NaMoPaiMo – How I got to this point

Underglaze9

In the last post, I talked a little bit about the Animal Artistry Hackney shown in the inset picture. I want to use him to illustrate how lighter underglazes “sink” under darker ones, and how that can be used to advantage for certain kinds of dapples. But first let me explain what has been done to him up to the point where he is in that picture.

Like a lot of bone china models, he has a base which can serve as a safe hand hold. Remember that raw underglaze on bisque is too delicate to touch. If the Hackney was cast in earthenware, the underglaze would still be easy to scuff after it was fired, but on a bone china horse fired underglaze is much more durable. But since the green underglaze is really stable under the glaze—it doesn’t fade after multiple fires—my default is to completely finish to base before working on the horse. The picture above shows a row of bone chinas with their glazed bases. That gives me an impervious handle to hold while I work, and also protects the base from overspray since it can now be wiped off. (That is another constraint of underglazing: it is almost impossible to completely remove raw underglaze from anything other than bare bone china.)

Once the base is glossed, I am limited to translucent (“easy stroke”) colors. Opaque colors are supposed to be brought up to Cone 04 (the “bisque fire”), and the gloss glaze is limited to the lower temperature Cone 06 (the “glaze fire”). That’s not a problem for this project, since the translucent colors are more suited to dappling anyway.

Here is what has been done up to date.

Step 1. Base, mane and tail
With each firing, I want to get as many things colored as I can within the limits of my handholds and protection from overspray. So with the Hackney I sprayed the mane and tail black and wiped away the excess. Bone china has the advantage that raw underglaze can be removed with a damp brush. Earthenware, which is more porous, has to be masked because using the damp brush could leave a stain. Holding the horse by the barrel, I added the green of the base and wiped the overspray from the lower legs. That was bisque fired (04), and then the glaze was added to the base and the horse was glaze fired (06).

Step 2. Hooves and pinking
I spray the basic shell coloring on the hooves and pink the face and between the legs. It won’t matter if I have pinked parts of the muzzle that will be dark, since the colors used for bay are darker and will cover the pink. (I am likely going to have to “refresh” the pink towards the end anyway, since it tends to fade.) The glossed base makes it easy to wipe away overspray. This gets fired.

Step 3. The dappled ‘underpainting’
This first pass at the dappling establishes the pattern, so it is much like an underpainting. The Collier in the inset photo is at this stage of the process. For this step, I would have masked the Hackney much like you see in the photo above, with the white parts in that image covered with masking tape. My preferred masking material for bone china is tinted plastic wrap, but more specific areas require either liquid latex or low-tack masking tape. Masking tape works better with bone china. Once he is masked, I give a light spray of dark brown – just enough to tint the bisque. The masking material is then removed and an eraser is used to clean up the edges of the pattern and create the dapples. I also add the first layer of hoof shading (painted by hand) is done at this point, too. The horse is fired at Cone 06 again.

Steps 4-7. Layers of dappling
The next four firings involve the gradual building up of the dappling and body shading. This is done by spraying and erasing. Once I reach the point where I need to some portion of my work “set”, I fire it. Depending on how dark the dappling needs to be, this can take two to six steps. The details on the hooves are being done at this time, too, because I find gradual layers give the best results for them.

Step 8. Final details and glossing the pattern
This step brings us to the horse as he appears in the inset photo. His facial details were added along with the final shading spray of his body. Gloss was added to his white pattern to make the clean-up in the next steps easier.

That brings us up to the present with the Hackney. I’ll post tomorrow about the next steps with photos instead of so much text! But in the meantime, I’ll close by pointing out that the horse pictured has had eight firings, and has two or three more. As you can see reading through those steps, logistics is a big thing in underglazing. When I first started, I would write out step-by-step plans for each project. After almost 20 years, it is pretty much second nature, but I do recommend that new ceramic artists work their approach out, start to finish, ahead of time.

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NaMoPaiMo – How Underglaze Works

Underglaze1

For someone used to painting with acrylics, the switch to ceramic underglazing requires a pretty significant change in approach. The techniques used are likely familiar, especially to someone who already uses an airbrush, but in almost every respect the materials behave differently.

I will be talking in a lot more detail about this once I start posting in-progress pictures, but I do want to set out some big picture ideas so those details make more sense.

Two kinds of “bodies”
To do what I do, I need a bare bisque ceramic. That is, a ceramic model that has been fired but has not had any form of glaze applied. For my purposes, there are two different kinds of bisques: earthenware and bone china. The Animal Artistry Hackney in the picture above was a bone china bisque. The Pour Horse Collier in front of him was cast in earthenware. I can glaze either type, but approaches that work with one don’t necessarily work with the other.

Two kinds of “paint”
Underglazes come it two types: opaque “cover coats” and translucent “easy strokes”. What makes the cover coats opaque is their clay content, and that makes them behave differently than the translucent colors. It also means they require a slightly higher firing temperature than the translucent colors. Which type gets used depends on what needs to be done. For instance, the thicker cover coats work well with scraffito (where they give a crisp edge for a white pattern) but not nearly as well as erasing (where they tend to “pile” instead of giving a soft edge to a dapple). And to make things even more interesting, the individual colors within these two types vary in their properties. There are, for instance, cover coat colors that cannot be etched (Darkest Brown) and translucent colors that are remarkably opaque (Black) when applied.

Two kiln settings
Most underglazing uses two different kiln settings – bisque (Cone 04) and glaze (Cone 06). The bisque firing is the higher temperature. Think of the zero in cone numbers as “negative”, so -6 is lower than -4. Opaque colors require that hotter fire to mature, but once there is glaze anywhere on the model it can only fire at the cooler setting. (Ceramic artists who work with overglazes are firing at much cooler temperatures.)

You are not just mixing pigments
Unlike traditional cold painting, color in fired ceramics is not just about pigment. Instead, colors are achieved by chemical reactions. For instance, iron is used to get red tones, but it requires oxygen to develop. For that reason, many smaller kilns with fewer peep holes give more muted red tones than larger kilns. It is also why the first thing an underglaze artist will tell someone is to avoid any color with the word “cobalt” in the name, because it will tint everything green. Not just that area or that model, but the entire load in the kiln. The “chemistry” aspect is part of what makes underglazing more than a little unpredictable, which can be unnerving when you consider that bisque bodies are difficult for most artists to obtain.

What you see is not what you get
Because the final color is based in chemistry, the material you are painting might not look anything like it should. Companies that manufacture underglazes tint them to approximate their final color, but it is really just an approximation and some colors are closer than others. If you do a lot of underglazing, your eyes develop the ability to “translate”, but it takes a while. Also, those colors with a clay content then to be chalky and give the appearance of being opaque long before they actually are. This means that beyond the first couple of coats, you are adding your shading blind, using only your memory of which areas you hit with more color.

What you get may not stay there
Some colors are less stable when fired than others. This is particularly true of reds or colors with a red content, like the “pinking” on a nose. For that reason these colors usually get added during the last fire.

No touching!
And finally we get to the really difficult part: you cannot touch where you have painted. Raw underglaze is little more than a surface of powder. If you touch it, part of it will come off. Even worse, remember that thing about how the cover coat colors look opaque before they are opaque? That means that if you mar the finish you may not see it until later, after the horse has been glazed. Underglaze that has been fired is only slightly more durable. A huge part of underglazing is planning how you intend to hold the horse, and how you plan to protect what you have already painted.

So to summarize, you will be navigating which type of colors to use, and when those will be fired and at what temperature, all while figuring out how to hold a fragile model without touching any of your work. But it isn’t all hard. I’ll end with one thing that is so much easier about ceramic work, and a strange quirk you can use to your advantage.

Never worry about white again
If you paint appaloosas or pintos, or even just a horse with flashy white markings, you know how much effort goes into creating a smooth, opaque white. With ceramic underglazing, white is the default. If you don’t do anything, you get opaque white. In the case of earthenware, it is even a very realistic warm white. White areas are also your best chance for a good no-muss handhold. If you are going to try your first underglaze project, something with broad areas of white that cover safe handholds—tobianos and large snowcap blankets, for example—is probably your best bet.

Underglaze4
Here I have begun to add the paler colors that will sink under the darker shading. The chalky tan will disappear under the black mane, but will be visible as a golden tan at the lightest part of the poll.

That quirky thing
Underglaze painting is done light-to-dark. This is not optional. At most, a really opaque color may “muddy” a darker one, but even that is hit and miss. For the most part, lighter colors just sink down under darker ones. And that “sinking” is something underglaze artists have learned to use to their advantage.

See those horses at the top of this post? They are both dapple bays – or will be. In both cases, the dark shading and dappling has been done first. The Hackney is dark dappled bay, and the Collier is a mealy bay with transitional dapples on the barrel. The Collier is early in the process, with just the hint of the dappling pattern set in pale gold. The next few steps for him will be deeper red-brown tones where the dapples fade into the darker top line. The Hackney has all of his dappling set and is ready for the final step, which is adding the red-gold and gold under the dappling. That will be added over the top, and he’s going to look sickly yellow-green for a while, but those colors are going to sink down under all the dark details you see now. When it is done, he should look like a deeper, redder version of the color you see on the horse in the masthead of this blog.

I’ll pick up tomorrow with photos of that, since that is today’s work. I’ll also give a more detailed explanation of what has been done with him up until now, and what the next steps are. I also have a different horse that we’ll follow start-to-finish, beginning with pattern design.

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