Saturday 18 June 2011

04__Grinding pigments at the Chicken Farm

It was a big thrill to come to San Angelo to grind pigments, because the Chicken Farm Art Center embodies almost everything I have been looking for in an art community.


Roger Allen is the force behind the Chicken Farm, starting the art center in 1971.


While there are painters, stone carvers and other artists working at the complex, the Chicken Farm is known for its colorful ceramics.


Following the color inspiration, I ground my pigments while sitting next to the potters. Fresco pigments are ground in distilled water only -- no binder (the lime plaster locks the pigments into the surface as it dries and cures).


I ground the pigments with a small glass muller (which I had custom made in Tucson the last time we painted fresco). Then I filled pop-top plastic bottles with a thin pallet knife (see lower right in photo).


Heaven is having a deep sink nearby to wash your pigment grinding tools.


We experimented by grinding a larger quantity of MayaCrom® Blue pigment in a new MiniSonic MT4SV Vibratory Rock Tumbler. I added enough distilled water to make a slurry the consistency of milk. However, after tumbling overnight, the mix thickened to a consistency closer to Vaseline. Apparently this pigment absorbs a lot of water. Therefore I added more distilled water, and let the mix tumble for another day, and the final blend was plenty smooth to paint with.


Other artists have used traditional rock tumblers to grind pigments for fresco. Therefore we also used a regular tumbler to mix MayaCrom® Violet pigment with distilled water. That afternoon we discovered that the contents froze up in the barrel, thickening to a paste as dense as Vaseline, that would not tumble. Therefore we added more water, tumbled overnight, and again made a mix that was fluid enough to paint with.


Tumblers in action. A conventional rock tumbler in front of the new vibratory rock tumbler.


I poured the ground pigments into a plastic Coke bottle.


The MayaCrom® Violet pigment came out foamy when we opened the canister.


Washing the ceramic media in an old milk funnel with a stainless steel screen attached to the bottom.


After 3 days, I had ground all my pigments. Most of the colors were from earth pigments (many from Sinopia), and ground easily into a mud, though some were more sandy. The MayaCrom® pigments, of course, absorbed a lot of water. A single pigment from Williamsburg was particularly hard to grind, as it resisted the water. This Indian Yellow pigment was certainly not made from cow urine, but probably from a chemical dye that colored aluminum hydrate particles. Since most frescoes are painted with the duller earth colors, some traditional fresco painters may not have suffered the nosebleed of grinding the newer, brighter -- but hydrophobic -- synthetic pigments, like this Indian Yellow.


I made a fresco color chart with my newly ground pigments (colors listed from top left to right, in below photo):

1) MayaCrom® Blue 1000 2) MayaCrom® Violet 1000 3) Sennelier Primary Red 686, Quinacridone Violet, PV19 4) Gamblin Mars Orange, Hydrated Iron Oxide, PY42 5) Williamsburg Pozzuloui Earth 6) Williamsburg Italian Pink 7) Sinopia Raw Sienna Yellow from Italy, K40400 8) Sinopia Fawn Ochre Light from Germany, K40241 9) Sinopia Yellow Ochre Avana, Greenish from France, K40200 10) Sinopia Raw Sienna from Badia, Dolomites, Italy, K40404 11) Sinopia Amber Yellow, Dark Yellow from Germany, K40280 12) Sinopia Verona Yellow, Natural Iron Oxide from Italy, K40301 13) Sinopia Gold Ocher, Pale Cool Hue, from Karparthia, Poland, K40194 14) Lukas Gold Ochre 2423, Yellow Earth Pigment, PY 43/77492 15) Williamsburg Yellow Ochre 16) Williamsburg Naples Yellow Italian 17) Williamsburg Indian Yellow 18) Sinopia Slate Grey, Neutral Grey (Davy's Grey) K40930


"Grinding" is sort of a misnomer. Rather than break the pigment down into smaller particles, the object is to surround each pigment particle with water. I assume that the fresco surface better absorbs an individual moist particle, rather than pigment clumps, and thus will lock it into its matrix, when the surface cures and reverts back into limestone. Thus I have read that the longer one "grinds" the pigment, the better.

We tested the pigment adhesion on cured fresco. I made the below fresco color chart a year and a half ago. Roger Allen suggested that we see if any of the pigments would flake off. Only after we poured water on the fresco, could we get a slight bit of the black pigment to rub off. Every other color held tight. So I figured we must be doing something right.



I want to push color as far as I can, which is why I am experimenting with fresco. Pigments should shine truer and brighter on a clean fresco surface, and encourage the viewer to "breath" the image. To this ends, I thought natural pigments might be more seductive, and considered grinding rocks to make my colors. With that notion fresh in my mind, I walked into the Sculpture Resource Center in Tucson last May, and found Trader Chuck grinding colorful rocks.


I would like to thank Trader Chuck giving me 4 plastic jugs of rock dust.


I also experimented with fresco plaster as well. I plastered the below tile a week ago, hoping to use it at the figure drawing session in Lubbock last Saturday (June 11) -- but we did not paint on it. Thus I stored the plastered tile in an airtight Masterson Palette Seal, and left it in my car, driving around in this 105° West Texas weather. To my surprise, the tile was still wet when I opened the airtight plastic box 6 days later. So I painted a color chart on it, experimenting with ceramic color and the rock dust.

It would be so convenient if I could plaster several tiles and store them for at least a week. Then, on a whim, I could ask an unsuspecting artist to do a fresco painting, without involving him in the painful ordeal of the preparation.


I made a color chart on fresco, using the ceramic colors Roger Allen had made by adding industrial stains to clay, and "ball milling," or tumbling, the mix overnight. He uses that color to paint on plates and bowls, which he then fires. The color can change dramatically in the firing process, so that there is a big difference in the fresco color chart and the fired tile samples in the photo below. The ceramic colors are soft and paler than my store bought colors, but nevertheless are very seductive, and have promise in fresco painting.

The 3 colors on the bottom of this fresco color chart are from the rock dust Trader Chuck gave me (I did not paint a sample with the jug filled with Lapis Lazuli rock dust, because the lime would eat it up and fade the color).


I wanted someone at the Chicken Farm to paint a fresco, so I soaked a Hardibacker tile in distilled water for 2 days.


Back in Lubbock, a week and a half ago (June 8), Ken and I mixed lime and sand to make a fresco plaster, and stored it in gallon Ziplock baggies. I left those baggies in my car, and thus the fresco plaster had gotten pretty hot, but it was still wet. I hope that the heat did not affect the plaster.

Plastering the Hardibacker tile, indoors at the Chicken Farm.


The lime slaked through one and a half winters in Tucson. If it froze at any time, the fresco would be no good. However, I do not know how a bad fresco would react. It probably would just crumble, and not set. I believe that the lime is ok, but I am very open with my reservations.

Troweling the lime.


I plastered the tile about 11:30 AM, hoping to paint on it in an hour or two. By 3:30 PM the tile was still too wet to paint on. At first I did cover the tile, but around 2 PM I put it outside, and then moved it below the ceiling fan inside. Eventually, about 4 PM, it dried enough but with small cracks, and so I just used the tile to make a color chart, of all the pigments I ground (color chart pictured before, next to all the bottles).

I know that the plaster was too wet; it is supposed to be dryish but elastic when troweled on. Moreover I soaked the Haridback tile for 2 days, so the surface was probably too wet also.

I used a plastic floater to smooth the plastered tile.



Thus I prepared another tile quickly, using the same fresco plaster, but only soaking the Hardibacker tile for 15 minutes. The panel dried and set up quick enough so that Michelle could paint on it before closing time.


Michelle painting the first strokes.


Midway.

Final fresco.


Small cracks showed up very soon. The fresco cracks when it dries too fast. That is why I soaked the Hardibacker tile for 2 days, trying to prepare the best surface for Michelle. However, apparently I "over-prepared."


We stuck the freshly painted fresco inside a plastic covered box, to make it dry slower. Plus I left some adhesive and an iron welded frame, so that Michelle can hang the fresco like an oil painting, when it dries.


I loved working at the Chicken Farm Art Center. It was very pleasant, functional, and productive. Moreover, I have been looking for a viable artistic community like this -- somewhere beyond the reach of the high rents of the big cities, but close enough to those cultural centers that one could drive in occassionally, on his own terms, to see a museum or relate with other artists. Arcosanti, about an hour above Phoenix, points to that kind of ideal.

I always had a good feeling when I passed through San Angelo. It is a comfortable size, and feels like the Austin I know back in the 70s. I could sense an energy in the air, but only backed into the Chicken Farm recently, when a couple of my friends stayed at the Bed and Breakfast on the grounds before visiting Paint Rock. I cannot believe that I overlooked this art center during the last 4 years when I revolved around Midland, only an hour and a half away. San Angelo is still about 4 hours from Fort Worth or Austin, and thus really more than a day trip away from the Kimbell Art Museum or the music on 6th Street, but seems laid back enough to make one dismiss those few extra hours, when you gotta hit the road.

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