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3 Ways to Make a Guide for a Circular Saw
1. Use a Board as a Straightedge
The first and most obvious way to create a guide is to clamp a board to the plywood and run the saw along the edge. The key is to use a wide board so that you can keep your clamps clear of the motor of the circular saw.
The downside of this method is that you have to account for the offset of the blade to the edge of the saw’s base, and it can take awhile to set up each time because you may need to make repeated adjustments to properly locate the board before making a cut.
2. Attach a Foot to a Board to Square the Cut
An easy way to upgrade this board, and number two on our list, is to attach a second board perpendicular to the straightedge—flush with it’s end.
Slide the added board against the back edge of the plywood to square up and make the cut. While you may skill need to clamp the guide place, it saves time by automatically squaring the straightedge to the plywood so you don’t have to make repeated adjustments.
3. Create a Custom Guide from Plywood
The create the third and most versatile guide trim 4 inches off a ¼-inch thick project panel. Glue the strip to the center of the panel, and then run the saw along both sides of the strip to trim the panel.
Now you can place the board along your line and without measuring, and make a cut on either side of the board.
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How to Make Straight Cuts with a Circular Saw | House One