When you're cutting plywood, sometimes the blade catches the veneer and rips it unevenly, causing "tear out". Tear out marks will ruin the look of your project, but can prevent them with a simple trick.
First, make sure to always cut plywood with the best side facing down, so the blade won't mark it cutting up through the wood. Tear out occurs when the blade exits the top side of the wood and catches the veneer.
To prevent this from happening, apply masking tape to the top side of the wood that will be cut. Then remove the tape to reveal a cleanly cut edge. The video above demonstrates this tip with painter's tape. It's more expensive than masking tape, but both will work just as well.
Preventing Tear Out When Crosscutting Plywood [Make Something (YouTube)]
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