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cracked plates and cracked shelf

updated tue 5 jan 99

 

Melissa Carpenter on mon 4 jan 99

Hi Galen and Michele! In response to the problem of the cracked serving
plates, it has been my experience that placing wide flat bottomed pieces
on the bottom or the top shelf has everything to do with their
cracking. Especially if you leave the vent fan on after it kicks off.
The cool air being drawn in at the top produces a somewhat uneven
heating and the bottom of the kiln always seems to cool fastest which
again produces an uneven heat. If you processed your reclaim in the
usual way and it contains trimmings and not just throwing water then I
think the issue is with the uneven heat. This relates to Michele's
bottom shelf cacking as well. Most of my bottom shelves eventually
crack and I have taken two approaches to this. First, as was your guess
I support the shelf under the crack, but once the crack is large enough
to look threatening I force the crack and break the shelf in two. Then I
either support it well under both halves or I utilize the odd sizes to
better fill a load. If you leave the broken shelf on the bottom you
should be aware that it could be a little uneven. However, since I
never put wide flat bottomed pieces on the bottom (as was my advice to
Galen) I don't have to worry about something sitting over the crack. :)
Hopes this helps,

Melisa Carpenter
Claytime Studio
State College, PA
Claytime@vicon.net

Please know that all comments are simply my humble opinion. :)