Hi!
Look at this glaze recipe for 1230°C (cone 6)
neph sye 30 / wollastonite 8 / colemanite 21 / EPK 10 / silica 31
I tested it and resulted very nice! But then I glazed an object and the glaze spit on the kiln shelf.
The pictures attached show how is the testing tile, how resulted the object and what was on the kiln shelf...
For spitting problems I already asked the forum several times, because sadly I continue to have this problem. So following your previuos advices I tried to decrase boron content, to apply thinner the glaze (and sometimes it worked) and to cool slowlier.
In this case I double layered the glaze (but it was not too thick) and I slow cooled. I know the boron content is high in this recipe, but do you think is the only problem?
Thank you a lot!
Paola