I would be interested in knowing which "ENTEK" broke down with the apparent hot spots. You mentioned anti-ox, this would suggest ENTEK CU-56, a monomolecular coating which will break down at temperatures above 170F. ENTEK PLUS CU-106A is a more robust coating which can pass through several thermal cycles. Please clarify. Tom Eshelman Enthone-OMI [log in to unmask]