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
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