Johnson Rafter Angle Square

I recently learned that what I’ve always called a Johnson Rafter Angle Square is officially called a Johnson 7 Inch Johnny Square. The Johnny Square was named after Johnny Wong a builder and carpenter who helped test and develop the square in the field.

As long as I can remember I’ve always owned and carried a Johnson Rafter Angle Square in my tool belt. As a carpenter and builder the Johnson Rafter Angle Square or Johnny Square is the first square I reach for and I end up using it for 99% of my squaring lines, square cutting and line and angle marking applications.

The Johnson Rafter Angle Square allows me to make fast, efficient and accurate measurements and cuts.

For information on usage, see our guides on how to read a rafter angle square and how to use a rafter angle square.

Johnson 7 Inch Johnny Square New Features:

The new Johnny Square has a continuous 1/8 inch scribing grooves [from 1 inch to 5-1/2 inches] that will very likely prove to be a huge addition to an already useful, "go-to" tool.

I use the rafter angle square to mark long rip lines all the time and sometimes the pencil slips. Now with the scribing grooves I can make these lines faster and more accurately.

Like the older version the new Johhny Square has an easy to read angle scale from 0 to 180 degrees. The one number layout for roofs, solar panel supports, stairs and trim is useful and fast to utilize. A small booklet comes with the square showing how to use these scales and illustrate basic rafter and angle layout information.

Johnson 7 Inch Johnny Square

  • Solid aluminum body with CNC machined edges for greater accuracy and durability
  • Permanent graduations and numbers are easy to read
  • Thick edge is useful as a saw guide
  • Continuous scribing notches – ideal for ripping at 3-1/2” and 5-1/2”
  • Low-glare, protective powder coated finish
  • Complete instruction manual included with rafter tables (RAS-1 & 1941-0700)