A cementitious press mould filter assembly 51 comprising a carrier plate 8 which has a first carrier portion 56 with a number of perforations 60, a carrier body 58 and a filter 50 comprising a filter sheet 52 mounted on a filter frame 62. The sheet 52 may be attached to the frame 62 by stitching or an adhesive means, and the frame 62 may be formed of a plastics material and may be shaped to fit around a carrier insert. The filter 50 may have carrier engagement portion(s), if so the carrier plate also comprises corresponding filter engagement portion(s) which are engageable with the carrier engagement portion(s). The carrier engagement portion(s) may be protrusion(s) in the form of a shaped corner portion, and the frame 62 may be shaped to fit into these raised corner portions. The first carrier portion may comprise a carrier insert shaped to fit within the carrier border 58 and to extend above the carrier border 58. The first carrier portion 56 may be raised above the carrier border 58. The assembly may comprise a former insert and second filter which engages the frame inner periphery and is held in place through an interference fit.