Drywall sheet is a simple product. A layer of gypsum between top and bottom sheets of fibre board.  The difficult part is in the manufacturing process.

The fibre board is supplied in large rolls.  A shaft is fitted through the core.  A standard procedure for most fibre board products.  The shafts generally have “strip fingers” which are pushed out by compressed air to grip the inside of the core.  When the roll has run out, the fingers are deflated and the core removed from the shaft, ready to be fitted into the next roll.
Most of the time, this process works well.

Unfortunately, every now and again, the fingers of the shaft don't retract and remain firmly embedded in the core.  This causes some major problems.

Beware of Being Ambushed

Safety Notes from the Project Engineers Diary

The Preamble