Abstract: A method of forming relief in a surface of a sheet utilizing a forming platen whose relief can readily be changed and an apparatus for forming relief in a surface of a sheet incorporating a platen whose relief can readily be controlled and varied on a real time basis, preferably, with piezoelectric actuators reciprocally driving small pixel elements into the surface of the sheet. The method involves using a first platen which carries an input relief. The first platen is to be urged into contact with a surface of a sheet such that the input relief on the first platen forms an output relief in the surface of the sheet corresponding to the input relief.

Abstract: An improved vented drain insert for insertion into a larger diameter drain pipe, preferably, a roof drain pipe. The insert has a tubular portion which extends into the drain pipe forming an annular restriction in the primary passageway through the drain pipe. A vent tube is provided to provide a secondary passageway from above the inlet to the drain past the annular restriction to the drain pipe below the drain insert. The vent tube is believed to be advantageously vent air and/or equalize pressures below the drain insert under flow conditions in the drain pipe in which air is present in the drain pipe.