Monster Square



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  • Monster Square
  • Monster Square
  • Monster Square
  • Monster Square
  • Monster Square
  • Monster Square
Frequently bought together:


The original Monster Square is available in a 12 or 8 inch size with two material choices: Cast Iron (FE) or Cast Aluminum (AL). All Monster Squares feature a stiff “flange and web” design that is fully machined on all outer edges with tapped holes on the sides for mounting tabs.

Made in USA, Patent Pending.


The Monster Square is designed to quickly set your workpiece to 90 or 45 degrees. Speed squares and machinist squares are made for visual inspection and checking AFTER setup, the Monster Square is designed to get those parts square in the first place.

Tabs help eliminate twisting and warping in the final workpiece. Once you have your workpieces square with each other don’t rely on the table, floor, or workpiece to get your work fitted to a flat plane. The machined squares and tabs always create the perfect plane for your workpieces to rest on. Bonus: The tabs also let you easily hold round tubing.

Clamping is simple with multiple surfaces for quick and rigid attachment. Stop spending your time and focus figuring out clamping strategies, or worse, clamping your straight workpiece to crooked surfaces.

Use the radius on the tabs to use the Monster Square as a traditional speed square for layout.

Square Size:

  • 2 inch tubing and smaller, we suggest 8” squares (1.5” wide)
  • 2 inch tubing and larger, we suggest 12” squares (3” wide)

Material Selection:

  • Cast Iron has excellent resistance to deformation and raising burrs when scratched, with the added benefit of some natural resistance to weld spatter.
  • Cast aluminum is lightweight and exhibits resistance to deformation vs aluminum billet. Its non-ferrous properties, resistance to weld spatter, and compatibility to sensitive surfaces are also more advantageous for certain types of work.

Differences between 12" and 8" models:

  • 12” squares have a profile similar to an I Beam where the web is centered on the flanges.  8” squares are similar to a “C” channel where the web is off to one side of the flange.
  • 12” squares have tapped holes on both sides, 8” only on the “back” or flat side

Monster 12

Monster 8

Model Size (in) Weight (lbs) Material Thread Size

Monster 12 FE

12 x 12 x 3


Cast Iron


Monster 12 AL

12 x 12 x 3


Cast Aluminum


Monster 8 FE

8 x 8 x 1.5


Cast Iron


Monster 8 AL

8 x 8 x 1.5


Cast Aluminum



What comes with each square:

Each square comes with 4 tabs (steel or aluminum to match square material type) and 4x socket head cap screws.  Each tab is 2.75" x 1" in size.   

More About Edge Location Tabs


What is Black Oxide?


Black Oxide, blackening, oxidizing, oxiding, black passivating, gun bluing . . . these terms all refer to the process of forming a black iron oxide on the surface of ferrous metals.


The black oxide process is a chemical conversion coating. This means that the black oxide is not deposited on the surface of the substrate like nickel or zinc electroplating. Instead, the black oxide coating is produced by a chemical reaction between the iron on the surface of the ferrous metal and the oxidizing salts present in the black oxide solution. These oxidizing salts include penetrates, catalysts, activators and proprietary additives which all take part in the chemical reaction. The result of this chemical reaction is the formation of black iron oxide, magnetite (Fe3O4), on the surface of the metal being coated. Black oxide has a range of unique properties and benefits including corrosion protection & reduced friction.


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