Mark Cut Line with Framing Square

What happens here

Once the lumber is stacked and aligned, the carpenter places a framing square (or speed square, though a larger framing square is ideal for wide stacks) across the top face of the outermost board, ensuring the square's edge creates a perpendicular line to the length of the boards. A marking tool, such as a carpenter's pencil, is then used to draw a clear line along the square's edge, transferring this precise mark to all stacked boards. This line indicates where the gang-cut will be made.

Goal: Use a framing square or a speed square to establish a perfectly straight and square cut line across the top face of all stacked lumber pieces. This ensures consistency and accuracy for subsequent cuts.