On Mar 17, 11:10 am, wrote:
In a bedroom, I need to build a new interior partition 90 degrees off
an existing wall. The existing wall is painted (Benj. Moore eggshell
latex) and the new construction will need to be taped at the corner
where they join together. Can I just tape this corner like it was all
unfinished drywall, or will I need to prep the existing painted
surface to affect a good bond and sound tape joint?

Perhaps use a J bead at the end of the new partition and allow a
clearly defined joint to be visible.