What device is commonly used to set a grade line during excavation?

The device commonly used to set a grade line during excavation is the stringline. A stringline consists of a taut line stretched between stakes at either end of the area being excavated, providing a clear visual reference for establishing the desired grade across the site. It is particularly useful because it can be easily adjusted and moved as work progresses, allowing for precise alignment with the required elevations.

While other tools like laser levels might offer advanced accuracy for certain applications, they are typically used in more specific contexts or for longer distances. Leveling rods are instruments that facilitate the determination of levels but do not set the grade line themselves. Surveyor's chains are primarily used for measuring distances rather than setting grades. Therefore, for the particular task of establishing a consistent and precise grade line during excavation, a stringline is the most practical and effective choice.