of a bar that has sliding adjustable clamps that secure a cable which go around pulleys on a router or other cutting device that when the cable is pulled taut creates a path for the router or other cutting device to follow while it cuts thus cutting an arch into the work piece prior to this apparatus one would have to cut this arch with a template which had been previously tooled this jig apparatus creates a template and cut all in one step application_number US 51956400 A description the following description of the preferred embodiment of the invention is not to be taken in a limiting sense but is made merely for the purpose of illustrating the general principles of the invention the following detailed description is a suitably contemplated mode of carrying out the present invention the spirit of the concept of this jig apparatus may be expressed in ways not mentioned here one must interpret by an overall assesment with reference now to the drawings and particularly to fig1 the arch cutting jig apparatus is comprised of a bar 14 wooden or aluminum having a slot 13 see fig3 which receives a sliding clamp 12 there are two sliding clamps 12 one on either side of the length wise center point 19 fig2 of the.