Abstract: An adjustable carpenters square has a handle and first and second blades extending from the handle in a substantially perpendicular relationship. The first blade is fixed in the handle and the second blade is pivotally mounted on the handle to enable it to be adjustable with respect to the fixed first blade to ensure that it is at a true 90° to the first blade. A cam mechanism is mounted in the handle and engageable with the second blade to pivot the second blade with respect to the first blade. The cam mechanism includes a one-piece cam having a cylindrical base and a cam portion offset therefrom. This cam mechanism enables the method of the present invention of adjusting the perpendicular relationship between the two blades to be achieved with a high degree of accuracy.

Abstract: The invention is a system for measuring the true dimensions and orientation of objects in a two dimensional image. The system is comprised of a ruler comprising at least one set of features each comprised of two or more markers that are identifiable in the image and having a known spatial relationship between them and a software package comprising programs that allow extension of the ruler and other objects in the two dimensional image beyond their physical dimensions or shape. The system can be used together with radiographic imagery means, processing means, and display means to take x-ray images and to measure the true dimensions and orientation of objects and to aid in the identification and location of a surgery tool vs. anatomy in those x-ray images. The invention provides a method of drawing and displaying on a two dimensional x-ray image measurements of objects visible in said image, graphical information, or templates of surgical devices.

Abstract: A precision machinist's square comprises a blade and body joined together at a pivot and a drive train operated by relative angular movement between the blade and the body. Movement of the drive train develops a movement in a dial indicator that is a function of the angle between the body and the blade.

Abstract: A universal squaring jig which may be used when welding various workpieces in perpendicular orientation. The squaring jig has two workpiece holders attached together by one or more support members. Each holder has three mating surfaces. The first and second mating surfaces together form a perpendicular interior corner. The first and third mating surfaces form a perpendicular exterior corner. Magnets are placed on both the first and third mating surfaces to hold workpieces in mating contact with the surfaces of the squaring jig during welding.

Abstract: A square holding a laser device for transmitting a laser beam to generate straight lines from the square to the surface upon which the laser beam impinges.

Abstract: A golfer's square includes a ball position pointer or the like. The ball position pointer includes an elongate substantially parallel-sided pivotable rule with a pivot end and a pointer distal to the pivot end, and the ball position pointer or the like is rightly attached to an elongate substantially parallel-sided right rule attachable to the pivotable rule, with hook and loop material such as VELCRO (Reg. U.S. Pat. & Tm. Off.), to make the golfer's square. The golfer's square or the ball position pointer may be used separately in methods to assist the golfer align his stance properly. A protruding right angle edge may be provided on the right rule to faciliate orienting both rules prior to attaching same together.

Abstract: By mounting a longitudinally extending blade with a mounting block for pivotal movement about an axis perpendicular to the longitudinal axis of the blade, in combination with a distance measuring meter mounted to measuring engagement with the movable blade, a precision squareness measuring gauge assembly is achieved for providing highly accurate measurements of the angular relationship of one surface to a reference surface. In the preferred embodiment, the precision measuring gauge assembly also incorporates pivot limiting means for controlling the arcuate distance through which the blade is able to pivot. In this way, the entire arcuate travel distance of the blade is accurately measured and displayed on the meter, thereby providing a direct accurate measurement of any desired surfaces.

Abstract: A square for glass cutting has a triangular shaped phenolic plastic body having a head supporting base member, a straight edge, and a straight edge strengthening member. The base member has a plurality of apertures having diameters of a first dimension. A head member includes first and second head plates interconnected and spaced by a bridge to sandwich the base member. The first and second plates have a plurality of apertures having centers corresponding to the centers of the base member apertures, but having diameters of a second dimension less than the first dimension but equal to the diameters of set screws, whereby when the head member is loosely attached to the head support member by the set screws the squaring of the first head plate automatically squares the second head plate and the tightening of the set screws maintains the squared relationship between the head plates and the straight edge member.