1333 degrees f or 723 degress C. Simple as that. The longer you keep it in the deeper the cch. If you keep it in 1.5-2 hrs then you effect just 1-2/3 thou of the outside of the action.
Ray St Ledgers here in the UK I believe keep it in for longer..but they have generations of experience unlike me who is a mere amateur...as Ed likes to point out.
Bottom line is if you keep within known tolerences you are 99.9% fine. Go over or piss about and you are in danger of warpage and splints/cracks.
...and here's me saying I would'nt post on this thread again...
T
