refiring glass sculpture in new mould

Judi Charlson · Post by **Judi Charlson** » Wed Nov 19, 2003 5:12 pm

After three unsucessful firings of a large piece containing a negative plaster sculpture I have decided to try one more time.
The first time there was a power outage during annealing
The second time the relay box to the controller blew a fuse
the third time two rings of elements burned out in the kiln.and it annealed unevenly for 8 days
Maybe this piece is cursed but I feel determined.
I am also a little scared because I will be firing in my brand new kiln.
Here's my worry:
The glass shape was in three pieces and I held it together with tape while I carefully fashioned a new soft plaster into the sculpture form and then made a new mould around it. When I turned it over the glass was level with the sides of the new mould. It has been melted(and melted and melted)so I don't expect the glass to "melt down into mould,
BUT will it flow over the sides when I melt it again so that it will heal?
Should I try to add on to the sidesof the mould so that the glass is below?
Can anyone advise me?
Thanks
Judi

charlie · Post by **charlie** » Wed Nov 19, 2003 5:22 pm

think volume. where's the extra glass going to come from to overflow? the heat will make it expand just a little bit, but it will probably form a meniscus rather than flow over.

Judi Charlson · Post by **Judi Charlson** » Wed Nov 19, 2003 5:46 pm

Charlie,
Thanks for your reply.
I think I invisioned it bubbling up and moving around at the melt point,the way water boils and then spills over.
I think I will set it on grog as per usual and spread some extra aroumd mould-- just in case.
Judi

charlie · Post by **charlie** » Wed Nov 19, 2003 5:49 pm

if you're boiling glass, you're way hotter than fusing temps, like maybe 2400+