Search the Community
Showing results for tags 'prototype'.
Found 2 results
Hi, We have been doing the jigger for the first time and the pieces whatever we are making have a cracks in a same pattern in a same location, and we are using Terracotta clay to make the pieces and here I m attaching the cross sectional pieces of the molds., and in the molds I have few doubts and I would like to get clarified so that I can reduce the cracking doors one by one., Does the thick and thin portions of the molds absorbs water differently so that the pieces are cracking ? As you can see the picture of the pieces the cracks are happening in the place where the side wall is connecting with the curved edges, and the cracks are happening only with our terracotta clay and we have tried quite a lot of receipes to avoid cracks but nothing is helping out and the cracks are happening in the inside of the pieces and the outside wall is just fine. Also we have tried jiggering few pieces with our stoneware clay and we havent have any cracks in the stoneware. Does the uneven wall thickness is the reason to get the cracks ? Wi only the Terracotta is cracking and not the stoneware ? Wi the inner wall is cracking and it didnt extend to the outer wall ? Does it anything to do with the plasticity and the composition of the clay? As far as the design is concerned, we make sure theres no undercuts in the design and even the wall is not striaght and it has an angle of 10% for easy releasing., we used to have few issues with our clay body which I was working with Tom (Glazenerd) to solve the issue, but apart from that I would like to know what are the other possible reasons for the cracking.
I finally got around to trying out my own version of Marks wonderful thrown sponge holders. I used my extruder to create the walls and a slab for the base. I did two slightly different versions. The one on the left in each picture I cut the walls all the way to the base, it seemed kind of floppy and unstable, but might firm up ok once drier. The one on the right in each picture I left about a half inch lip connecting the walls, it seems a bit more stable. Not sure if I am going to need to curve the corners of the walls a bit or if the whole thing is going to warp when fired. I guess I'll see won't I! These are still in the wet stage and have them wrapped up overnight, in the morning I will unwrap and loosely drape and start the drying process. I am not going to decorate or do anything special with these as I don't want to invest too much in what could very well be a flawed design. If they both survive the kiln I will decide which I like the look of better and use that as my pattern from here on. Once that's decided I can have some fun with the decorating and texturing like I like to do.