Wednesday, March 16, 2011

Things you should avoid if you don't have opposable thumbs

The chickens were aggressive bettors. My dad gave them false confidence the first night by letting them win. The next evening, he mopped the floor with them. Honest Abe looked on disapprovingly. "Chickens," he probably never once said, "should not play poker."





Sunday, March 13, 2011

Vacation Days 2-3: Engineering Open House

When we rescheduled our trip to Illinois, we planned dates so that we could attend the University of Illinois' way cool Engineering Open House. The UIUC College of Engineering is one of the largest and finest engineering schools in the nation, and every spring the different departments open their doors for two days of posters, demos, and hands-on displays. We learned about charge and electric current, magnetic levitation, fluid dynamics, inertia, high-resolution imaging, 3D printing, plenaria flat worm regeneration, clown fish sexuality, air pressure and the Bernoulli effect, liquid nitrogen and ice cream, electric cars, fruit batteries, CAT-scans and computer modeling, flotation and boat design, bubbles, tempering, mechano- and photo-sensitive polymers, vehicle simulators, induction, gears, levers, pulleys, magnetic accelerators, conservation of energy, gravity, molecular fluorescence, glue-and-borax goop, high-speed imaging, infrared imaging, lithography, copper electroplating, Prince Rupert's drops, vacuums, air pressure, optical illusions, angular momentum, and a bunch of other stuff. I also learned, with some nostalgia, that the Physics Geek uniform has not changed since I proudly wore it as an Illinois undergrad (corduroys + flannel shirt); and that the university still has lovingly crafted wooden models of intersecting geometric forms squirreled away in the most unexpected places.


For E, two topics stood out: the egg drop and non-Newtonian fluids.

The egg drop involved designing a structure to protect an egg from breaking on impact following a drop from a second-story window. All participants received an egg, a paper cup, two feet of masking tape, and ten xeroxed dollars with which to buy assorted materials (rubber bands, yarn, balloons, cotton balls, popsicle sticks, newspaper). E made a blanket of cotton balls to cushion his egg inside the cup.


S--a German engineer, after all--rigged up an elegant but time-consumingly detailed suspension network of rubber bands inside his cup.


I, the practical potter, spent most of my engineering dollars on quick and easy packing material--wads of newspaper.


The carnage below the window did not bode well for our cargo.

The egg in the plush cotton ball blanket turned out to be our sacrificial lamb, paving the way for our two survivors. We figured two out of three wasn't bad (litotes!).

Although we spent a lot of time with the eggs, the exhibits that occupied us the most were those on non-Newtonian fluids. A Newtonian fluid is one whose shear stress and shear rate are related linearly by a constant known as viscosity. A non-Newtonian fluid is a fluid that deviates from that relation in any way. The most common non-Newtonian fluids have viscosities that decrease with increasing shear rate. The non-Newtonian fluids we saw at EOH were unusual, however, in that their viscosity dramatically increased with increasing shear rate. They were so much fun to play with that we've decided to have a non-Newtonian fluids fest for E's next birthday party.

To make your own non-Newtonian fluid at home, mix cornstarch with water in appropriate proportions (a little water goes a long way). Punch the mixture, and it behaves like a solid; hold it gently in your hand, and it trickles through your fingers. We're told that water, 150 pounds of cornstarch, and a kiddie pool are the necessary ingredients for running barefoot across a non-Newtonian fluid. If you keep things moving quickly, you can also play catch with cornstarch suspensions.

Saturday, March 12, 2011

Vacation Day 1: Chicago

Because it snowed in Durham on Dec. 26, 2010, all transportation ground to a halt that day, and we had to postpone a trip to visit my parents in Illinois. Temps have thawed since then, and on Thursday, we embarked on our rescheduled trip and flew to Chicago.

After landing, we drove downtown and had brunch at a Chicago institution, Lou Mitchell's, where (as is their claim to fame) they give "donut holes to all and boxes of milk duds to the ladies and children."

Desdemona and Roxanne were a little dubious about the breakfast options, while the waitstaff were a little dubious about our photo shoot. You'd think the restaurant had never served chickens before.

Following brunch, we walked east toward Lake Michigan, admiring Chicago's architecture. One building had such stunning gargoylish statuary perched on top that we decided to go inside, whereupon we discovered the Chicago Public Library.

After a restful pause to read magazines in the children's section, we continued on to the exquisite Art Institute. A guard outside told E to stay off the bronze lions, but no one challenged the chickens.

That wasn't the case inside the museum, however. Although the Art Institute permits the use of cameras without flash, one guard seemed nervous about our photographic activities. I explained that we were tourists on vacation from North Carolina, which apparently satisfied him. We spent several hours enjoying the art, and were particularly impressed by the bright airiness of the Modern Wing, which had been under construction the last time we visited.




Friday, March 4, 2011

Post-firing debriefing

As always, I need time to come to terms with my pots post-firing. For example, what I considered yesterday to be disturbing crusty bubbly purple stuff, I now consider (just one good night's sleep later) merely befuddling crusty bubbly purple stuff. But I'm getting ahead of myself. Good news first:

The Moebius Diatom Boxes experienced minimal warpage, and none of the parts stuck together. The photos make them look toastier and bagelier than they are in reality. I expect future MDBs will end up electric or gas fired, maybe with some stains for color, to reduce preparatory exasperation.

My four favorite pieces are square boxes (wheel thrown and altered!) that I glazed top to bottom. They responded beautifully to the soda. The tallest box is about 5" high.

There are two fine pitchers, an excellent bottle, some lush double-walled bowls, a confident teapot, and a juicy green pear (looking artificially green in the photo; it's a little bluer in real life). I consider it a bonus that only one of the pitchers seeps, because--like every other pot I've produced in the past two years that has seeped--they're both made from Loafer's Glory clay. No more Loafer's Glory clay for me (regrettably; it's a lovely clay to work with when it's wet). I have a can of very dangerous highly toxic spray that's supposed to help seal pots, unless the can explodes or the spray poisons you in the process; I haven't tried it out yet, however, because I value functioning lungs, skin, and eyeballs more than I value my seeping pots, but maybe this spring I'll get out the goggles, gloves, and respirator and give it a whirl.


Here are some chickens mugging for the camera:

I will concede that the bubbly crusty purple stuff looks pretty good on chickens. Here's a close up of the crusty stuff on some cups, where it's less appealing (dry crusty stuff and lips don't go well together):

Upon pieces that are strictly objets d'art, the purple stuff is fine. The objet on the left is actually a vase form on its side, though I very much like the spherical look in the photo. I was planning to give up holes for a while, but I think I'm going to have to try making some hole-filled spheres.

On the Double Torus-Multiple Size Hole/Total Coverage Klein Bottle that's been patiently waiting to be fired since last summer, the purple is a little garish against the green glaze. What am I saying, the [w]hole thing is garish anyway:



I will try sanding the crusty bubbles off of pots that should be functional, such as this bowl and colander, as no one wants little bits of heavy-metal-laden glass to chip off into their noodles:

Also in the category of Pots-That-Have-Been-Waiting-Since-Last-Summer are several wheel thrown and altered oval boxes. Alas, instead of using my purple alumina hydrate wax on the lids, I wadded the lids--with the somewhat predictable result that most of the lids warped. Dang. From here on out, it's alumina hydrate wax for me.

In the Total Fail category are several pieces made from a highly recommended ^5-^8 porcelain that I purchased online. I'm used to porcelain being finicky and S-cracking in the bottoms of bowls and cups, but these pieces split in some very odd places. Several tumblers had vertical cracks down the side, often beginning well below the rim and ending well above the foot. In the photo below of the two tumblers, a long vertical crack cuts through the cup on the left, while some beads of water are leaking through a crack in the cup on the right. The salt-rock pear has a horizontal crack across the top that is, as far as I can tell, completely unrelated to the form. Homer Cat doesn't mind the cracks in the tumblers, since all he sees are People Cups, but these pieces are headed for the trash can. I bisqued all of my porcelain pots well before the outside temperatures dropped below freezing, so I'm at a loss to explain the defects. Schade.

To end on a more positive note, here are some non-crusty, lid-fitting oval jars (does that count as litotes?), and a picture of a flattery* penguin chatting it up with a chicken at an office party (penguin and penguin photo by Bob F.).

*as in, "imitation is the sincerest form of..."

Thursday, March 3, 2011

Unloading

We unloaded the kiln today. Serene Wadding Buddha got a hefty dusting of black soot plus some disturbingly green mystery powder, yet still he sits contentedly on his mat with his wee bird companion and cup of tea (which is not 3/4 full of unmelted glaze). Nothing fazes him.

Here are photos of the front and back stack:

What's that, you say? It looks like something is amiss with the far end of the bag wall*? Why, you're right! It collapsed during the firing. Fortunately, it slumped sideways into the kiln wall rather than tumbling onto the loaded shelves. Casualties included just two bowls, a cup, and a chicken, none of which fell from the wall. Thanks, Serene Wadding Buddha (and to you too, Chipper Dog, of whom I have no post-firing photo)!


The pots were a little dry this time, with a bubbly purple crustiness I've never seen before. If you are less uptight than I am, or if crusty bubbly purple stuff is your thing, or if you are able to squint in just the right way, or if you are one of fifty or so clay chickens, you might be able to find such random and non-replicable surface treatments not entirely displeasing.** I'm working on it. Cedar Creek potter T.T. wondered whether the kiln might have been fuming copper or tin left over from a previous firing ("A.B. sometimes puts pretty wacky stuff in the kiln..."). Indeed, Serene Wadding Buddha's dusting of green looks suspiciously like copper carbonate. Fortunately, a few glazed gems are mixed in with the crustiness. I'll post some photos soon.

*I don't know why a kiln's bag wall is called a bag wall--OED, how could you fail me so?--other than that the bag wall protects the pots by creating a bag of air between the pots and the burning fuel. OED does offer a definition for bag from 18th-century coal-mining lingo that seems to make sense here--"a cavity filled with gas or water."

**I recently learned from a friend that the rhetorical term for these backhanded compliments is litotes.

Tuesday, March 1, 2011

Sneak peek

I went over to Cedar Creek and took photos through the peeps. No puddles of melted clay, no sand-papery unmelted glaze: I shall sleep well tonight.

It's hard to see in the first photo, but I can tell you that the chicken sure has some fine ash on her...