View Full Version : Stress

Cecil McKenzie
05-01-2012, 08:43 PM
My wife cleaned a piece of glass that I made in college in 76/77 . She used lukewarm water and rinsed it off and dried it. About an hour later we heard a loud crack and investigated and found that piece broken but standing in one piece. It was surprising to me to see a piece that has been knocking around for forty-four years suddenly just break like that. I guess just because something has been around for a long while does not mean it is stress free. The glass was melted Dr Wells bottles ( an early alternative to Dr Pepper) and the same glass with some copper carbonate added.

Pete VanderLaan
05-01-2012, 10:37 PM
I'm never surprised by that. It is likely that it was poorly annealed if it didn't use color. I wonder frequently if the work made all through the 60's and into the 70's has fundamental issues.

At the same time I think glass does become more sensitive to temperature changes as it ages. If you were to take a piece of cut crystal from the turn of the 19th century and filled it half way up with tap water, odds are good that it would be cracked down the middle after a few hours. Old cut crystal is to admire, not to use.