Use a jigsaw to cut out a square hole. Then use a jigsaw to cut the corners. Use a pencil, a framing square and a scale to draw the exact size of square you are looking for.
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Woodworking Cutting Square Holes ofwoodworking
How to do it position the tip of the chisel on a corner of the square you’ve drawn tap on the chisel with a sledgehammer as hard as possible keep tapping until it cuts through the entire wood thickness repeat the above steps for each corner cut the square out
To cut a square hole in wood, you need to follow these two steps.
