Double Square Basics

The basics of precision double squares. This tool has a few functions, but primarily checking squareness or measuring/marking from an edge Become a patron:   / justtoolbasics   Affiliate product links: Starrett 4" precision double square (shown): https://amzn.to/3kjskug Similar (and much more affordable) 4" double square: https://amzn.to/3piLunI