Susie Posted January 30, 2011 Report Share Posted January 30, 2011 Okay, a newbie question - when a clay body is listed as having 11% shrinkage, does it shrink 11% in the bisque AND the cone 6 firing or is that the total shrinkage after both firings? Is absorption rate important? Thanks! Link to comment Share on other sites More sharing options...
Chris Campbell Posted January 31, 2011 Report Share Posted January 31, 2011 I have always taken that as shrinkage from wet to fired to maturity. Don't know about absorption rate. Link to comment Share on other sites More sharing options...
bciskepottery Posted January 31, 2011 Report Share Posted January 31, 2011 Absorption rate is important for functional ware, especially items going into a dishwasher, microwave or oven. The lower the absorption rate, the more vitrified the body. Link to comment Share on other sites More sharing options...
Matt Katz Posted January 31, 2011 Report Share Posted January 31, 2011 Okay, a newbie question - when a clay body is listed as having 11% shrinkage, does it shrink 11% in the bisque AND the cone 6 firing or is that the total shrinkage after both firings? Is absorption rate important? Thanks! It is impossible to know without confirming with the source of the data. Absorption is very important. Ideally you want absorption as close to 0.5% as possible (basically within the margin of error of 0%) Link to comment Share on other sites More sharing options...
Susie Posted February 3, 2011 Author Report Share Posted February 3, 2011 The data is from the Highwater Clay specification on their Little Loafers...at cone 6....11% shrinkage...1.87 absorption. I'm not trying to get overly technical, just trying to figure out how big to make something so it will be the size I want after its fired. Have a few tiny mugs in my collection. thanks for the help! Link to comment Share on other sites More sharing options...
bciskepottery Posted February 3, 2011 Report Share Posted February 3, 2011 You have a couple of options. One is a shrink ruler available at many pottery supply stores that is calibrated to different clay shrinkage rates (8%, 10%, 12% and 14%). Or. use the shrinkage rate to calculate the size. A six inch tall cylinder at 11% shrinkage would need to start out about 6.7" tall (6" x 1.11 = 6.67). Or. 11% of 6" = .66"; 6" + .66" = 6.7" Link to comment Share on other sites More sharing options...
Susie Posted February 10, 2011 Author Report Share Posted February 10, 2011 Thank you!! Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.