Double Square, 6" 4R, Starrett
- Starrett 6" double square with graduated blade
- 4R Graduation – 8ths, 16ths, 32nds, 64ths
- Popular with machinists, toolmakers, and patternmakers
- The head is approximately 3-1/2" (90 mm) long
- The faces are approximately 9/16" (14 mm) wide
The sliding blades are adjustable making it more practical for a wide variety of uses than a common square with fixed blade. The faces of the head are ground square, and the 6" (150 mm) size has a level.
The beveled blade and the drill grinding blade shown at the bottom of the photo are not included with this product.
Starrett catalog number 13C.
Chris' Tips
When using a precision rule for very close accuracy, the eye can read better by measuring between two lines than from the end of the rule to a line. Here is how to use a steel rule.