Empire Level Rafter square

[Lee Schierer]

Can anyone identify the purpose of the circled cut out in this Empire Levels rafter square. It isn't identified in the instructions. 399772

[Tim Bueler]

The slot is @ 3.5". Used for scribing a parallel line.

[Mike Cutler]

Lee
I'm no expert on speed squares, but I believe that cut out is used to square to an already established line.
If an already establish, drawn line, is aligned along the edge of that cutout, the edge of the speed square will be 90 degrees to that line, and can thus be marked. I think mine has a diamond,and not that trapezoid shape, but it's in the same place on my speed square.
They're a complicated little tool for a piece of stamped aluminum. Every time I need to use one, I have to watch a few Youtube videos.:o

[glenn bradley]

Features: 1/4 in. spaced scribing notches and the Diamond® cutout for easy rafter seat cuts and scribing the most common and popular stud widths.

[Lee Schierer]

I believe you are correct. It serves the same purpose as the diamond on a Swanson.

[johnny means]

Picture is worth a thousand words.