Method for manufacturing a recess plate

A method for manufacturing a recess plate to be used in a filter device for filtering a suspension, the filter device having a stationary head piece and a movable end piece, and a pack including copies of the recess plate, having a filter chamber inside the pack, adjoining the recess plate, having a first pipe for filling the suspension into the filter chamber, having a filter cloth for collecting a solid content out of the suspension, and having a second pipe for discharging a liquid fraction of the suspension out of the filter chamber as a filtrate, wherein the filter device may be closed before filtering by forcing the end piece in direction of the head piece, and opened after filtering by releasing the end piece, and moving the end piece away from the head piece for removing the filter cake from the filter cloth, wherein

• a. a first sheet is formed to provide a first surface of the recess plate at the filter chamber, and a second sheet is formed to provide a second surface of the recess plate vis-à-vis the first surface,
• b. a foam is injected into a spacing between the first sheet and the second sheet, and
• c. after hardening of the foam, the spacing is filled by a rigid body,
• d. the first sheet and the second sheet are mounted to a frame, wherein the frame contains all drills and bores required for the filtrate, and
• e. the foam, together with the frame, forms the rigid body.