Showing posts with label bisque. Show all posts
Showing posts with label bisque. Show all posts

Tuesday, October 8, 2013

Speaking of Madness...


Brownie—big, medium and petite, or rather resin, earthenware, and porcelain. Besides the shrinkage, also note the different color tones each hasinteresting!

Today we're going to take a bit of a detour from our regularly scheduled programming for a kind of public service announcement about A WHOLE LOT OF AWESOME.

And when I mean "awesome" I don't mean the kind of awesome associated with finding a $100 bill on the ground. Or finally getting that box chock full of brand new art supplies that just showed up on your doorstep. Or even when your husband buys you a pile of mongomonolith Rice Krispie Treats "just cuz." 

No.

I'm talking about the kind of AWESOME that warrants capital letters in italics and bold print. THAT kind of AWESOME.

As you may have surmised from some of my previous posts about my excursions into porceland, my big goal has been working towards a full spectrum of slipcast works along with handbuilt busts, basreliefs and full sculptures in this stuffand last month I hit a major milestone. And not only hit, but hit spot on. I'm still giddy with delight. Can you tell? Is it that obvious? GOOD. Because it's AWESOME.

I kicked up the stakes this year by attempting the first fullbody castings and claybody customs in slipcast porcelain. I actually poured the initial bodiesa Brownie, a Collier and a couple of Limericksat Mudhenge 2012. I chose these pieces because they had thicker legs in relation to their mass, and that's important for reasons we'll get to in a moment. That said, I have to admit they languished for some time in the wet box before I could get to them. Fortunately, this didn't prove to be a problem thanks in large part to vitrification

I started first with the Brownie. I assembled and cleaned him as usual, but left him unchanged since I wanted a baseline with this porcelain. As for the three minis, I tweaked them starting first with the Collier which got just a bit of alteration then finishing with the two Limericks who got the most extreme changes. I wanted a progression to make clearer deductions later. I used all the same techniques one would use with stoneware or earthenware, trusting that vitrification would melt everything together as I learned from the claybodied Reflectives.


This is the brand of porcelain slip I use. Other colors are made, which would be fun to explore.

But I did employ one extra step: burnishing. Slipcast porcelain dries very quickly. Honestly, it's not unusual for me to pour, clean, and bisque fire such a piece within 12 hrs during a hot, dry Idaho summer. That means by the time I get to the final stages of blending and refinement, the clay may be rather dry despite regular spritzing with a water spray bottleand that spells cracks and lifting during the mature fire. It seems that vitrification can only do its magic if it has something to grab onto at that critical moment, and burnishing seems to give the parent clay "fingers" by truly mashing it together with the additions.

Becauseyessometimes this step is needed despite wetting, scoring and slip, especially with large additions. To burnish, I used circular motions with just enough pressure and just a dash of water to mush and squish the two together without destroying things. It's essentially grinding in the edges of the larger added sections, those usually entailing the torso, hindquarter, and neck. You'll also want to do this with the edges of sections that were added to make portions longer, such as lengthening a neck, torso or leg. Any tool with a curved, domed smooth surface will doI used the back of my favorite sculpting tool.

This is the spoonlike shape I mean—the back of this shape is really handy for all sorts of sculpting tasks. That's green vet wrap around the tool on the left to help my grip.

I also tend to burnish the area before I start sculpting in earnest because I want a good bond before I really get to work. Afterwards, I roughly block in the area followed by generalized smoothing (with water and a soft brush) to create a blank slate of sorts. Then I allow it to rest for a bit, just to toughen up and dry out enough to avoid becoming a mushy mess, and then I start my actual sculpting. Nevertheless, a lift or crack can erupt despite it allit's rare but happens sometimesbut it's an easy fix: just add more slip, reburnish, resmooth and proceed as usual. As for delicate bits like legs, ears, tendrils and such, I've been able to burnish them as well, albeit not so aggressively.

Assembling the Brownie, who has a separate mold for his head and front legs, and the start of the long, sad, tedious series of breaks on the Dutch Draft Limerick.

So I motored along like this until a distraction pulled me away and I had to pop them back into the wet box where they waitedand waitedand waited. And. Waited. By the time I'd gotten back to them, to my dismay I found they were bone dry! Thanks to my preoccupation I'd completely forgotten to periodically rewet the plaster inside the wet box that, ohactually made it a wet box. GAH. Such a gross oversight would have been a deal breaker with earthenware or stoneware. Either I'd be forced to make the best of it as they were or throw them into the dump bucket. Alas, reconstituting these clays back into the proper consistency for claybodying just doesn't work very well. That lovely pliability so necessary for the process just disappears when the clay is allowed to dry and, even more, it doesn't offer the same strong bond it would produce when damp. But in the hopes that vitirification would generate a different outcome, I forged ahead and prayed that everything would fuse together despite my startling incompetence


The Collier suffered his share of breaks, too. It got to be ridiculous.

The Brownie went easy as pie. The Collier was easy, too, as was one of the Limericks. The other Limerick, however, was a real trick pony simply because I decided to input some really ambitious changes after he was dry. It was my own fault—I'd sculpted myself into a corner with him. See, I initially beefed him up to make him more like a Dutch Draft (as a study for Himmy). Fine—all great and dandy. But after I came back to him, I was completely convinced that he needed a longer back and forearms to synch better with his new proportions. Okay, that was tricky enough, but as it so happens I accidentally destroyed his already completed head while doing just that, forcing me to sculpt an entirely new one. From scratch.

And when we're talking 1:32 scale in dry greenware porcelain, piecing together a tiny pile of body parts, let alone making new ones, is a really dicey proposition. Not to be daunted though, I made his new head from a puddle of porcelain slip transformed into a consistency more like pug clay. To do this, pour the same slip onto a plaster mold to suck out just enough water to make it malleable like pug clay. Pull it up (be careful to pick out any plaster bits or debris) knead it, and sculpt accordingly. When leatherhard just hollow out those portions that are too thick to dry or fire safely. This is a handy trick for creating bases, new body parts or manes and tails, and I use it often.

But dry clay, and dry porcelain in particular, is really delicate. Being unfired, it's basically just dried dirt held together by the adhesion of its own particles, what we call greenware. Now because any ability to flex is gone, pressures, harmonics, or vibrations beyond its ability to withstand will then result in breaks. And since I'm so darned clumsy, the legs on this particular Limerick were flying off like shrimp at a Benihana. SNEEZE. Boink! HAND SLIP. Bink! KNOCK TABLE. Twink! HICCUP. Doink! 


An inprogress shot of the Dutch Draft Limerick. You can see the repair on that one forearm, too. As you can tell, he got entirely new ears along with his new head. When I wipe something out, apparently I really wipe something out.

All that's fixable, of course, but fixes usher in their own problems all the same. For one, a break usually remains even more delicate an area, and so really precarious repairs should be done last just to hedge your bets that an intact piece will make it into the bisque fire. Or for another, you can do such a good job repairing a break that it actually becomes stronger than its surrounding areas, forcing them to break around the repair. I've found this to be a peculiarity with porcelain, which is exactly how I ended up with a congaline of breaks up each leg on this Limerick, all of which then added weight to that structural column to exacerbate the likelihood of yet another break. It got to a point where I could actually hear circus music in my head. 

Now if he'd been a larger piece, I would have sculpted and cleaned each broken piece perfectly and then reattached it (again, leaving the repair "for last"). But at 1:32 scale, this isn't only a logistical problem, it's a creative problem; the smaller the piece, the more necessary it becomes to sculpt in situ to maintain coherent anatomy and proportion. So after the circus music had played through its many loops, the final toll was at least three separate breaks on each of his tiny legs! It was like operating on butterfly wings. I didn't even dare breathe! Thank goodness Dutch Drafts have thick feathering, that's all I can say. But I was determinedone could even say obsessive—and this wasn't going to stop me. Being bullheaded does have its perks in art though, as it tends to add new troubleshooting skills to one's repertoire. You know what they say about necessity and invention

For example, there's definitely a trick to working through a congaline of breaks. Wet and score your surfaces as usual, but use the least amount of slip necessary to reduce the amount of scraping, i.e. pressure. Then let that leg "rest" after reattachment, to allow the clay to solidify and toughen. Don't let it get too dry though, just "hard damp." Then use a soft brush (I like to use a pointed round or angled flat) to dampen only the immediate area you're working on to clean, sculpt, and refine. This minimizes pressures and helps to mediate weakening the area with oversaturation. Also, don't work on the whole thing or even on sequential portions all at once. Give the leg time to rest between each repaired portion, then when you do come back to it, work on the area opposite where you just finished. This creates selfreinforcing weld points that seem to hold up better.

When you're done, use a soft damp brush to smooth the entire leg, starting with the hoof and moving up to the bodythat is to say you don't want to first soak those areas that will have to withstand the pressures of smoothing. Be painfully light in the touch and take extra care not to saturate. Allow the leg to rest when needed, and remember that any additional smoothing can be done later in the bisque with sandpaper. Now granted, it took some time to fix all the legs in this painstaking way, but it worked! I learned a greater feel for this stuff in the process, too.

Here's another tip: when sculpting in slipcasting porcelain, do your sculpting, especially your details, a little sharper than usual. During vitrification your sculpting will soften a little bit. Think of butter in a warm oven. So those features you want really preciselike eyelids, wrinkles, chestnuts, hoof chips, or hairyou want to make very defined and crisp, so don't blend them too much with your water and brush. Let vitrification do that for you. But any hollows you sculpt, like for muscle groups, the underside of the hooves, or nostril and ear cavities, will remain as they are—they don't "fill" from seepage. You'll get a feel for how this medium behaves the more pieces you create with it, which is where basrelief and medallion work really comes in handy!

Anyway, so here they are in greenware going into their bisque Cone 04 fire


The Brownie.

 The Collier.

One of the Limericks, made into a Cob.

The Dutch Draft Limerick.

All four were bisque fired on their sides because I felt I'd already tempted Fate plenty by this point. Bare clay won't stick to anything in the bisque fire because glaze isn't involved and the temperature doesn't get high enough to cause fusion. I often stack my tiles and ornaments in the bisque fire to really pack Big Al, for instance. The next morning then, I popped open Big Al to find they'd all bisque fired just fine and dandy. And that was great. Really great.

But there was a problem. One big problem actually. And if you know anything about firing full body porcelain sculptures like this, you may have already deduced that one big problem by now. Again it was my seemingly instinctive propensity for distraction and subsequent gross negligence at the root of this big problem to boot. I swear, sometimes I think I'm too incompetent to work in ceramics! 

See, here's the thing: had I not been so fixated on sculpting, as per usual, and actually been thinking about what I was really doing, I would have remembered a vital component to these piecesthe stilts. The blessed stilts! But I hadn't. Of course I hadn't. That would have required thinking ahead and we can't have that now, can we?

To understand why this is a problem, let's backtrack a bit. At vitrification, the porcelain momentarily turns into a jellylike substance as it chemically changes into its glass–like final form. That means any sticky–outy parts (like tendrils, ears, legs, etc.), or slender portions that support weight (like legs or tails) are vulnerable to warping and slumping as gravity pushes downward on the mass of the piece. Clearly then, equine sculptures are a smorgasbord of every conceivable pitfall one could encounter with porcelain in this regard, aren't they? And this problem is more a function of mass than of size, too, which gets back to the reason why I chose sculptures with thicker legs in relation to their bodies. It also explains why there's a threshold mass where porcelain just isn't feasible anymore and a metal like bronze is the better choice.

But getting back to the issue: ceramists have managed this problem through the process of "stilting," of creating a series of supports, like flying buttresses, to shore up vulnerable portions and to support the mass of the piece. For a production piece, stilts would be designed specifically for and alongside the original, and have their own molds that would be poured at the same time in the same slip as the sculpture itself, and they'd be dried at the same rate, too. For this reason there's a comparable amount of clay used in the casting of the piece that's discarded at the backend of the process in the form of fired stilts. Add in the approximate 30% loss rate on top of this, and you may now understand some of the reasons why porcelain (and fine bone china) is so expensive and exclusive.

But for oneofakind pieces like these claybodied guys, I have to make oneofakind stilts for each of them, made from the same pour and allowed to dry right alongside them at the same rate. Or rather I should have. So I was in a real pickle—not only did I already have fired bisque sculptures, but I was also left with a jar of slip from another batch of porcelain. There I was with everything wrong.

But why the same clay? Made the same way? Dried at the same rate? Good questions! Here's why. Due to its chemical composition and its lack of grog, porcelain shrinks quite a bitabout 13%15%. That's a lot. In fact, it's the highest shrink rate of all ceramic clays. This is why porcelain casts fired to maturity are so much smaller than the original sculpture, or casts poured in other clays. Such casts also tend to be much heavier because porcelain is quite dense. 


Look at the shrinkage! A resin Brownie (left), an earthenware Brownie (middle) and the porcelain Brownie (right).

With this in mind, you now have a big clue as to why the stilt problem was a big one. How so? Well, while each batch of porcelain may be mixed according to a recipe, slight differences in chemistry always exist induced by supply, bacterial flora, and circumstances that can slightly change the properties of each batch—or more specifically, slightly change the shrink rate of each batch. How the clay was stored and used by the artist can also add further peculiarities that affect its nature, i.e. its shrink rate. Put all this together and we can think of each pour session of porcelain as unique. And we want those stilts to shrink exactly the same as the sculpture itself; otherwise support will be compromised to either mar or even destroy the piece.

Which is why my woeful oversight concerned me so much. All my hard work, painstaking care, and dogged determination may have all been for naught simply because I'd spaced this one critical component. Trust memy neurons and basal ganglion were in a frenzy assigning blame because I couldn't really leave these pieces as bisque porcelain either. I've found bisque porcelain to be surprisingly fragile. It just doesn't seem to have the gumption of bisque earthenware or even bisque stoneware. It needs to be vitrified. As with all things in life, the only way around it is through it then. I had nothing to lose, right? So I decided to mush on, to see what happened.

Nevermind that I'm totally ignorant in the whole stilting gig, a fact that neither impeded these experiments nor deterred my resolve. As you've probably guessed by now, my modus operandi is to just dive in and learn to swim later—it's reckless, I know, but new ground isn't found by playing it safe. I also must admit that the Universe has been unquestionably generous with my adventures in clay, something I choose to interpret as an open invitation to get crazier. Can do.

Nonetheless, even though I knew what had to be done, I still had no idea how to do it. Having sculpted myself into a proverbial corner, traditional stilting wasn't going to be feasibleI deduced that much. I had to cheat construct a strategic engineering remedy. Gawd, I'm pretty sure Fate is going to catch up with my shenanigans at some point, whip around and chomp me in the hinderuntil that happens though, onto cheating strategizing

After consulting with fellow mudhens, Joanie suggested belly supports rather than actual stilts. They'd bridge my howling deficiency in the logistics of stiltmaking while simultaneously creating a workaround for the compositional disparity between the supports and the sculptures. A basic scoop that supports a belly is far more forgiving than flying buttresses of exact measurements. Brilliant!


Here's the Brownie on his belly support. Note the "prongs" projecting outward from his belly and back between his hindlegs, designed to keep him balanced and upright.

To make these belly supports, I turned porcelain slip into malleable clay in the same way I did for sculpting that Limerick's new head and then went about customshaping little contraptions for each piece. This wasn't a haphazard endeavor, however. Each support had to achieve five nonnegotiable goals:
  • Lift the sculpture off its feet to remove gravity's effect as downward pressure of the body's mass during the critical moment of vitrification to protect the legs from warping. Equine legs should adhere to a very specific set of anatomical and conformational angles to remain viable, so protecting my sculpted legs from warping or misalignments is a priority.
  • Not interfere with the sculpture as both shrink. The support had to steer clear of the hooves, feathers, legs and tail so it couldn't influence the "shrinkage pathways" and potentially cause distortion. It also couldn't interlock with the sculpture. It's amazing just how quickly those legs and body features can create a kind of Chinese Finger Puzzle effect with the support if the ease of removal isn't given equal attention as support. Lastly, the supports also couldn't hook onto or cause drag on any feature sculpted into the torso which could damage the piece. Support wasn't necessarily served by a mirror image. In theory, too, I could make two or three base supports for a particularly complicated piece if these problems warranted that, but I haven't gotten to that point yet.
The Limerick turned into a Cob on his base. Note the sharp right turn on that one buttress. Functionality is the motto here!
  • Maintain support while shrinking. As both the sculpture and support shrink, it's possible that the sculpture's center of gravity will shift to alter its balance. If that happens without accommodation, the sculpture could tip, rollover, or fall right off the supportand even a tip is unwelcome by changing gravity's angle of influence. In line with that idea, each support had to keep the sculpture at a perpendicular angle to maintain the desired angle for the legs. I want those foot bones, cannons, and long bones straight! So while I made the supports snug, they weren't too snug. They had just enough wiggle room, like a comfortable T–shirt. I also made them with the idea of a cupped hand rather than as a flat tabletop, with the rims a snidge higher. As a test, I slightly jiggled a sculpture atop its support to determine how it all balanced—carefully, of course! If the sculpture stayed where it was, I figured it was a suitable base. If it shifted, adjustments were necessary. (Remember, too, that I was making greenware bases for bisque sculpturesideally they'd have been made together. I imagine in the future I'd allow the sculpture to dry so I could lightly make a good belly impression into a fresh clay base. A gentle wiggle and squirm would then help generate the accommodating room necessary.) 
The Dutch Draft on his belly support. You can see what I mean regarding all those goals in these images.
  • Be stable. The base had to be big enough, splayed enough, and have enough weight so if the sculpture shifted or rocked, it would stay put. It had to be the rock. The supports were first formed solid for straightforward shaping, but were later hollowed to minimize the possibility of exploding air bubbles. Not too much though—they had to keep some weight and durability to do their job.
Here are the belly supports on their sides so you can see how they were hollowed out, and their odd shapes.
  • Not stick to the sculpture. Because vitrification causes the porcelain to essentially melt, any bits that touch will actually fuse together, just like glaze. So if the sculptures were simply plopped onto their supports for the mature fire, they'd melt together into a big wad of NOPE. So I coated the entirely of each support with three coats of kiln wash (except the bottom of each support since I wanted an unfettered surface on the underside, plus my kiln shelves were already kiln washed). The wash was about the consistency of pancake batter and applied with a brush. Nothing fancy, just purely functional. And only the belly support was kiln washed. The bisque sculpture was left bare and pristine. In bated breath I hoped that the kiln wash would act as a barrier, allowing me to simply pop the sculpture off the base when the mature fire was completed.
Getting kiln washed.

Needless to say it was a delicate balancing act to get those belly supports just right. Trickier than I expected, and they certainly took on odd forms, but function was the only name of their game. And thinking about it more, I expect all these issues, especially that of base stability, to become increasingly important as scale increases. Mass is a big issue with porcelain. To be quite honest, I think I skittered by despite my mistakes thanks to the small scale of these pieces as I'm not sure bigger pieces would've been so forgiving. I must pay better attention to the process the bigger I work!


All done and ready to do their jobs! They kinda look like tree stumps, don't they? The one in the upper left has a hole in it where my hollowing cut through, but it proved to be no big deal. Those bare spots are there so I could see the identifying abbreviations for each sculpture, so I knew which bases went with what sculpture.

Another fortunate happenstance was this: I poured the sculptures rather thickly in anticipation of claybodying, and even the Brownie was a thick pour. So not only did these pieces have thicker legs in relation to their mass, but they had thicker body walls, too. I believe this was a boon when it came to the belly supports since these thicker walls could better support the piece's mass without distorting. Plus, an arch is a sturdy architectural structureso hooray for hollow torsos! I must keep all this in mind for future work!

The Collier on his belly support. This one was especially tricky, since it posed the most risk of interlocking with the legs. Thankfully I avoided that with a more "puddled" design.

One complication I couldn't escape, however, was porcelain's memory. I had to make the bases as close to my intention as possible right from the getgo because its memory could reform them back during the final fire, and that could be a problem with balance and stability. So I had to have a pretty good idea of what I had to do before I did it. It's helpful that the brain quickly develops a knack for anticipating how a sculpture might behave in shifting conditions. It catches on pretty quick.


Here they all are on their bases.

As a workaround, too, I found that first making a block, then getting a belly impression, then forming the avoiding cavities and stability features, and then making adjustments seemed to be the best approach. After hollowing them, removing sharp edges and being allowed to dry, they were then bisque fired to Cone 04 to bring them to the same stage as the sculptures. It was after their bisque fire that they were then coated in kiln wash. That is to say I didn't fire the greenware supports, already covered in kiln wash, straight up to Cone 5 with the sculptures.

Still and all, none of these supports are reusable for future pieces. Being specifically custommade is one thing, but being specifically pre–shrunk is another. So they're essentially nothing more than curiosities now. I'm half–tempted to stick them in my garden as fun novelties, or even include them with the piece as a relic of the process. Still cogitating.

In Big Al, ready for the mature Cone 5 fire. Rather than placing the belly supports into Big Al first, then popping each sculpture onto them, instead I secured each piece on their belly support first on a tabletop so I could be sure of their exact balancing, then gently clamped my fingers around the whole kitnkaboodle to pop each onto the kiln shelf. That worked much better to get them just right. 

Another element I had to cogitate was how to fire them. Up until this point I'd used this slip to make bigger basrelief pieces or sturdy boxes, but never before with such tiny pieces, let alone in fullbody compositions. And that was a concern. If this midfire porcelain gets too hot, it turns into a puddle of lava, with bubbling, puckering and general catastrophe all 'round. So I definitely couldn't let that happen, but which could so easily be the case with the delicacy of their tiny bits.

Now the way a clay gets too hot during a fire happens in two ways. First, the actual temperature can be set too hot, which is easily amended by simply firing at a lower temperature. But the other, and more overlooked, way a clay can become too hot is to be fired at its correct Cone for too long. At least I've found that to be the case with midfire porcelain. Indeed, firing this clay isn't just a matter of temperatureit's equally about time. The longer this clay is allowed to "soak," the more intense the result. (This is the basis for "ramping" a fire, but we won't get into that since it doesn't apply here.)

So I definitely didn't want these guys to soak for too long. I knew that Big Al's Cone 5 on Fast was perfect for the larger, thicker porcelain works I previously fed him. But that's a problem, seeI'd already maxed out the time with the Fast setting. So my only other option was to fire at a lower temperature, at Cone 4. I knew that Big Al fired on the hot side, so I anticipated that Cone 4 would suffice with such small pieces. (There's a way to program Big Al to fire at Cone 4.5, but I haven't figured it out yet.) I knew I could always refire hotter or longer if Cone 4 on Fast was too cool for vitrification to take place, but there's no way to fix boiled, bubbled blobs. So through the night, Big Al cooked them at Cone 4 on Fast, and I waited anxiously for the morning.


Here's the Dutch Draft Limerick all spiffy after the mature fire. You can see the amount of shrinkage in the composite image in the upper left. Hooray! Cone 4 on FAST was sufficient to vitrify these tiny fellows!

As you might have surmised already thenit all worked, and it all worked beautifully! Big Al popped out four perfect little porcelain pieces with zero slump, warpage, or distortion, all vitrified and with a lovely, glassy sheen. And heavywow! More still, each popped off his belly support with absolutely no fusion, marring, or interlocking. Success! I'm also happy to report that the customizing and even all those leg breaks melted together so flawlessly, it's as though they never happened, confirming my predictions on what vitrification would and could do for such circumstances. And when it comes to clayand especially to porcelainbeing able to predict anything involving such extremes is a real boon. It tells me that all those claybody Reflectives were impeccable teachers, and also that this slip porcelain was indeed a viable medium for this type of work.

But one thing that did prove to be inescapable was the matter of the glaze. Earthenware and fine bone china are brought up to maturity first for the clay. Earthenware clays generally fire to maturity at Cone 04 while fine bone china mature fires much hotter, anywhere from Cone 210 depending on the recipe. Once they've been mature fired, however, they're "in the clear" so to speak, and then the glazes are fired on afterwards and at lower temperatures. This means they're available for more glazing options such as underglazing, overglazing, and even art glazes.

Not so for porcelain. Porcelain and its glaze must come up to maturity together or the glaze will flake off. This means that underglazing isn't available for porcelain because the final "sealing" clear glaze cannot happen. It also means that applying a midfire or highfire clear glaze to the bisque porcelain for chinapainting, or even art glaze, isn't an option because how could that happen with stilts, let alone belly supports? Not only would that risk fusing the support to the body, but a lip or ridge would remain where the glaze met the bare porcelain, giving the impression of a massive ringworm infestation. 

It's conceivable that belly supports with little prongs could be made to minimize the surface area that touched the sculpture, with glaze applied everywhere except those areas that contacted the touch–points. But not only wasn't I that motivated (or even that skilled), but I believed that was asking for way too much to go wrong. For one, what if the sculpture shifted during the shrinking, moving the prongs out of the bare areas? What if the prongs couldn't dissipate the weight of the sculpture well enough and slumped or collapsed? What if the belly wall puckered or blew inward under the weight focused on those touchpoints? 

Ultimately, I decided that I'd rather have a pristine unglazed sculpture than a marred glazed one. And that decision was the right one for me as preserving the integrity of the sculpture will always be my first priority. And regardless, I figured I could at least coldpaint the pieces if push came to shove. But even so, it's obvious how much I adore the look of bare bisque porcelain anyway, based on my claybodied Reflective work. To tell the truth, I plan to leave much of my future handbuilt porcelain work plain bisque precisely for that reason. I fundamentally consider myself a sculptor more than anything else and, in my opinion, bisque porcelain is an ideal medium for showcasing a sculpture entirely on its own terms.

In spite of all that though, I later learned that I could still apply fired pigment directly onto the bare porcelain if it contained enough flux, and if it wasn't applied too thickly. Swooping into my rescue then was a fellow mudhen who just happened to find a source for exactly that kind of pigment! Thank you a million bajillion times Jen! And thank you Karen for bringing this sacred stuff to Mudhenge 2013 so we could see it in action! I cannot wait to go shopping. I'll be like a kid in a candy store!

Along with all the highfives, hoopla, and highlights, however, there's always a price to be paid, isn't there? A tribute to the ceramic powers that be for such good graces. And remember that Fate thing coming back to bite me in the hinder? Well, it took a goodly bite. CHOMP. For the unprecedented generosity such powers saw fit to bestow on me for these experiments, they demanded a sacrifice of equal measureand they got it. They took the Cob. As I was staging his photograph, I clumsily bumped the table and he leapt onto the concrete floor, shattering into seven perfect pieces at seven perfectly clean breaks.


The Cob, after he was sacrificed.

But, heyseven is one of my favorite numbers! And perhaps this was the Universe's way of forcing me to keep him for myself. I'd originally decided to do just that as he seriously grew on me during his creation, but life happens from time to time, forcing me to sell individuals from my own personal collection who are hard to let go. He's stayin' with me though! After some glue (and eventually a new ear because I haven't found it yet) I've pieced him back together, and he's my new studio mascot, christened "Eggar" in reference to Humpty Dumpty. Admittedly, too, I inadvertently sculpted his head a teensy bit too thin in my enthusiasm (as seen from the front). I decided against amending that odd aspect, however, because I already liked his head exactly as it was from the sides so darned much anyway. So either which way, it's a happy ending.

It's been a couple of weeks since I pulled this lot out of Big Al—this post being delayed by Mudhenge 2013 (another post coming on that, stay tuned)and yet I'm still tickled pink! The potential for my sculptures to also be offered in porcelain as castings, claybodies, and handbuilt works is like Christmas, New Years, my Anniversary, my birthday and winning the lottery all wrapped up into one ecstatic, blissful package.


The Collier after the mature fire.

Add into that the new Ferro Sunshine options for pigment, and lemme tell ya—I've been pinching myself a lot lately! See, I told youa whole lotta AWESOME! In the meantime, this calls for kicking the madness up another notch, don't you? Onto bigger sculpturesas my orbs meander on over to those PixieDafydd and Stormwatch molds

"Far away there in the sunshine are my highest aspirations. I may not reach them, but I can look up and see their beauty, believe in them, and try to follow where they lead." ~ Louisa May Alcott

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Wednesday, October 10, 2012

I ReDo that Taboo with Voodoo


Maury is so happy! He's done more firing in the last few days than both he and Big Al have done in the last few years combined!

As mentioned in the previous post, that Taboo came out of his final glaze fire with his pinking completely cooked out. This is common with reds (and to a lesser degree oranges and yellows), which tend to fade during the fire, especially if insufficient fresh air is supplied. This is why we like to keep at least half of our peep holes open (or all of them) if we have red–laden pieces baking away. Even so, reds are notoriously unstable and so pinking should be applied rather liberally to have any hope of adequate intensity after the fire. I've yet to figure out just how much that is though, and somehow manage to screw up on the side of the spectrum of "not enough" with hairpulling regularity. Such was the case with that Taboo.

Here he is, right out of the final glaze fire with all his carefully shaded pinking gone gone gone. BAH!

Creating art—especially in the learning stages—isn't all joy and rainbows and brilliant strokes of genius. There's actually quite a bit of bumbling around, accidents (both good and bad), total surprises (again, both good and bad), lots of pondering, and at times frustration and disappointment. It's messy. And sometimes you get mad. Indeed, sometimes you need to get mad since it can be the battering ram needed to bust down barriers to advancement, or said another way, to drown out that little voice of failure. Crafting art can be like boot camp at times it seems, and if that was the case here then that Taboo was the target I just couldn't hit. I needed a howitzer.

That's to say I needed a bigger toolbox. Cue in overglazes. I'd been wanting to play with this stuff for some time, using the nifty starter kit Lynn provided at the last Mudhenge. But it wasn't until Karen's handpainting demo that things really clicked into place for me because the techniques she demonstrated were similar to my ol' coldpainting methods. So with that Taboo defiantly staring me in the face, fatally flawed and excruciatingly irritating, there's no time like the present, is there? What do they say about necessity and invention? How does that saying go about getting mad and getting even? All clichés aside, that provocation really got the gears going, greased by my inherent stubbornness.

So with dubious abilities and blind enthusiasm, I just dove in, using pigments from the kits both Lynn and Karen so generously provided. Totally reckless. That shouldn't come as a surprise, though. As you may know by now, I'm not one to cautiously test the creative waters with a toe, properly outfitted with the appropriate gear and fully trained, to then carefully wade into the waters with one eye affixed on the shore. Nope. I get a running start and cannonball! BANZAI! *Splash* I'm lucky if I remember to take off my shoes.

Some of the materials enlisted to fix this puppy. That's a plastic palette and in the tins and tall glass bottles are the dry overglaze pigments. There are various mediums you can use to emulsify the pigmentsdepending on what you want to achieve and how you prefer the consistencybut here I'm using the glycerine Lynn provided in her kit (you can find it in the cakemaking or soapmaking isles in an arts and crafts store like Michaels). You mix the pigments directly into the medium (in this case glycerine) to the consistency you want. In my case, I aimed for the consistency of heavy cream and applied it with brushes.

To distill all that messy, "on the fly" learning into one coherent impression then: it was true love even before my bristles touched that shiny surface! Here was a fired media that combined with underglaze to produce results that not only matched my aims, but did so in a way more agreeable to my madnessinduced way of creating. So let me share some interesting things I discovered along the way so farand expect more as I wallow deeper in this marriage as I'm sure plenty more revelations are waiting! 

So first off, let's discuss some of the pigments I was using, those provided by Lynn and Karen

These are the colors I used on this guy. Lots of horsey colors are possible even with this limited palette, and the options are infinite with the addition of new pigments. Really, I suspect I'll be duplicating the massive coldpaint collection I have with overglaze pigments!

So here are some of the loosey goosey aspects of overglaze pigments:
  • You can utilize complementary colors to deepen, darken or enrich your target color without having to kill it with black. That means you can use blues, purples, greens, violets and such to amplify your palette.
  • Likewise, you can use pure brights to intensify highlights rather than relying on underlying white. So bright reds, oranges, yellows and the like can be used to punch up colors without the "pastel" effect of white.
  • You can custom mix your own colors from the large array of standard colors.
  • You can custom mix the consistency of your overglaze pigments through all the various mediums you can use. For instance, glycerine imparts the feel of oils thinned for glazing, or a thick watercolor feel. Conversely, fat oil creates a thicker, traditional oil paint feel. There's also lavendar oil, clove oil and many more mediums to suit just about anyone's preferences. I even successfully tried honey! 
  • You can use overglaze pigments in their glossy form (as–is), or turn them into a satin finish or further still into a true matte finish with zinc oxide, a matting agent available in powder form. You do this by grinding together the oxide in with the pigments in a (dedicated) mortal and pestle, varying the ratio depending on the effect you want. Then mix with your chosen medium and voila! You can then use the glossy versions on eyes, and the satin versions on hooves and nostrils for an array of appealing realistic effects.
  • Don't like what you just painted? No problem! Just wash it off with water and start again! Overglaze only becomes permanent when it's fired, so feel free to make as many changes you want before that happens.
  • You don't have to paint white markings or patterns! Amen! That tedious chore dreaded in cold–painting is totally circumvented in china painting only because your underlying (glazed) bisque provides the white background, so you simply wipe off the pigment from an area you wish to remain white.
  • You don't need an airbrush to china paint as brushes, sponges, or any assortment of typical cold–painting paraphernalia can be used instead. Keep in mind you'll have to adapt their use a bit, but that's to be expected with any media. That isn't to say an airbrush isn't an immensely handy tool in the glazing studio, however. I find that airbrushing on underglazes to block in areas with smooth, even gradients works better (and faster) than trying to do so with overglazes.
  • You never use water with overglazes, but only your chosen medium(s), thinning with glycerine when necessary.
  • You can keep your overglaze pigments and custom mixes in powder form in a suitably sturdy and tight–lidded container, or you can mix them with your chosen medium and store them thusly that way, too. You can even keep them on your palette (like many oil painters do) given that your palette is air–tight and covered to prevent debris and dust from contaminating the pigments. Gunk in your pigments makes painting a glossy surface rather tricky, and since overglazes fire at much lower temperatures (usually between Cone 016-018), not everything you'd expect to fire out actually will. 
  • Rather than waiting hours or days for your piece to cool down to apply additional layers with underglazing, you can more rapidly apply successive coats in overglazing only because of the lower temps involved. For example, after your kiln shuts off let it drop to about 1000˚F, then you can pop and prop the lid on the lowest "tooth." Then when it drops to 400˚F–500˚F, you can pop the lid fully for even faster cooling. For someone as creatively impatient as I am, this is a big plus! (I work in acrylics and color pencils for a reason!) But as always, exercise your good judgement here, as each piece and each kiln have their own tolerances and parameters.
  • Overglaze pigments fire pretty much WYSIWYG"what you see is what you get." On top of that, how you applied them also is pretty much WYSIWYG (with some exceptions, which I'll share as I discover them). This is in sharp contrast to underglaze where you have to paint "blind," and because chemicals combine and change during the fire, colors may be altered quite a bit away from what you'd expect. For someone who prefers a high degree of control and predictability—like me—WYSIWYG is always very appealing.
  • So far, I've found I get better results if I apply thin layers or washes rather than thick, gunky layers. Overglazes definitely have body, so if you glop it on it will result in a bump or ridge. If that's the desired effect, great! But if not, you can sand it off with a bit of elbow grease (and carefully with wetted wet/dry sandpaper in ultra–fine grit and with dust precautions), refire it, and then redo that feature in thinner layers.

Here we go! My very first interlude with overglazes on my own!

To crunch it all down to one idea thenif you're familiar with oils, watercolors, or inks, these overglaze pigments aren't too far afield in terms of feel and workability. But a few critical words of caution regardless:
  • Many overglaze pigments contain poisons and are highly toxic. So I recommend reading data sheets and sticking with the lead–free and cadmiumfree pigments, no matter how appealing a color may be.
  • Exercise common sense and caution with silica–based fine powders and chemical pigments or mediums.
  • As for mediums, you may come across references to motor oil or other such materials. Just remember that whatever you put into your pigments will be fired at over 1000˚F in your kiln, so safety issues with vapors and flammable materials are important, especially if your kiln resides in your house or garage. 
  • Use dedicated tools and containers for all your overglazing materials since these pigments are totally unlike those used for underglazing or coldpainting.
  • Above all, do your homework and exercise appropriate precautions to stay safe! We want you around to happily glaze for a very long time.

As for the pigments in general, Reusche is a dominant supplier (and made in the US to boot), and having used such pigments provided in Lynn's and Karen's kits, I can say unequivocally that they're wonderful. But here's the hiccup: Reusche sells its pigments only in bulk, which is both very expensive and rather impractical for our purposes. So if you want to sample of bunch of different colors out of curiosity, an eyepopping bill with be the unfortunate result. ACK! Nonetheless, check out Reusche's china painting catalog to get an idea of all the enticing colors availableand that's just one supplier!

Here he is during his final fire with overglaze! In theory, this should be it!

And there are many other suppliers! Better still, many of them offer Reusche pigments in smaller (affordable) quantities, or who may have their own custom colors created for purchase. Check out Ann Cline (recommended by both Karen and Lynn), Kathy Peterson's shopping pages, China Painting Today's store, Maryland China, Rynne China, and Colorific Porcelain, just to name a few. Pigments are typically sold in powder form by the dram. It's hard to say how far a dram would last, though, since we each would work differently and each piece has different needs. But I do hope to have a better handle on "dramability" as soon as I gain experience with a larger body of overglazed work. But I can say at this point that a little bit generally goes a long way!

Regardless, Karen reiterated to two important points to look for while choosing from all those lovely pigments: (1) are they lead–free and cadmiumfree?, and (2) do they all fire at about the same temperature range? Using pigments that demand rather different Cone temps can really complicate matters, so focusing on pigments that are both safe and compatible allows us to concentrate on creating rather than (avoidable) aggravations. Smart advice! With those two tips in my head, I can't wait to go pigment shopping! 

And hey, here's a tip: I'd initially mixed Persian Red and True White, with a tad of Brown (to richen it a bit), to create that coveted pinking tone, only this time in overglaze. But to my dismay, that dang Persian Red kept firing away, even at Cone 022! What was particularly interesting was that it seemed True White was the instigator of this vanishing act as those parts where Persian Red was used almost purely tended to stick better than those areas where True White dominated the blend. So after five attempts at trying to get Persian Red to stay, I got pugnacious and simply switched to another reddish color replacement in my White and Brown mix: Ebony Brown. Bingo! I got a nice pink that finally stuck around! Now on a piece of this tiny scale, you really only need an indication of pink here and there, so I still have to see if this pinking mix would be convincing on a larger piece where bigger swaths of color will be needed. Something to discover! Fun!

And ta–da! I did it! Say hello to GoTime Buster! I bet you can guess where his name came from! Pining for pink ushered in a whole new era for the studio, and I can't wait to really take the bit between my teeth and run with it! Feeling a bit like Buster!

And now to backtrack a bit, back to 2010I found it incredibly exciting that the blues, purples, reds, yellows, and oranges I'd used for underglazing ol' Buster also worked! This opens up even more possibilities since it suggests that our color mixes for underglazes may have more options beyond blacks for darkening and using the underlying white bisque for highlighting. Even more curious, those bright reds (and yellows and oranges) retained their potency a lot better than the reddish brownshmmm. Lots to experiment with in that department now as well!

So hey, here's the deal: if I can do all this, you definitely can, too! Having said that, though, clearly I'm a total neophyte right now. Not even a baby yet, really. Heck, I'm barely a zygote! But it's so inspiring to be literally looking out over a vast expanse of unknown territory, full of promise and peril, and surely with tall tales waiting to be lived and told! So come along with me and we'll chart it together, and here's a terrific resource to get you started! If you're serious about overglazing, too, becoming a member is a great idea because that opens up their archives rich in wisdom and insights.

In the meantime then, pop on over to Buster's album for more images, and also check out his 5day auction on eBay! I still can't believe I actually pulled this off, but it wasn't done alone! With the help and guidance of the wonderful mudhens, I made it up and over my 1,000 foot wall with nary a sweatso thank you gals! So much! You always seem to make the impossible not so impossible after all!

"Let your curiosity be greater than your fear." — Pema Chodron

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