The construction is fairly straightforward: I first threw some ridged (not rigid) discs about 3/4 of an inch thick on a plastic bat. I set those aside while I threw 4 almost vertical—they tilted inward– walls with a gallery at the top but no floor; also on plastic bats.
By this time, the discs were set up enough for me to wire them off and throw them out on the canvas covered table, stretching them into ovals.
At this point, I also threw out several slabs for what would eventually be the lids. You want all the clay involved to be about the same dryness so that it is all shrinking at about the same rate.
The timing on this altering of pots is crucial.
Too wet, the walls tend to cave in or flop around and the oval is at best, overly controlled by your hand, at worst, a total asymmetrical failure.
Too dry, and the rim cracks as you try to force it beyond what it was once willing to do. If you get it right, the clay chooses its own curve; a delicious, aesthetically pleasing curve that the clay knows so well how to do. You see this curve most often in handles.
Back to the walls which had I wired off and, making sure they slid easily on the slippery plastic surface of the bats, gently –squeezed is not quite the right word–“encouraged” them to be oval as well.
Once this oval sets up, you can set it on the (now)oval disc base and trace around the inside. Score outside that line, then turn it over using a second bat and score the underside of the base of the wall, wet it (I used magic water) and then set that on top of the scored disc base to join wall to it, trimming off any excess on the outside and sealing it by going over it with a soft rib- you can also use the soft rib to give a curve to the edge of the base.
Once this is sufficiently set up- wet-leather hard, you can turn it upside down on top of your slab and again trace the oval (the outside this time) to cut a lid. Add handles to the sides of this casserole if you like and drape the now oval slab inside the opening of the top- separated by a piece of plastic.
At this point, before it is any drier, I coat the entire thing in black slip. When the slip is also leather dry, I carve.
These had a lot of surface area and the carving took a considerable amount of time. Of the 4 I did, 2 came out beautifully, the lid of the smallest one warped in the glaze firing but it’s the 4th casserole I want to tell you about.
The last was quite nice but as it dried (and I dry them slowly under a loose cover of dry-cleaning plastic) the walls were proportionally too thick compared to the floor and they pulled away leaving the floor cracked on the sides. I discovered this when the pot was pretty much bone dry.
There was really no way to realistically repair it- especially since the entire outside surface had been delicately carved. I certainly could not spray it down- the slip design would have run and been destroyed. I was pretty upset about this until Dave Trost, a fellow teacher at Lill, told me about his method of re-wetting.
He told me to take one of the slabs of plaster –they have many at Lill for drying slurry and clay scraps- they are about and inch and a half thick; and to soak it in water until no more bubbles rose off its surface. Then to take my pot and set it on the plaster and wrap the whole thing tightly and let it sit.
Well, I had nothing to lose –I had already invested at least 4 hours in the pot-so I did just as Dave suggested and then double wrapped it in plastic and let it sit on the shelf for at least two weeks maybe more.
When I finally got back to it, the clay was back to a pliable leather hard consistency!! I was able to push the walls back in, reinforce the bottom and repair it.
Then to slow down the drying of the floor this time- to keep it a little more pliable should the walls pull on it as they were drying- I waxed the entire bottom inside and out and then waxed all the handle joins just to be on the safe side and set the piece to dry lightly covered in plastic again. This time the piece made it to the bone-dry stage and is being bisked as I write this. I will keep you posted.
Sadly, I did not take photos during construction. If I make more (and these were popular) I will post them.
Addendum: Okay, the casserole made it safely through the bisk, I glazed it and waited on pins and needles to see if it would split apart in the glaze firing and it did NOT! It came through intact with a few cosmetic cracks but is fully functional! Here are some photos: