Permanently delete internal faces

[mitcorb]

Sometimes coplanar edge loops on a model re-face internally even after deleting, saving and reopening the file.
Simply deforming the loop out of plane could cause, and has before caused the refacing to "splinter" into multiple triangle internal faces with shared edges.

Any ideas on how to "permanently" delete them?

[pilou]

you have this plug by Wikii remove inner face faces who can maybe help you ?