Category Archives: acrylic

in search of the perfect panel

First layer of acrylic gesso on A4 aluminium composite panels.

I had been meaning to experiment with using aluminium composite as a support for some time as it has many useful properties:

  • It doesn’t warp much, even at fairly large sizes (up to at least a metre).
  • Takes up much less space than stretched canvas.
  • Doesn’t rot, split, degrade or otherwise fall apart (so I’m told).
  • Provides a solid surface (which I prefer) compared to the bounciness of stretched canvas.

A friend who works in a sign shop gave me an offcut to experiment with. This is 3mm aluminium composite (a sandwich of two thin sheets of aluminium with a polyethylene or polyurethane core). Some kind of polycarbonate surface is baked on at the factory and can come in a range of colours. It’s this surface rather than the aluminium itself which the painting ground will adhere to. Painting on bare aluminium can apparently lead to adhesion problems due to aluminium forming a thin (and crumbly) layer of oxide on its surface.

Preparation

I basically followed the instructions given by Kate Stone in her very useful post More Apocalypse-Surviving Panels which gives all the details about how to prepare these panels. I suggest you go there if you need step-by-step instructions. I went with the ‘acrylic dispersion ground’ option as I’m used to painting on acrylic ground and it seems to be the simplest method.

So the trick is to lightly abrade the coloured surface enough for a layer of acrylic gesso to form a mechanical bond. I used a medium grit sandpaper to create an even scuffing of the surface, enough to take the shine off the surface but not enough to wear through to the bare aluminium. I did try using a small electric sander but found it created hot-spots of bare aluminium, so doing it by hand is the way to go.

After sanding the surface and smoothing down any sharp edges, clean the surface with rubbing alcohol (I used a bit of Gamsol) to remove the dust and grease. Then build up thin layers of acrylic gesso using a house-painting brush. Four layers seems to give complete coverage (see the right-hand section of the test panel in the photo). Allow each layer to dry before applying the next and alternate the direction of the brush strokes for each layer. Many thin layers will be mechanically stronger than fewer thicker ones. Add a little water to the final layer for a super-smooth surface if desired, but I prefer a surface with a little more tooth provided by the ridges from the application brush.

Testing on an offcut of aluminium composite. Left: Canvas sheet attached with acrylic gesso; Middle: gesso over a base of GAC100; Right: four layers of acrylic gesso.

I also experimented with attaching a sheet of loose canvas to the panel using either PVA glue or GAC100 (a type of acrylic used for extending acrylic paint and for sealing surfaces). I didn’t find either was a particularly good adhesive in my limited experiments.

Compared to the other two, the best adhesive by far was, once again, acrylic gesso. I sanded and cleaned the panel surface as before, and added one thin layer of acrylic gesso which I allowed to dry. The second layer of gesso was a bit thicker as some of it would need to soak in to the weave of the canvas. After smoothing out the canvas with a brayer to remove any wrinkles or air bubbles, I put a layer of plastic wrap from some old packaging on top, then weighed the whole thing down with a flat board and anything heavy I could find.

There is one problem at this stage, which is that the wet acrylic gesso is effectively sandwiched in an airtight layer between the non-porous panel and the plastic protective sheet on top, making it slow to dry. I conducted these tests in a damp midwinter, so dryer, warmer conditions might help. Once or twice I would remove the weights and plastic for half an hour to let the surface breathe before weighing down again.

It seemed to work well. The canvas surface was very even. As a test I peeled back the canvas from the panel and, although it wasn’t welded on, it required a fair amount of pull to remove it, and it peeled back evenly with no bubbles or weak points, suggesting a good bond.

Canvas sheet adhesion test.

Panel abuse with screwdriver and palette knife.

I then attacked the plain gesso surface with a screwdriver. I gouged in a crosshatch of lines a few millimetres apart then stuck on some adhesive tape as firmly as possible before ripping it off. Next, I scraped away at the surface with some force using the edge of a metal palette knife. The results of all this abuse can be seen in the photo. The gouged squares did lose some of the paint from the corners where I repeated scraped at them, but this was limited to the corners where the screwdriver had already broken the surface right down to the aluminium. The whole square didn’t come away and nothing suggested that this was a weak or flaky surface.

So based on my limited testing, either a plain acrylic gesso surface or canvas glued to the panel with acrylic gesso will provide a solid ground for oil painting.

Suppliers

Aluminium composite comes under many trade names (one of the original manufacturers sells it as Dibond). Many brands are cheaper Chinese imports and I’ve heard they can vary in the thickness of the aluminium layers and in the material used in the central core. It’s not always clear exactly which brand you’re buying, and some suppliers advertise as Dibond but say they may substitute for an equivalent brand. For our purposes, we just need a panel that won’t warp or dent too easily.

Some people buy large panels and cut them to size using a table saw, or even cut the panel with a craft knife and some determination. (See Amanda Teicher’s video on cutting panels by hand, which contains useful advice on preparing Dibond in general).

I shopped online for a supplier who would cut panels to any size. The single-sided panels are much cheaper (the reverse side is bare aluminium) but only come in white; a coloured surface would make it easier to ensure an even coverage of gesso. After including delivery costs and VAT, it worked out at roughly £1.70 for an A4 panel and £3.40 for A3. By comparison, the cheapest uncradled gessoboard found online costs around £5 for a 20 x 30 cm panel (roughly equivalent to A4 size) and around £9 for 30 x 40 cm (roughly A3). Of course, there’s still the time and effort needed to prepare the aluminium panels and the cost of a tub of acrylic gesso, but it’s certainly affordable.

On delivery, I found that the aluminium sheets in the composite sandwich were slightly thinner than the sample I had been working with. It felt slightly less rigid but was still almost free of any warp at A2 size (420 x 594 mm), and being non-porous there is less concern about the effects of primers or water-based grounds causing warping. So no need for sealing, or priming both sides, or bracing, which might be necessary for wood-based supports.

And there’s something to be said for preparing your own panels. Before you’ve even laid down the first brush stroke, you’ve invested some time, effort and care into creating this surface.

But what’s it like to paint on? It’s too early to say at the moment, but first impressions are good. I created this wipe-out underpainting using only burnt umber oil paint straight from the tube with no solvents. The paint could be easily faded back with kitchen paper, and the slightly toothy surface took the paint evenly from the brush.

To be continued…

 

off the grid

I wanted to practice laying down oil paint in smooth, even blends, like in those classic pictures of old with their ceramic finish and no visible brush strokes. Bouguereau could do it, so why couldn’t I?

To practice this, I decided to do a straightforward copy in oils of a photo by Jérôme Bonnet of Loulou Robert. I liked the lighting and the classical pose. In the rush to get painting, I botched the initial lay-in, and after a number of failed attempts I decided to bypass the whole drawing phase and copy the photo directly using a grid. The grid was drawn on Bristol illustration board and a matching grid was overlaid on the on-screen photo reference. The tight grid ensured that the freehand pencil drawing would never stray too far. It was a shortcut to get to the fun part of the painting. I would worry about becoming a decent draughtsman some other time.

I’d read that James Gurney covers his initial drawings on illustration board with a layer of acrylic medium to seal the drawing and provide a base for oil paint. So I painted over the illustration board with a thin layer of acrylic gloss glazing medium (which was all I had to hand). The thin 220 gsm illustration board warped as it absorbed the water from the acrylic medium, despite being taped down. It did flatten back down later, and the result was effectively a plastic-laminated pencil drawing.

As I found out later, acrylic matt medium would have provided more tooth. The gloss surface is very slick and doesn’t grab the first oil paint layer; the brush tends to smear the paint around rather than being drawn evenly from the bristles by the tooth of the surface.

And this experiment brought to an end to any thoughts as to whether drawing a grid is ‘cheating’ or not. The pencil drawing quickly disappears below the first thin layers of paint, the guidelines are gone and you come face to face with the limits of your own ability to draw. I found that hairlines would go up, jawlines would go down, eyebrows would shift around. They were small inaccuracies, but they mounted up, until the face was no longer a recognisable likeness (or in this case, even recognisably female).

Successive layers of paint were easier to paint on than first slick acrylic layer. I used some Galkyd Slow Dry medium to smooth out the blends, but probably overused it as sometimes the paint would bead-up. The hoped-for ceramic finish began to look more like the surface of the moon after the repeated attempts to model forms and match colours.

I ended up printing out the reference photo and trying to copy it sight size. I was aiming for a close match to the original, both in layout and in colour. Of course, this meant that the best this painting would ever be is a replica of a printed photo.

Although this is necessary practice that highlights the many difficulties in handling oil paint, I’ve got to the stage where it feels like I’m trying to patch up a bad job, and I’m not sure the goal of replicating a print-out is worth aiming for. The foundations are wrong, and any improvements to the painting are mainly due to fixing mistakes rather than building up a picture with a process of progression and refinement. So, the picture remains half-finished on the shelf. I’ll take it out from time to time to experiment further or to try something new. But for the moment, I need to rip it up and start again.

 

blank pages

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The blank page can be an intimidating thing, especially when it’s a large blank page of good quality watercolour paper in an expensive A4 Moleskine sketchbook. The solution, of course, is to fill it with exquisite, delicate drawings of your best work. And that is why this sketchbook sat untouched on a shelf for many months… until I decided to strap it to an easel and attack it with large, cheap brushes loaded with acrylic paint.

It turned out to be ideal for these bold experiments: the large size gives some room for manoeuvre, and the thick watercolour paper can take the abuse without buckling.

The top picture is a rather dark version of a portrait of Louis Betts (without his glasses) by William Merritt Chase. The one below is based on a snapshot taken at a wedding. I often use photos for reference, but this somehow feels like it could never look like anything but a painting of a photo, no matter how I handled the paint. There’s something about the crop and angle of the picture which gives it away.

Comparing Louis Bett’s collar with the front of the wedding suit reminds me of a lesson in James Gurney’s book Colour and Light where he demonstrates how black surfaces in light can often appear lighter than white surfaces in shade.

whose statue?

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A statue over the grave of Constance Christian Hardyman (died 1892, age 25) in Smallcombe Cemetery in Bath, at least those are the details on the headstone. A search on the internet reveals that “Constance [Trueman] died in Bath in April 1892 after the birth of the couple’s first child, Constance Christian“, but that doesn’t match up with the headstone. As with many of the crumbling, lichen-covered headstones in that cemetery, who knows who lies below.

This was intended to be a figure study but I wanted to get it fairly accurate, so for the lay-in I drew a grid matching one over the photo. A rough watercolour wash was used to get the main dark shapes (using Ed’s homemade watercolour set, made from a converted mint tin with the half pans attached with magnetic tape).

After that it was trial and error with many layers of acrylic paint. The colour choices were based on the mid-winter frost-covered scene with its purples, russets, blue greys and whites.

I couldn’t settle on the background. I wanted it to be roughly true to the original scene rather than just showing a generic graveyard, but it looks rather contrived and gimmicky despite toning it down with white mixed with glazing medium. I think I should do more straightforward studies before getting too painterly like this, and develop skills in colour mixing, values and composition.

clouds

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Some isolated clouds out to sea, viewed from a Cornish cliff top.

I’d like to say I made this postcard sized oil sketch on the spot as a pochade, but it was based on a series of photos. A quick underpainting of acrylics was overlaid with layers of oil.

The titanium white is the slowest drying of all the oils in this palette and only goes tacky after a few days. This can lead to problems if extra glazing is attempted too soon. I’ve heard that the slower drying walnut oil is sometimes used for whites instead of linseed oil as it is less yellowing, but I don’t know if this is the case with these Holbein Duo Aqua oils.

The finished painting was hard to photograph accurately. Subtle changes in the ambient light makes the colours and contrast look markedly different.

brown paper

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Trying out a Seawhite Kraft sketchbook, which has 40 pages of 175gsm brown ‘Kraft’ card suitable for wet and dry media according to the blurb.

The card is slightly rough but doesn’t have much texture. Despite the spiral binding the pages have a slight warp and don’t lie completely flat even when new, but I find this encourages more experimentation and quick sketches as I’m not daunted by a perfect blank page.

The main reason for trying this sketchbook was to experiment with a toned background. With the midtones already there, the paint mostly adds highlights and shadows. These sketches in acrylic were to practice mixing the right range of values in the various areas of reflected light and cast shadows.

acrylic blending

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A rough sketch copy of a painting by Fred Cuming to experiment with blending colours using acrylic paint.

Instead of using glazing mediums for the background, I used only water. By mixing the colours on the palette with a wet brush, the paint was already fairly thin when I applied it. After covering an area with wet paint, I would straight away clean the brush and re-wet it, then go back over the area to further dilute and stretch the glaze.

When it’s that dilute, the acrylic paint behaves more like gouache in that it doesn’t bind fully to the paper (at least if the paper is still a little wet), so it can be lifted and faded by scrubbing with a wet brush.  I was using cheap hog hair brushes which allow for all sorts of rough treatment without having to worry about damaging the bristles.

The colours I’ve mixed are a little too garish. The original painting, which I copied from a scan of a greetings card, has a much more subtle palette.

head of Venus

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The head of the Venus Callipyge outside the Pantheon in Stourhead, Wiltshire, painted in acrylics from a photo (most photos I take now are composed with a painting in mind).  The ever-forgiving acrylics allow for repeated alterations. Blending of a sort was possible with glazing medium and working quickly with wet paint, but tones could also be built up by a kind of scumbling as the paint dried. There was a surprising amount of colour in the grey stone.

egg shell

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I found this egg shell on a walk in some local woods. It was caught in a patch of light which made it stand out from the surrounding browns, greens and greys. The outside of the shell turned out to be almost exactly the hue of phthalo blue except for a slight green cast from the light coming through the foliage. This gave me a chance to try some acrylic glazing medium mixed with flow improver. After spreading the clear medium over part of the shell, a small amount of dilute grey green paint could be dropped in then spread and blended with a large clean damp brush.

A blackbird’s egg perhaps, or a song thrush. I’ve no idea if the contents escaped or were eaten.

light copy

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An attempt to copy the lighting in Phil Couture’s beautiful painting “Maiko Satohana“, using acrylics in a sketchbook. I went straight in with the paints as this was more about reproducing the lighting than getting accurate proportions (the face is skewed and distorted).

I’d like to know how he made his painting: Did he work from a model or a photograph? How did he decide on the background colours, the composition? It’s always interesting to hear about what is going through an artist’s head as they make these choices.