Archive for February, 2011

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Gesso Panel Part 2: Making Gesso

February 28, 2011

I am about to take an extra batch of rabbit skin glue (1 cup) made to the same ratio for gluing the fabric to the panel that I demonstrated in the previous posting (1 part glue to 11 parts water,) and heat it up again to make some gesso. This glue has been sitting in the fridge overnight and, as I hope you can see here, has formed into a thick gel. I set it on the stovetop burner and slowly heat it up to 130°F, stirring it occasionally. The electric burners on my stove dial go from 0 to 10, and I set them at about 3 to 4 to get them as hot as I need. A good portable hot-plate with temperature controls would keep you out of the kitchen.

This mix of solids is 1¼ cup of gypsum and ¼ cup of titanium white pigment. I slowly sift the solids into the glue a little at a time, stirring it in very slowly. When all the solids have been transferred to the glue, I continue a slow stir until it all becomes a smooth liquid. If you add a teaspoon of alum powder it will help reduce the absorbency of the gesso when it dries on the panel.

You’ll notice that gesso is not nearly as thick as paint or the acrylic “gesso” you may be more familiar with. It’s about the consistency of heavy cream, which is exactly how you want it… almost. The next step I recommend is to refrigerate it for a few more hours. This will cause the glue to gel again and any air trapped inside will be squeezed out, giving you a smoother mixture. You could apply it now if you wanted to, but I think you’ll be happier if you wait.

Next I’ll show the gesso being applied to the panel.

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Gesso Panel Part 1: Gluing Fabric to a Panel

February 27, 2011

A traditional gesso panel is a wonderful surface to paint on. For egg tempera painters it’s ideal, but it also works well for other water-based paints, like casein or gouache, and for oils it’s perfect. There are several decent online suppliers of them, but it’s not difficult to build your own.

Although gesso can be applied directly to a wood panel, it’s often recommended to reinforce it with a piece of fabric first. Here I’m using a 1/8th inch sheet of untempered hardboard and polyester fabric.

This batch of rabbit skin glue is made at a ratio of 1:11, or 2 tablespoons of powder to 1.25 cups of water. I let the powder soak overnight at room temperature in a covered container so no water will evaporate. If your climate is dry and cool you might want stronger glue (slightly less water,) or weaker if it’s hot and humid.

Before using the glue, it has to be heated to about 130°F. I pour the liquid into a large tin can and place it on an oven burner at low heat and monitor the temperature with an immersion thermometer, occasionally stirring the glue and gradually raising the temperature. Close by I have a large glass bowl of hot water. When the glue reaches 130°, I set the can of glue in the bowl of water to keep it hot. A coffee warmer under the glass bowl can also help keep it hot. Keep the temperature around 120° – 130°.

I first apply a coat of glue to the board with overlapping strokes and dry off the brush. I then drag the brush across the coat of glue in a perpendicular angle to how it was applied, wiping off the brush after each stroke to get a good even coating. I let that dry for a few minutes before continuing.

Next, the fabric is soaked in glue by dipping it completely in the can and squeezing off the excess. I square up the fabric to the board and drop it down. With a plastic scraper I press the fabric from the center of the board to the edges to get out any bubbles, and then apply another coat of glue to the top of the fabric. Invariably the fabric tends to come loose at the edges when it dries, but I’m not too concerned about that. I can pull it tight later when I glue the edges to the back. (My appologies for not taking pictures of this part.)

Once the board and fabric have dried for a few minutes, I place it face-down on sheets of wax paper and put some heavy books on top to press it flat for a few more hours of drying time.

The back edges are glued down with an acrylic gel (this is Liquitex Heavy Gel.) I cut notches in the corners before folding it over, and then apply the gel to both the board edge and the fabric, pulling the edges tight on the front. The gel will set in about 15 minutes. To clean up the back I’ll glue down a sheet of paper or mat board, which also helps hold down the fabric.

The next step will be to make some gesso.

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Art Opening: Imagine 2011

February 26, 2011

I had made a recent post a few days back about the Imagine 2011 Art Exhibit that I was participating in, and here are a few photos I snapped of the event.


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The event was entertaining and very well attended. I was grateful to have been able to participate. Mnay thanks to the Round Rock Area Arts Council.

Links to previous posts on the exhibited artwork:
Biking on CR3112
Whitetail at Dusk

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Acrylic Medium Sizing Test For Oil Paint

February 19, 2011

I’ve written a couple of posts in the past regarding tests I’ve made for sizing paper (it applies to canvas also) before painting on it with oils. One article dealt with using shellac and another with hide glue (aka Rabbit skin glue.) Here I would like to mention another option of using acrylic medium as a sizing barrier. My preferred brand is Golden’s GAC100 and that’s what I’ll be demonstrating here. The coats are applied without thinning with water.

On the left you can see a very thin sheet of paper taped down to a sheet of plastic. On one side I’ve placed two coats of GAC100, and on the right is four coats. After this sufficiently dried for about a day, I applied some oil to both sides. On the top is a strip of refined linseed oil by itself. Below that is a strip of Paynes Gray paint by LeFranc, and Cinnabar Green from Sennelier. I chose these two since they happen to be a bit oily as is from the tube and both use safflower oil. You can also see that the 4 coats of medium is more glossy than 2 coats in the picture on the right.

After only a minute or so, I held this paper up to a window and could immediately see that the oil strip on the top of the 2 coat side is already starting to penetrate into the paper (light spots.) I can’t really see any penetration from the paint oil, but that might just be because of the pigment or the amount of oil being used. Even a day later the 4 coat side showed no penetration at all, even from a generous amount of linseed oil.

The conclusion I gain from this test is to use at least 4 coats of acrylic medium as a proper sizing layer. If you only want the sizing barrier itself, then use 4 coats of that, or you could use 2 coats followed by 2 primer coats of an acrylic “gesso.” Golden specifically recommends their GAC100 as the best medium to use for sizing instead of other acrylic mediums which don’t prevent the oil penetration as well. In addition they also mention protecting against“surface induced discoloration” that might occur from the substrate itself to damage or stain the paint surface. 4 coats of primer alone would protect against oil penetration but not S.I.D.

These sizing coats work fine but are a bit slick for the first layer of oil paint. What I’ve done to remedy that is apply a thin coat of oil paint first of whatever color I wish, even white. I’d suggest using a linseed oil base paint for that layer instead of safflower or poppy since it’s a stronger oil. If you use a primer then that won’t be necessary. One tip to note is that an acrylic primer has a grittiness that can be brutal on brushes, so using 4 coats of sizing instead will avoid that problem.

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Imagine 2011 Art Exhibit

February 18, 2011

This morning I dropped off two recent paintings for an upcoming exhibit entitled “Imagine 2011.”

The opening event will be held at the Texas State University campus main building in Round Rock, TX next Friday evening. The exhibit will continue from Feb 28 – May 18. Please stop by if you are in the Austin area at that time. I’ll try to take some photos at the opening and hope to see you there.

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Cutting Down a Large Art Frame

February 14, 2011

I have this painting to deliver to a show this weekend. Instead of building a new frame from scratch, I decided to just take a larger frame I had on hand and cut it down to a smaller size to save time.

Artwork face-down in large frame


Two L-Shaped pieces


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This required cutting the frame into two “L” shapes and cutting the sides to fit the artwork. The concern here is that this was a finished frame, so the angled cuts had to be as smooth as possible; otherwise, I’d have to sand it down and refinish it, which would waste time. I used a table-saw to cut the angles. The art is 16×17”, and this original frame opening is 20×24.”

Smaller assembled frame

Chip-out: this is what happens when a saw blade leaves the wood and causes small pieces of wood to break off. The problem can be reduced by placing a piece of scrap wood against the opposite side of the wood as it’s being cut. In this case, however, the wood is irregularly shaped and beveled, so the best thing to do is cut the angles face-up so that the blade exits the back of the frame piece. Also, when using a table-saw, slow down as the blade exits and push the wood as straight as possible. Mitre-saws tend to cut smoother angles, but still have chip-out problems, and are a pain to use on hard woods like this.

To be sure the frame you’re cutting down is large enough, the outer edges of the smaller size should fit inside the opening of the large frame. In other words, the final frame size here is 19×19.5″ which is smaller than the original 20×24″ opening.

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Ten Tubas Painting Done

February 9, 2011

I’ve finally gotten this oil painting covered. I need to still make a few touch-ups, but it’s done for the most part. The light in the photo here is catching on some wet oil of the tubas causing it to look less smoothly blended that actually it is. I’ll make a better scan later. It’s 18×24″ on Multimedia Artboard paper.

Oil Paint Palette


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On the right is the palette of colors I’ve used for this painting, for those who may be curious. That’s a 12″ pizza pan covered with a sheet of “Press-N-Seal” wrap. I slip it into a trash bag when not in use to slow the drying time.
In clockwise order:
1> Titanium White, 2> Cadmium Yellow Medium, 3> Jaune Brilliant Hue, 4> Cadmium Yellow Deep, 5> Alizarin Crimson Hue, 6> Burnt Sienna, 7> Raw Sienna, 8> Yellow Ochre, 9> Cerulean Blue, 10> Phthalo Blue, 11> French Ultramarine, 12> Ivory Black, 13> monochrome gray #1, 14> warm gray

#3 is actually PR188, PY3, and PW6 (Holbein)
#5 is PR206 Quinacridone Pyrrole (Winsor Newton)
#13 is PY42, PBk9, and PW6 (Holbein)
#14 is PY42, PBk9 (Lukas)

All of these happen to be water-miscible oils, by the way, mostly Holbein “Aqua DUO.”