A roof square for marking rafters comprising a right angle triangular body with a marking blade pivotally mounted adjacent the right angle. Either side of the square adjacent the right angle is held against the stock to be marked, and the blade used to mark either a plumb cut or a foot cut. The blade retracts to allow marks to be made at a measured depth. The tool can also be used as a conventional square to make 90 and 45 degree marks.

A device is provided for use with a reference tool during the construction of metal structures. The device comprises a body having a groove formed therein for receiving a portion of a straight side of the reference tool. The body further comprises a base surface for co-operating with the surface of a metal workpiece. The base surface is configured whereby, when a portion of the straight side is received within the groove, the base surface is parallel to the straight side of the reference tool. A retention assembly is mounted on the body for retaining the portion of the straight side of the reference tool, when provided, within the groove. At least one magnet is mounted on the base surface for temporarily holding the device to the metal workpiece, thereby holding the reference tool in position.

A hand layout tool, apparatus, and method directed toward skilled and industrial trades, or for use within other similar mechanical layout and user applications, is presented. The current invention allows the trades technician or user to quickly and accurately determine or otherwise identify the outer or inner centerline of a radial or cylindrical surface feature at a selected or desired angle. Alternately, the current invention can allow the user to quickly, easily, and accurately measure or otherwise determine the included angle between two imaginary planes: a first plane defined as being coincident with the central axis of the cylindrical or radial surface and a first point on an outer or inner cylindrical or radial surface and a second plane defined as being coincident with the central axis of the cylindrical or radial surface and a second point on an outer or inner cylindrical or radial surface.

A newly proposed articulating invention, each of whose four constituent embodiments is designed to trisect any of a multitude of suitably described angles by means of becoming properly set to its designated magnitude; thus automatically portraying a motion related solution for the trisection of an angle that discloses complete routing details of a pathway that leads from such designated magnitude all the way back to its trisector; thereby discerning the whereabouts of certain intersection points which evade detection when attempting to otherwise locate them by means of applying only a straightedge and compass to an angle of such designated magnitude; furthermore projecting finite lengths of any trisector that bears cubic irrational trigonometric properties, being those that cannot be duplicated, but only approximated, when applying a straightedge and compass to a given length of unity; and being of a unique design that could be adapted to function as a level.

A storage system where multiple containers having a plurality of vertical slots on all four internal sides for receiving dividers; one or more dividers that can be installed in various positions in the container, in either direction, and lock into place. Each divider has flexible tabs at either end, and each slot where a divider can be installed in the container includes an opening for this tab to lock into. A latch mechanism can be easily installed or removed on the container for locking multiple containers on top of each other when stacked. The latch mechanism can be installed on two opposing sides at the bottom of the container and locks into an edge on the top of another container. A lid that locks on top of the container and includes measuring features for components that may be stored in the container.

An adapter for a tripodal stereotactic reference frame for use in arthroplastic surgery mounts a third leg of the frame at an angle with respect to the other two legs to facilitate use of said frame with varying surgical exposures.

An apparatus for locating a hardware at a desired location on a tubular structure of a machine includes a linear element including a plurality of linear reference indicia thereon, a slider coupled to the linear element, an angular element including a plurality of angular reference indicia thereon, a hardware locator coupled to the linear element and adapted to engage with the hardware to locate the hardware at the desired location on the tubular structure, and a reference hardware locator coupled to the angular element. The angular element is coupled to the tubular structure such that the reference hardware locator engages with a pre-existing hardware mounted on the tubular structure. The pre-existing hardware is used as a reference to locate the hardware at the desired location on the tubular structure.

A staircase handrail support device removably connected to a staircase to facilitate installation of a handrail, the staircase handrail support device including a telescopic pole, a base connected to at least a portion of a first end of the telescopic pole to stabilize the telescopic pole on the staircase, a first miter gauge pivotally disposed on at least a portion of the first end of the telescopic pole to indicate a first angle of the telescopic pole with respect to the base, and a second miter gauge pivotally disposed on at least a portion of a second end of the telescopic pole to receive the handrail thereon and indicate a second angle of the telescopic pole with respect to the second miter gauge.

A measuring tool for determining angles at two points of interest, including an elongate arm and two protractors, one protractor rotatably mounted at each end of the arm. Each protractor includes a flat for positioning the protractor against one of the two points of interest. The angle at each point of interest is the angular measurement between the arm and the two flats, respectively. The arm may include two attachment sections, one each of the two attachment sections rotatably connected to one each of the two protractors, respectively, and an L-shaped guide having three connection points for selectively receiving and retaining the two attachment sections in various configurations as desired.

An educational ruler is a protractor, where the protractor can draw and measure angles. The educational ruler includes a planar disk having a semicircular circumference and labeled in scales along the semicircular circumference; a straight line edge connecting two edges of the semicircular circumference; a through hole on the planar disk; a first edge and a second edge extending from the through hole to the straight line edge; a third edge and a fourth edge extending from the semicircular circumference to the straight line edge. The first edge of the through hole of the educational ruler and the second edge of the through hole of the educational ruler intersect at 90 degrees scale of the planar disk to form the first right angle, and the included angle of the first edge of the through hole of the educational ruler and the straight line edge of the educational ruler is 45 degrees.