This tool functions as an accessory component for a standard machinist combination square set. When paired with a grooved steel rule, it forms a combination bevel protractor used to accurately measure, transfer, and lay out angles from 0 to 180 degrees in both directions.
Key Visual & Design Features
Material & Build: Cast from heavy-duty iron with a classic textured finish and precision ground reference flat surfaces on the bottom face.
Revolving Turret: Features a central rotating dial graduated in individual degrees. The twin lines of numbers allow reading opposing complementary angles cleanly.
Locking Mechanism: Equipped with a central knurled thumb-screw nut used to lock the protractor securely at a specific angle along the slot of a matching scale rule.
Level Vial: Includes an integrated spirit bubble level positioned right below the dial arc for leveling surfaces or taking angular reference readings relative to true horizontal.
embrace the quality that has stood the test of time.
Vintage Starrett Protractor Head 420 PR-1224 7" Round Measuring Tools Machinist love these old USA tools seem to last forever!!!
This tool functions as an accessory component for a standard machinist combination square set. When paired with a grooved steel rule, it forms a combination bevel protractor used to accurately measure, transfer, and lay out angles from 0 to 180 degrees in both directions.
Key Visual & Design Features
Material & Build: Cast from heavy-duty iron with a classic textured finish and precision ground reference flat surfaces on the bottom face.
Revolving Turret: Features a central rotating dial graduated in individual degrees. The twin lines of numbers allow reading opposing complementary angles cleanly.
Locking Mechanism: Equipped with a central knurled thumb-screw nut used to lock the protractor securely at a specific angle along the slot of a matching scale rule.
Level Vial: Includes an integrated spirit bubble level positioned right below the dial arc for leveling surfaces or taking angular reference readings relative to true horizontal.
embrace the quality that has stood the test of time. 082826