i did some work with glass in a science class in grade 9. glass won't shatter because of the heat. we would heat a glass tube up over a gas burner and bend it into shapes. what you didn't want to do was drop it into cold water. the thermal shock would cause it to break. i split my thumb open trying to bend the glass when it wasn't ready to form.
how do you think glass is formed? you heat it up to around 1800f (not 100% sure on the temp) and then in becomes close to a honey consistency and you can mold it. you can also cool it down slowly and it goes back to the way it was. no issues at all.
how do you think glass is formed? you heat it up to around 1800f (not 100% sure on the temp) and then in becomes close to a honey consistency and you can mold it. you can also cool it down slowly and it goes back to the way it was. no issues at all.