Build this saw track jig from scrap plywood in less than 30 minutes
Unlike single-guide jigs, this saw track jig has guides on both sides to keep the saw from wandering to either side of the line. You don’t need to modify your circular saw in any way, and the sight-holes make it easy to align the blade path with your cut line.
You can build it from scrap plywood in less than 30 minutes. The jig shown here is designed to make cuts just over 4 feet long, but it can be adapted for longer cuts.
--This video appears on Tommy Rich's website, One Minute Workbench, which is dedicated to woodworkers who don’t have the luxury of a full-size shop. It includes videos and plans for tool storage, carts, work tables, and other elements for building a full workshop in limited space using compact designs that can be ready for use in less than one minute.