Mega Square

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  • Mega Square, 12 Inches, Cast Iron
  • Mega Square, 12 Inches, In Use
  • Mega Square
  • Mega Square
  • Mega Square
Frequently bought together:


The original Mega Square is available in a 12 or 8 inch size with two material choices: Cast Iron (FE) or Cast Aluminum (AL). All Mega 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

Roomy joint access for welding, gluing, nailing, riveting, etc.

Whatever process you’re working with, it probably benefits from some clearance around the joint.

Tabs help eliminate twisting and warping in the final work-piece.

The machined squares and tabs always create the perfect plane for your work-pieces to rest on. 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.

Perfect For Angle Iron

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

Flange & Web

  • 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.
Customer Reviews

"Awesome squares. I also ordered the extra tabs. I use them constantly as my worksuraces are all slightly bent. These squares fix that as it's the contact with the material and the squares that render the work surface defects moot! I will be buying more possibly the minions but definently the angle squares I really need those. I'm an artist so I get crazy angle request."

Alma L.
"I've been fabing a few years now, and just recently started to do bigger projects, and haven't made the investment into a proper fab table yet. And I can tell you this is must have if you don't have a fixture table. But the great thing about fireballs squares are that if you do a Fab table then these are great addition to it! You can start with these at a lower entrance fee and make more money with better quality and increased production speed, and then get your table and continue to use them with even greater versatility. I picked up a 12" aluminum Mega Square, and I'm already planning on getting the 12" Monster Square. And I personally went with the 12" over the 8" because the larger squares are able to work on smaller projects as well as the big ones."
Earl K.


Mega Square 12"

For tubing 2 inch and larger, we suggest 12” squares (3” wide)

Mega Square 8"

For tubing 2 inch and smaller, we suggest 8” squares (1.5” wide)

Size (in) Weight (lbs) Material Flange (in)

Mega 12" FE

12" x 12" x 3"


Cast Iron


Mega 12" AL

12" x 12" x 3"


Cast Aluminum


Mega 8" FE

8" x 8" x 1.5"


Cast Iron


Mega 8" AL

8" x 8" x 1.5"


Cast Aluminum


Aluminum vs Cast Iron

Cast Iron


  • Great for heavy duty projects
  • Excellent resistance to deformation and raising burrs when scratched.
  • Some natural resistance to weld spatter.


  • Heavy (Not ideal for mobile welding)
  • Susceptible to rust.



  • Lightweight (Ideal for welding on the go)
  • Resistance to deformation vs aluminum billet
  • Some natural resistance to weld spatter.


  • Can be be damaged if dropped or if used in heavy duty projects.

New Dragon Scale

Fireball’s new Dragon Scale coating provides the corrosion resistance of our previous black oxide finish with the added benefit of enhanced spatter resistance. It’s spatter resistance needs to be seen to believed; it out performs even the best weld spatter sprays without the use of any sprays.

Included Accessories

4 Edge Location Tabs

Our revolutionary tabs allow you to align your material up so that you don’t even need a welding table! Don’t spend thousands on a flat table, just use our squares! Tighten the tabs onto the front or back of your square and you can immediately get to work. Sure, there are different jigs out there, but can they line your material perfectly in seconds?

4 Tool-less Thumbscrews

But it doesn’t stop there. We reinvented the game by introducing our thumbscrews. Say goodbye to your hex keys and Allen screwdrivers and freely adjust the tabs with only your fingers!

Optional Add-ons

Edge Alignment Pins

Install our edge alignment pins on any square to create a large, overhanging edge which can be used to index the square on a different plane. Depending on the square, this allows you to create edges which are 90 degrees (perpendicular), 45 degrees, parallel, and even 60 and 30 degrees from the edge.

  • Use it with our Monster squares to create a speed square for layout.
  • Use it to hang the square off the edge of a table for working vertical or perpendicular to table surface
  • Use it to elevate the squares off the ground or table for extra clearance when you’re fitting and welding entire frames
  • Tip! If trying to create a parallel edge with the mega square for marking, use our shims to get that perfect distance!

Our Other Squares

  • The original Monster Square is available in a 12 or 8 inch size with two material choices.
  • The Monster Square is designed to quickly set your work piece to 90 or 45 degrees.
  • Clamping is simple with multiple surfaces for quick and rigid attachment.
  • Use the radius on the tabs to use the Monster Square as a traditional speed square for layout.
  • Use it as an ordinary, adjustable angle square that adjusts from 40 to 180 degrees.
  • Right Angle 90 Degree Square with generous weld accessibility. Total height of 8” in this configuration.
  • Tall 12” square when fully opened and locked into place
  • Remove the fasteners to get two individual squares
  • Use the large V-groove to hold large round tubing or pipe
  • Compact configuration for use in tight spaces.
  • 6" x 4" x 1.5", the 4" width is perfect for picket spacing on gates and fences.
  • They are the first square we offer which has a built in 60/30 degree angle.
  • The cutout provides just the right amount of joint access when using it to clamp things at 90 degrees.  

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78 Reviews

  • 4
    Solide, accuracy not verified as of yet

    Posted by Steph on Jan 21st 2022

    If you can, get dragon scale. When received the cast iron non dragon scale cause it wasn't available, lots of rust spots had already set on it upon arrival. Old stock laying around? Spent 1/2 day cleaning rust off. Will be treating with blue gun.

  • 5
    Mega sq.

    Posted by Carl Ventresca on Jan 7th 2022

    Top.of the line product.

  • 3
    8in square

    Posted by Kyle on Jan 4th 2022

    Product came very sharp covered in chips and dirt, could greatly benefit from more post processing. I notice there is some deburr work but it isn't enough. I can stack two squares on top of each other and they will rock back and forth, not inspiring for what I hoped to be a premium product.

  • 4
    Love the coating it should last for years

    Posted by Lance Jagos on Jan 1st 2022


  • 4
    Love the coating it should last for years

    Posted by Lance Jagos on Jan 1st 2022


  • 5
    Awesome Mega Squares

    Posted by Eric Hoskins on Dec 23rd 2021

    Amazing squaring tools. Easy to use and makes fitting up projects go smoothly and quicker

  • 5

    Posted by RON KAUFMANN on Dec 21st 2021

    Excellent workmanship

  • 5
    Mega square

    Posted by Ken King on Dec 15th 2021

    Excellent product

  • 4

    Posted by Mathieu on Dec 14th 2021


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