster; and/or the geometry of the larger 3 x 3 foot panel made the cement board sag, promoting cracking where the board curved near the edges:

More extreme cracking at the corners:

The edges dried too fast, causing the lime plaster to separate from the cement board in some places. We will probably have to peel off the separated lime around those edges, and replaster the exposed areas, to create a sound browncoat. When that dries days later, we can then trowel a thin plaster coat of intonaco onto the browncoat, and proceed to paint a fresco masterpiece:

In the future we will have to follow Frederico Vigil's example, and use the 5 plaster coats method of Lucienne Bloch and Stephen Pope Dimitroff, in order to avoid cracking. We should probably add Portland cement to the lower coats, as recommended by Ilia Anossov, who teaches fresco painting in Los Angeles, at The Fresco School.


Small Fresco Color Study on Foamboard

Before the night was over, I did a small color study, using the pigments I ground for the graffiti fresco. I quickly spread the lime plaster over a new surface, this foam board which I bought at Home Depot (strangely enough, a bubble still foamed between the lime plaster and the plastic foamboard):

I figured that, unlike the Hardibacker cement board, the Easyboard foamboard would not wick the moisture out of the lime plaster, and thus expected that the fresco would not crack:

I quickly painted a loose color study with Chinese brushes, which I enjoyed doing:

I did not store the fresco in a plastic box to keep it moist, opting to let it air dry overnight. Sure enough, the fresco on foamboard developed cracks, but the cracks might have been worse on a dry Hardibacker cement board. Perhaps if I had sealed the surface first, with a Golden acrylic gesso, I could have avoided the cracks:

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