A method is provided of cleaning of a portion of a mold component, the portion of the mold component including a passage configured, in use, to allow passage of fluid and to prevent passage of melt, the method comprising: entering the mold component into a cleaning configuration, whereby a portion of the passage becomes part of a molding surface; performing a molding cycle to fill in at least the portion of the passage with molding material for incorporation and removal of a residue there from. Also provided is a mold having a first mold half and a second mold half, the halves being movable relative to each other. A mold shut height adjustment apparatus can provide for a change in the mold shut height