Empire 7" Aluminum Heavy Duty Rafter Square: The Fat Boy That Actually Works

Here’s what nobody tells you about rafter squares: the cheap ones flex. You press them against a 2x6, mark your line, and that aluminum blade bows just enough to throw your cut off by a blade width. Do that on every rafter, and your roof line looks drunk by the time you’re done.

Empire’s 2990 “Fat Boy” series solves this with a beam profile that won’t flex under pressure. The 7-inch aircraft-grade aluminum construction gives you the rigidity of steel at a third of the weight. Not revolutionary. Just solid engineering that works.

What Makes the Fat Boy Different

The extra-wide heel—that’s the Fat Boy profile—sits stable on lumber without rocking. Most 7-inch squares have skinny heels that tip when you’re trying to mark a bevel cut on rough-sawn lumber. This one plants itself and stays put.

Empire offers two marking options: laser-etched on the True Blue version or stamped on the standard Magnum. The laser etching costs more but won’t fill with sawdust or wear off after a thousand job sites. Your call on whether that matters for your work.

Accuracy runs about 1/8 inch tolerance—standard for aluminum squares in this size. Good enough for framing. Not good enough for finish work, but that’s not what a 7-inch square is for anyway.

Specification	Value
Size	7 inches
Material	Aircraft-grade aluminum
Profile	Heavy-duty beam style (Fat Boy)
Model	2990
Markings	Laser-etched (True Blue) or stamped (standard Magnum)
Accuracy	~1/8 inch tolerance

Where It Earns Its Keep

This square handles the standard carpentry tasks: roof rafter layout, ceiling joist layout, stair stringer layout, general framing, checking 45° and 90° angles, and serving as a saw guide for crosscuts.

The thick edge matters when you’re using it as a saw guide. Thin squares let the saw base ride up and ruin your cut. This one’s thick edge keeps your circular saw tracking straight.

Standard usage: place the pivot point at the edge of the board, align the desired angle on the ‘Common’ or ‘Hip-Val’ scales with the board edge, and mark along the blade. Used as a saw guide by pressing the wide heel against the board edge.

The Bottom Line

With 63 reviews on Zoro showing high engagement, contractors are buying these. The Fat Boy profile isn’t marketing fluff—it’s a functional design that addresses the main failure point of standard rafter squares: flex and instability.

Skip it if you’re doing finish carpentry or need dead-on accuracy. A 7-inch square with 1/8-inch tolerance won’t cut it for cabinet work. But for framing, roofing, and general carpentry where you need quick, reliable layout marks that won’t drift, the 2990 delivers what Empire promises.

The corrosion-resistant aluminum construction means it’ll survive Montana weather without rusting like steel squares do. Leave it in your truck bed through a spring rain, and it’ll still work Monday morning.

Frequently Asked Questions

Q: What’s the actual difference between the True Blue and standard Magnum versions?

A: The True Blue has laser-etched markings while the standard Magnum uses stamped markings. Laser etching won’t fill with sawdust or wear off over time, but stamped markings work fine if you keep the square reasonably clean.

Q: Can this replace a framing square for rafter cuts?

A: For basic common and hip rafters, yes. You align the desired angle on the ‘Common’ or ‘Hip-Val’ scales with the board edge and mark your cut. For complex compound cuts or full rafter layout, you’ll still want a traditional framing square.

Q: How does the Fat Boy profile actually help on the job?

A: The extra-wide heel provides stability on lumber, especially on rough or warped boards where standard squares rock back and forth. It’s the difference between marking once and marking three times because your square kept slipping.

Q: Is aircraft-grade aluminum just marketing?

A: The 2990 uses aircraft-grade aluminum, which typically means 6061-T6 alloy. It’s legitimately stronger and more rigid than standard aluminum, resisting the flex that throws off your marks.