Johnson 7 Inch Johnny Square

Johnson Rafter Angle “Speed Square”

speed square

I recently learned that what I’ve always called a Johnson Speed 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 Speed Square in my tool belt.  As a carpenter and builder the Johnson Speed Square or Johnny Square is the first square I reach for and I end up using it for 99 percent of my squaring lines, square cutting and line and angle marking applications.

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

Johnson 7 Inch Johnny Square New Features:speed square

The new Johnny Square has a continuous 1/8 inch scribing grooves [from 1inch 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 speed 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)

About the author

Rob Robillard

Robert Robillard is a remodeler, general contractor, and principal of a carpentry and renovation business located in Concord, Massachusetts, and serves as the Editor of Tool Box Buzz and founding editor of A Concord Carpenter . Rob is in charge of our Tool and Product Review - Tool and Product Review - Video Channel, , where we post all of our tool reviews and video tutorials. Rob enjoys using his knowledge and experience to help and educate building professionals as well as DIYers on best practices in the remodeling industry. The Concord Carpenter's motto: "Well done is better than well said!" : Read more about Rob Robillard

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  1. Jeff Williams

    Is that a “church key” in the middle of that thing?

    1. Yes it is. I purposely did not mention it because I feel it too closely connects opening beer bottles and power tools. Two things that should never mix.

      1. Jeff Williams

        It seems an odd addition considering the sheer number of tools on a job site that can open a beer bottle. I’m right there with you, the beer doesn’t come out until all the tools are put away.

      2. Todd Fratzel

        On the other hand….great gift for a bar tender that serves the local builders!

  2. Jeff Williams

    Another great feature of this tool is that it’s made right here in the USA.

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