Help with edges, some spikes

[SueW]

I have just starting using my Cress Kiln, and have managed to get some wine bottles with nice rounded edges, now I tried a platter which is fairly shallow shaped like a fish. I cut my glass accordingly and when fired I have very sharp spikes, but only on part of the sides. What did I do wrong. The mold is a clay one. Can anyone help. I live on a island so this has to be a self learn thing. Thank you

[Carol]

How many thicknesses of glass did you fire? One or two? It sounds like it may have been overfired on one side...that can cause little needlelike projections.

[Barbara Muth]

If you are just starting out, I strongly reccomend Brad Walker's book, available for purchase through this website. reading that book will help you to understand a lot of what hapens when you fire glass.

Enjoy the ride!

Barbara

[Kitty]

maybe one side of your project was closer to the coils, and got too hot. i think we need a little more info, like what kind of glass it was, and the temperatures. i've got a small Cress myself. and greetings from one island to another. kitty.

[SueW]

Hello again and thank you all for your replies. I used only 1 layer of glass and it was textured. I don't know the brand name of this glass as it was a freebie given to me. It looks like it would have come from a store window. Amber in colour. I will look into purchasing the book. Thank you again Sue