One issue that quickly pops up when using full sheets of plywood is how to break it down to manageable pieces. One of the more accurate and easier methods would be to use a track saw. The problem for most of us is that track saws are expensive. So, a good alternative method is to use some sort of straight edge to guide your circular saw. This can be done with any straight edge whether it is a long level, another piece of lumber, or a dedicated jig.
The benefit of making a jig, or guide, for your circular saw is that it will be reliable, and you can create a zero-clearance line to make it easier to line up your cuts. There are many ways to make a circular saw guide, but my preference is for simplicity and function. I recommend having a few different lengths for your guides. This way when you only need to do a shorter cut, you don’t have to move around an 8-foot-long guide.
The basics are a flat piece of plywood to run the circular saw on, a guide piece attached to the top to ensure a straight cut, and some space to clamp the guide down. You could also add an extra piece under the guide to help make cuts square, but for me, measuring carefully is sufficient.
I have a video that shows the build of my guide available on YouTube as well as free downloadable plans to help build your own guides.
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