Abstract: Toothed cutting blades are made by forming spaced slots in an edge of a blade preform (20) to leave lands (8) between leading and trailing walls (4, 6) defining the slots, the leading walls (4) having a rake angle greater than that required in the finished blade, and the lands having aligned top surfaces between the slots, and then applying bending forces to the lands (8) so as to reduce the rake angle of the front walls to that desired and incline the top surfaces to form positively raked teeth with inclined back surfaces (32). The lands may be bent by tools inserted in the slots, or by compressing their material between punches applied adjacent their front walls.

Abstract: The present invention is a plumbing device for buildings that installs inline with a drainpipe to separates large solids component of wastewater from small solids and liquid components of said wastewater, thereby creating two separate output streams. The second stream of mostly liquid can be directed first to a heat exchanger and then to a sewer or wastewater recycling device.

Abstract: The present invention is an apparatus and system to recover heat from wastewater in a new or existing building comprising a convector heat exchanger with thermal storage that accepts wastewater of any temperature, an in-line separator to direct large solids away from the heat exchanger, a process to create turbulent flow in the tubing from which the heat exchanger is made, an automatically switched vibration base to improve heat transfer, an automatic flush system for the wastewater heat exchanger and a method of installation in slab-built buildings.

Abstract: There is provided a method for treating a surface which is to be bonded to another surface, the method comprising displacing a portion of the surface material to a position such that the displaced material, while remaining an integral part of the surface, forms a burr which is adapted to mechanically engage a flexible material placed adjacent thereto to thereby provide a mechanical interlocking action.

Abstract: The invention relates to a holder comprising a frame fitted with compressible elements to provide a unique side holding force to releasably retain a note pad of the removable, self-stick variety. The side holding force is proportional to the total thickness of the material being held and allows access to the full face of the note pad surface. The side holding force and the additional benefits of material protection and widespread mountability, provides the user with access to the note pad wherever and whenever required.