Wednesday, June 17, 2015

If we Learn From our Mistakes I have a Great Learning Opportunity!

 
The dragon shepherdess' cottage, just out of the kiln, doesn't actually look that bad.  But it's not what it seems.  There are several cracks and breaks.

The worst one is on the roof.  Despite my hopes and dreams, the house dried just a bit to big to fit into my kiln.  So a local ceramics place bisque fired it for me.  (I was hopeful that when it was bisque fired and not so fragile I'd be able to get it into my kiln for the final firing.)  But a corner of the roof (on the round part) popped off with the minor bump it got when I put it into the back of my car.  I fixed it with patch attach and it made it through the bisque firing.

So I glazed the house and went to put it in my kiln only to find that it was a bit too big.  BUT -- turns out - good news and bad news - that the roof was loose from the bottom and each piece would fit separately.  So I fired the roof first.  The patch attach joint failed and the supposedly repaired broken piece separated badly.  Also, a crack appeared at the bottom of the back left edge - but not along a seam!  It was tempting to give up at that point, but I wanted to see what the glazes on the bottom part would look like, so I fired it.

As soon as I opened the kiln, I could see that one end of the threshold piece had separated.  But the rest looked OK.  After the kiln cooled to a bit over 200 degrees, I took the piece out.
Then the freaky stuff started.  A joint in one of the inside corned pieces separated with a loud snap.  Later the other joint snapped and that corner piece separated entirely.  The noise was kind of scary.  It sounded like heavy glass breaking.
Then, when I turned the piece a little to take a photo, a long crack sliced its way through the solid piece of the back wall.  Soon another crack, but shorted, opened up by the front door opening.

Clearly I have a lot to learn about constructing and firing larger pieces.  And I'm thinking maybe stoneware, at the higher temperatures, is more susceptible to these kinds of problems than earthenware, but I don't know.
At least the owl's cute!

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