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.

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.

A tool that can be retained in a predetermined position relative to a workpiece and to perform an operation on the workpiece includes a head portion and a tail portion. The head portion includes a leg that is adapted to engage a first portion of a workpiece when the tool is in a predetermined position relative to the workpiece. The tail portion extends from the head portion and includes a support having a recess that is adapted to engage a second portion of the workpiece when the tool is in a predetermined position relative to the workpiece. An operation-performing device is supported on the tail portion and is operable to perform an operation on the workpiece when the tool is in the predetermined position relative to the workpiece.

A tool that can be retained in a predetermined position relative to a workpiece and to perform an operation on the workpiece includes a head portion and a tail portion. The head portion includes a leg that is adapted to engage a first portion of a workpiece when the tool is in a predetermined position relative to the workpiece. The tail portion extends from the head portion and includes a support having a recess that is adapted to engage a second portion of the workpiece when the tool is in a predetermined position relative to the workpiece. An operation-performing device is supported on the tail portion and is operable to perform an operation on the workpiece when the tool is in the predetermined position relative to the workpiece.

A ruler, steel square, combination square, try square, or the like has a surface partially or entirely covered with a polymeric film. The polymeric film has a writing surface upon which legible and erasable markings may be made with a standard graphite- or wax-based pencil.

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.

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.

A planar, T-shaped template member has a linear leg section with a first end thereof intersecting a cross bar section at a center thereof. The cross bar section has opposed ends, each end having a feature at a selected location therein. The cross bar section also has a circular aperture there through positioned opposite the leg section, with the circular aperture connected to an access channel extending to an edge of the cross bar section opposite the linear leg section. The linear leg section has a protrusion at a second end thereof opposite the cross bar section. The protrusion is sized to pivotally fit into the circular aperture and access channel of an identical T-shaped planar template member, thereby allowing pivotal movement between connected planar T-shaped template members. A large number of such templates can be connected together in a line.

A handwriting tool includes a paper holder having a writing surface, a longitudinal axis, an upper section, a lower section, and a plurality of spaced-apart line stations disposed parallel to the longitudinal axis. A writing guide is connected to the paper holder, the writing guide is slidably positionable along the longitudinal axis. The writing guide has a stop which is engagable with each line station of the plurality of spaced-apart line stations. The writing guide includes a transverse upper writing edge which is positionable in the upper section of the paper holder, and a transverse lower writing edge which is positionable in the lower section of the paper holder.