Sonny wrote:
I used regular paper tape,
and it seems that is where it is occuring.

Is the mud, only, cracking or can you tell if the tape,
itself, is rising (peeling up, separating) from the drywall
surface?

If you can be sure only the mud is cracking, then you are
caking the mud too thick and, as it dries, it will form
irregular cracks, usually in all directions, like in a
dried-up mud hole cracking irregularly from drought. This
isn't bad. Allow it to dry completely, gouge out or scrape
(not sand), somewhat, those areas and skim it again.

If your tape adherence, to the drywall surface, has failed,
this means you didn't put enough mud behind the tape for it
to adhere properly OR You may have initially put enough mud
behind the tape, but you pressed the mud out from under the
tape (when skimming, too tight, that first mudding/taping
layer). The cracking, due to this lack of mud behind the
tape, will likely be a straight lined crack along the edge
of the tape (and not the small irregular type cracks as
that of a dried-up mud hole). If this is the case, cut out
the mud and tape, from the affected areas, and re-mud and
tape. If this is the case, you may have mudded and taped
improperly, this way, over other areas and your problem may
very well show up in those other areas, later.

I hope your problem is the thick mud problem and not the
non-adhesion problem.

Sonny

Good post, Sonny! Thanks!

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