Playing footsie

Casting a glass foot for Cinderella

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Why is it that the simplest projects have the biggest potential to drive you up a tree?

If you’re a regular reader of this blog you might recall me mentioning talented sculptor Maria Wickwire Palensky. She approached me last spring about casting a transparent foot and ankle for one of her sculptures.

Among other things, Maria interprets ancient mythologies surrounding women. Her work is stunningly beautiful. My friend Les and I headed up to her house in the mountains (where I especially fell in love with Persephone, below).

Maria had a problem: She’d engaged a glassist to cast part of a sculpture in transparent glass, but after several months’ work the project had failed. Could I take it on?

The work in question, Cinderella Story, was a lovely half-life-size clay sculpture of a woman in a leotard. Instead of a glass slipper, however, Maria wanted this lady’s foot and ankle to be pale yellow glass.

The foot was extended, almost cylindrical in shape. Maria had the master mold made by one of the best moldmakers on the west coast, Leslie of LASH Molds. That mold was a thing of beauty, causing instant mold envy (I wish MY molds looked that good).

Casting a glass foot? Now, I’m not a huge fan of transparent casting–transparent glass tends to eat the very intricate detail I put into my glass–but neither of us could see a whole lot of difficulties in casting what was essentially a 10-inch glass cylinder. So no problem, we said....but in fact this project has met delay after delay, to the point that Cinderella Story remained footless until her debut in Art in the Pearl last weekend. Even now, the glass foot she’s wearing is temporary. More on that later. I gotta say I’ve been having a real learning experience as I work through all this stuff:

April: Mold issues
The piece needs to be perfectly transparent, at least at the toes, and the best way to do that is to construct a reservoir above the mold to allow the glass to drip in. However, the existing mold would be as tall as my kiln; adding a reservoir would mean I couldn’t close the lid.

I choose to angle the mold until everything fits, about a 60- to 75-degree angle that will still allow enough slope for gravity to slide the molten glass into the toes. It takes extra time and planning–and the discovery that THIS silicon mold really bubbles the wax unless I spray 4x the amount of mold release I usually need–but at last I have a stable mold.

May #1: Glass issues
Finding the right shade of glass is a much bigger problem than we thought: None of my usual casting glasses work. Maria wants just enough yellow tint to keep the glass from looking perfectly clear, but no more. I buy samples from Bullseye, Uroboros, Gaffer, show them to Maria: Too dark, too brown, too gold, too green. The Gaffer light yellow is perfect when thin…but too dark at the thickness we need.

I haven’t used this color of Gaffer before so I check the Gaffer site, see no particular issues called out for working with it, and propose cutting the Gaffer with clear (in casting, that’s the equivalent of adding white when mixing paint). She agrees, the Gaffer arrives, and so I “mix” my test billet, i.e., I chop about 6 kilos each of clear and yellow, dump them in a reservoir-shaped mold so they’ll mostly mix together when fired. I’ll cut it again with clear until we get the right shade. The actual billets will completely mix as they drip into the mold. I set up the kiln program and start firing.

May #2: Kiln issues
That is, I try to fire. The house loses power with the piece just getting to process temps and the mold cracks. I reset everything, make a new mold and fire again. (I probably could have gotten away with firing in the original mold, but why take chances?)

June #1: Back to glass
This time the firing is fine…but the glass isn’t. It’s turned into the most beautiful burnt orange I’ve seen in a long time. Since I was expecting pale yellow, though…drat.

Can’t find info on why, try cutting it with more clear and it doesn’t seem to make much difference: burnt orange. The US Gaffer folks want to see the glass before they’ll comment. Since the GAS show is coming to Portland a couple of weeks later and I know Gaffer will be here from New Zealand, I decide to wait and catch them at the show.

At the show, the Gaffer reps tell me this is a known problem. “What you’ve got to do is ‘crash-cool’ the kiln down to the annealing temperature or these glasses will go dark on you.” Hmmmm. It would be nice if (hint, hint) some mention was made of this particular characteristic of Pale Yellow on the website…

June #2: GAS, anyone?
It’s great actually getting to talk with Gaffer at GAS. Unfortunately, nothing much gets done on the foot, since I can’t work GAS and the foot at the same time.

I have, however, figured out how to crash-cool a 1525-degree kiln with a heavy, broken lid (it involves borrowing protective gear and reengineering the struts a tad). Post-GAS, I finally have time to break up my pretty burnt-orange crystal into a new reservoir mold, toss it in with a couple other pieces and fire…

July: Kiln redux
…did I mention the great kiln disaster that left me kilnless this summer? Well, the corrected reservoir mold is the third piece in the kiln when the controller blows up. Drat–the kiln is d-e-a-d dead.

We’re running out of time and Maria’s definitely getting nervous. I seek a tall casting kiln to rent. Press of work means I won’t be there to crash the kiln and avoid browning up my Gaffer crystal, so it’s time for a new glass. Maria’s second choice is the Uroboros Citrine.

August #1: I find a kiln
I’m taking no chances on THIS firing; I make TWO molds, stick them in my borrowed kiln and check them carefully for problems before filling. They look good. Since I can’t get into the building at 3AM I’ll need to add time to the dehydration cycle so the kiln can be closed up at a reasonable hour, but that only delays us a few hours.

I initiate the firing program, email Maria to let her know things are finally going well and…

August #2: The heat
…next day I get a call from the kiln owners: The kiln’s at 800F on the upramp but would it be possible to shut it off and delay firing until the weather cools a bit? It’s going to be 101F in glassland today (actually it got up to 104), the kiln’s in a workspace without much air conditioning…

Trouble is, Maria’s got to have this piece for a show in less than two weeks, it’s a 5-day firing, the mold’s already dehydrated and too fragile to refire, we need enough time to coldwork and mount the foot (and to recast if something goes wrong), etc., etc. We compromise and hold the program at 500F until the workers have gone home for the weekend. That way the hottest temps will happen while nobody’s there. Adds a couple days to the firing schedule, but that’s better than losing the mold. So we fire…

August #3: The dents
…and the feet come out of the molds absolutely perfect, unbelievably gorgeous… except for mirror-image dents on the top of each foot.

At first, I’m thinking that some plaster got stuck in the mold, but realize that the plaster bits would have needed to defy gravity to land in those positions. Thought it was cavitation, but was informed by multiple casting experts that it didn’t look like it, it looked like stuck plaster.

August #4: Recasting
So I take the feet home, knock off extra reservoir glass and do some minor cleanup, then fill in the dents with wax bondo and reinvest them. Somebody else is using the kiln I need to rent, so I have a few extra days to refine it.

I shorten the firing cycle as much as I dare to make up for it. It causes a bit more mold cracking and flashing than I like but otherwise the feet are fine. Dents completely mended. I bring them home, coldwork a bit and begin fitting them to the sculpture…

August #5: The fit

…which turns out to be a pain. Maria was playing in new territory, so the sculpture was designed for a detachable CERAMIC foot, not one in glass. The mold put the glass reservoir at the top of the ankle, and that means that where glass and ceramic join is extra glass that needs to be carved away and fit to Cinderella’s calf. This wouldn’t be a problem if there were some sort of a socket to let me slap on some silicon, insert the glass and conceal the join. Instead, what I have is an angled and bumpy ceramic surface that my glass must join, perfectly flush, or the seam will be very, very visible.

Knew this going in but there wasn’t much I could do about it. Still, it’s tougher than I thought it would be,  finicky, tedious work that proves that not becoming a dentist was an excellent career decision. After a lot of trimming and fitting (and Maria trimming Cinderella a bit), we finally have an attachable foot. This is great except…

September: Back to color
…the foot is the wrong color. The foot is lemonade on a beautiful summer day, absolutely gorgeous and delicate and light, lovely enough to simply stand on its own…but in the right light it’s also too cold for the warm, warm gold of the clay.

At this point, pulling the covers over my head and sleeping for a year or so seems very, very desirable.

Maria’s attached the lemonade foot temporarily, just for this show (and also told me about what else has been going on with her sculpture that makes me wonder if the kiln gods truly do NOT want Cinderella ever finished). Post-exhibit, when I have the new kiln, I’ll be testing new colors to get something closer to warm maple. Amber, maybe, or even a coral, and we’ll recast for a permanent foot this time.

Sigh. Well, at least I’m getting a lot of practice with this mold. And I’m keeping one of the lemonade feet on my desk as a reminder to stay humble.

2016-05-16T14:14:51+00:00

6 Comments

  1. cynthia September 10, 2008 at 7:58 am - Reply

    Now the irony of this, Peter, is that the color of THAT foot looks just about right. Of course, I’m so drunk on clear yellow, amber and orange glass right now that ANY color probably would look right. And, actually, I’m not going to think any more about foot colors until I’m about to hit the switch on the new kiln. (she said in her most Scarlett voice)

    Jenn, Kat, thanks for the lovely compliments; I can’t take credit for the sculpture, that’s all Maria’s and I agree, it’s really a lovely, delicate foot. When you cut Rhubarb with clear (at least the couple of times I’ve tried, the green seems to get stronger, but like I said…ain’t gonna think about that right now. 😉

  2. Peter Cummings September 10, 2008 at 12:38 am - Reply

    Just to confuse you.
    http://www.craftvic.asn.au/events/MonthAboutMaking/IntheMakingCatalogue/horton.html
    The maker Ede is a lovely lady whose work always stops me in my tracks to say what is going on here? Cinderella does the same. Love it. What a challenge though.
    Peter
    Peter.

  3. Kat September 9, 2008 at 4:58 pm - Reply

    Rhubarb would be green in fluorescent light. Did I show you Cork? Or was that also too amber? It is lighter than Straw.

    Those are some pretty feet!

  4. jenn September 9, 2008 at 2:02 pm - Reply

    I am sorry there was so much hell involved. We have all had those jobs. But my god, those are some gorgeously cast feet.

    Maybe try Rhubarb – (cut with a hell of a lot of clear)

  5. cynthia September 9, 2008 at 10:34 am - Reply

    Don’t laugh; that’s about what it came down to when we thought the foot wasn’t going to fit. (Well, actually, Maria fired the original ceramic foot at the same time as the sculpture, so she would have replaced it and made an entirely ceramic sculpture if we hadn’t been able to finesse the lemonade foot.)

    But I looked at the feet on my light table, with the light shining up and making them glow…and started thinking how beautiful this would be as a forest of glowing feet…so at some point I may do the reverse and make a bunch of limbs without a body… 😉

  6. chaniarts September 9, 2008 at 10:03 am - Reply

    why not a version of venus de milo, except with missing feet rather than arms?

Comments welcome! (thanks)

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