Circular Saw Cutting Guide
Using a circular saw to crosscut a 4×4 post is a common operation. To cut all the way through the post, you have to make two passes. This often leaves a small ridge of material on the end of the post where the cuts aren’t aligned.
To create a clean, accurate cut, I use a shop-made guide. Basically, it’s a U-shaped “saddle” that clamps to the post (Photo, right). Two fences, one on each side, guide the saw to ensure perfectly aligned cuts. These fences allow you to make either 45° or 90° cuts.
The cutting guide consists of two sides (A), a back (B), and two identical fences (C), each with a 90° and a 45° edge. Start with extra-long pieces for the sides and back. They’ll be trimmed to length later with the circular saw, forming reference edges that will be used to position the guide on a workpiece. Carefully lay out the locations of the fences on each side of the guide so they align with each other. Then attach the fences and trim the waste with a circular saw to create the reference edges.
To use the guide, align the appropriate reference edge with a layout line on the post, clamp the guide, and make a cut. Then, without removing the guide, turn the post over and make a final pass on the opposite side.
Online Editor, Workbench