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      Ceramic Arts Network is looking for two new forum moderators for the Clay and Glaze Chemistry and Equipment Use and Repair sections of the Ceramic Arts Network Community Forum. We are looking for somebody who is an active participant (i.e. somebody who participates on a daily basis, or near daily) on the forum. Moderators must be willing to monitor the forum on a daily basis to remove spam, make sure members are adhering to the Forum Terms of Use, and make sure posts are in the appropriate categories. In addition to moderating their primary sections, Moderators must work as a team with other moderators to monitor the areas of the forum that do not have dedicated moderators (Educational Approaches and Resources, Aesthetic Approaches and Philosophy, etc.). Moderators must have a solid understanding of the area of the forum they are going to moderate (i.e. the Clay and Glaze Chemistry moderator must be somebody who mixes, tests, and has a decent understanding of materials). Moderators must be diplomatic communicators, be receptive to others’ ideas, and be able to see things from multiple perspectives. This is a volunteer position that comes with an honorary annual ICAN Gold membership. If you are interested, please send an email outlining your experience and qualifications to jharnetty@ceramics.org.
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Bill T.

Bottom Is Cupping Up

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I was loading a bisque fire today and noticed that a 7" covered casserole that I had made about a month ago was cupped upwards in the middle instead of being flat on the bottom.  Why did this happen?  I put ware on sheetrock to dry, place the lid on the casserole, and if it is real hot outside loosely cover with a plastic sheet. ( We have just dropped into the low 90's after a month of close to 100.)  Using Laguna Speckled Buff, quite a big of grog.  The bottom is about 1/4 -3/16 thick, and I compress it well.  I am thinking the bottom dried too fast in relation to the rest of the casserole.   Any thoughts?

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Several causes-thats a thick bottom at 1/4 inch-but if the walls are also 1/4 that should not be an issue.

Its a drying issue most likely-

Not much air can get to middle inside bottom and with the lid on its also a moist inner space. Thats my guess

Mark

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question, why are you covering it with plastic at all? they are both the same consistency when you make them, is it because of added things like the knob and handles?  was it still covered in plastic when you were ready to fire?

 

this is not that uncommon with flat work.  covering the pot helps with the lid fit but it does keep the inside damp.  try removing the lid and letting them dry separately once they become firm leather hard. keep an eye on things as they dry and gently bend it back before it gets too stiff.

 

using the drywall is ok. slide it around to a dry spot occasionally and next time put some weights, (the glass pebbles for flower vases work great) in the bottom.  move it to some kind of wire rack with air under it when it gets very stiff.   if you inspect it as it drys and notice it again,  push in gently from the top before it is too stiff and add more weight.

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Thanks for the comments.  I did think that it got too dry on the bottom and being closed with the lid kept the inside damper.  Will use some of "old lady" suggestions next time.  The plastic was used mainly for the top had an attached handle, and with the heat we have been having I learned the hard way to try to control drying of the two parts.   

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