Starrett Protractor Head Value Guide

The L.S. Starrett Protractor Head is a cornerstone of American industrial precision, originating from Athol, Massachusetts, between 1900 and 1940. As a vital component of Laroy S. Starrett's revolutionary combination square system, these cast iron tools are highly sought after by modern craftsmen for their enduring accuracy and historical significance.

What Is Starrett Protractor Head Worth?

The typical price range for Starrett Protractor Head is $25 - $40 based on recent sales. However, values can vary depending on the item's condition, rarity, and other factors such as:

• Condition of the locking nut and the smoothness of the rotating turret mechanism.
• Presence of the original scribe tool, which is frequently missing from vintage units.
• Clarity and legibility of the etched degree markings on the steel scale.
• Overall state of the cast iron finish, with higher value placed on pieces with minimal rust or pitting.

How to Identify Starrett Protractor Head?

• Look for the 'L.S. Starrett Co.' maker's mark stamped clearly into the cast iron body.
• Verify the presence of the original spirit level vial, which should be intact and functional.
• Check for the characteristic black crinkle or smooth japanned finish common on early 20th-century models.
• Ensure the protractor scale features crisp, deeply etched degree graduations from 0 to 180.

History of Starrett Protractor Head

The L.S. Starrett Company, founded in 1880 in Athol, Massachusetts, quickly became a leading manufacturer of precision tools. Laroy S. Starrett's innovations, including the combination square and various calipers, revolutionized accuracy in mechanical work. This protractor head is a component of Starrett's renowned combination square system, highly valued by machinists and craftsmen for its versatility and precision.