On 24/11/2013 05:47, Gib Bogle wrote:
I found a long post online by someone who sounded as if he knew what he
was talking about.
http://www.diychatroom.com/f4/removi...acement-30292/

(you have to scroll to the bottom)
He said apply a mixture of linseed oil and chlorine bleach with the
frame lying flat, for a day or so. Apparently the linseed oil will
penetrate into the putty and soften it, while the chlorine attacks the
calcite in the putty (which is made from high-calcite lime and linseed
oil) and does something. Anyone tried this?

As it's summer down your way, that might be worth a try!
I'd break the glass first and use the shards to prise the putty away
from the wood. If the putty is still soft inside (and it's amazing how
much of it is), it should separate easily