Post #411568 by Babalu on Fri, Oct 3, 2008 10:47 PM

Hey Mike and Henrick...Using this low fire clay, I've have had a few pieces lately form hairline cracks during dry out...mostly on the inside of the mugs that don't go all the way through. Lucky, none of these hairline cracks seemed to grow during the bisque firing. The cone 06 glaze used on them seemed to cover the cracks to the point that you couldn't even tell they were there. I'm guessing that some of this is due to the low fire. Henrick, I'll bet the cone 5 clay you are using still goes thorough quite a bit of shrinkage in the glaze firing? This clay I'm using right now really does not shrink anymore in the glaze firing.

CRACKS SUCKS!!

I have a few mugs with these cracks in them now which I am candling at 200 degrees all night tonight in the kiln...I'll ramp the kiln up in the morning. Cross your fingers, I would really like to see this kiln load turn out well.

Mike did you mug have the crack in it's greenware sate, or did it become present after the bisque firing? Can you show a picture maybe?