Abstract: An adjustable radial curve radius setting scale is provided having an end supporting bar to which there is attached an assemblage of stacked elements. The stacked elements comprise a first level radial arm having connecting dowels, second and third level long chords are attached to the radial arms. Second and third level diagonal braces are attached to the first level radial arms. Fourth level diagonal braces are attached to the first level radial arms and fifth and sixth level brace chords are attached to the fourth level diagonal braces. The seventh level radial arms have outer guide pins and inner raised bosses with apertures to received the dowels of the lower radial arms. The assemblage is snap-fitted together by means of an O-ring on the dowels of the first radial arms. The assemblage is free to rotate to form a curve of any desired radii. At least one working edge is secured between the first and seventh radial arms and may be locked in a given pre-set radius by a latching mechanism.

Abstract: An adjustable radial curve radius setting scale is provided having an end supporting bar to which there is attached an assemblage of stacked elements. The stacked elements are fastened together by pin assemblies so that they move independently of each other. The stacked elements are attached to the supporting bar and are adjustable relative thereto. A ruling edge is attached to the stacked elements for creating a curve upon manipulation of the stacked elements. A bar scale is attached to the supporting bar and to the stacked elements so that the user of the instrument may set or determine the exact radius of a curve created by the instrument. The bar scale may be removable by the provision of a locking device which would function to lock the ruling edge to the ruling arm assembly. A base having at least one guideway is provided for the radial curve whereby radii of particular dimensions may be constructed. A transparent cover is provided for the base.

Abstract: An adjustable radial curve is provided having an end tangent bar to which there is attached an assemblage of stacked elements. The stacked elements are fastened together by pin assemblies so that they move independently of each other. The stacked elements are attached to the tangent bar and are adjustable relative thereto. A ruling edge is attached to the stacked elements for creating a curve upon manipulation of the stacked elements. A barscale is attached to the tangent bar and to the stacked elements so that the user of the instrument may set or determine the exact radius of a curve created by the instrument. The barscale may be removable by the provision of a locking device which would function to lock the ruling edge to the ruling arm assembly. A base having at least one guideway is provided for the radial curve whereby radii of particular dimensions may be constructed. A transparent cover is provided for the base.