plaster of paris cracked?
Hii my plaster of paris cracked. i want to turn a 250x500 cylinder of plaster of paris on a lathe for a positive for slipcasting. its mounted onto the faceplate with a pine plank in the middle to help with the support of the plaster we made that last week thursday and all was fine but this morning it had a big crack in the length of it. what might cause it