Abstract: A machine for manufacturing "sleuters" or other articles of folded plasterboard is described. Sleuters are employed as spacers or risers between stacks of plasterboard or other sheet material and have the advantage that they do not physically mark or discolor such plasterboard, as conventional wooden sleuters sometimes do. Plasterboard remnants are cut to a standard length, and then conveyed intermittently between work stations where they are scored to provide fold lines, folded into two pleated members while simultaneously breaking such members apart from each other, and then stapled. The folding apparatus includes upper and lower folding arms which are moved toward the plasterboard and pivoted to fold and break such board into the two pleated members. The pleated plasterboard members are transmitted from the folding section through a guide to compress them while their layers are stapled together to form the completed sleuter.