Abstract: A portable straight edge cutting guide for use with a router, circular saw, sabre saw and similar tools, including a hardwood straight edge and metal angle iron track assembly with adjustable clamps for mounting on a work surface, a removable bearing block assembly having three cam follower bearings which engage with and travel along said angle iron track, and interchangeable adapter plates secured to the bearing block assembly, conforming to the particular tool, which fasten to and travel with the bearing block assembly. A router or other tool is mounted on the appropriate adapter plate; its position relative to the workpiece is aligned by means of adjusting screws on the bearing block assembly, and is then guided along the length of the work piece by the manual movement of the bearing block along the track.