In the second video, This Old House contributor Mark Clement shows how to set and maintain the bevel adjustment at 90 degrees specifically for cutting perpendicular to a surface. The slightest degree difference can create a significant error while cutting, so for a precise measurement it's helpful to manually check and correct the blade's relationship to the shoe of the saw.
Learn how to:
Set and maintain a 90-degree angle for a square cut
Properly measure and adjust the blade angle
Avoid making an error in cutting