Crescent Lufkin Extendable Square Offers Pivotal New Feature
In another one of those โwhy didnโt I think of that and then retire?โ moments, the Crescent Lufkin extendable square is making us rethink what squares we carry. Essentially, itโs a 7-inch rafter square (or speed square, Swansonโs proprietary and super-common name for these) with a pivoting extension that reaches 12 inches.
Pros
- Size of a 7โณ square with the reach of a 12โณ
- Easy-to-read markings
- Scribe edges across the entire length
Cons
- The extension is at greater risk of bending or breaking than a full 12โณ square
Recommendation
The Crescent Lufkin extendable square has proven itself to be a very handy addition to our shop. Its size is more manageable than a 12-inch rafter square and itโs more versatile than a 6-inch or 7-inch speed square. If you use a rafter square frequently for professional or DIY use, give it a shot. We donโt think youโll be disappointed.
How Square is the Crescent Lufkin Extendable Square?
The basic design starts with an aluminum 7-inch rafter square and attaches a hinged extension on the end. Three ball detents help secure it in place when itโs folded and a finger hole makes it easy to pop out and extend. Having a moving part introduces the possibility of moving out of square if itโs not dialed in just right, though.


Folded, thereโs the tiniest bit of rise onto the extension. Weโre talking well under 1mm and not enough to throw your line off if you canโt use it extension side up.
The extension folds out a little beyond 180ยบ and it will flatten out to match your material.

To see just how level it is from the base through the extension, we set it on a level to see if comes through. Thereโs a slight amount that does, but weโre talking about so little that the finest pencil mark you can make is thicker.

Long-Term Durability
We really like what weโre seeing from this speed square so far, but weโve only been using it for a couple of months. The only major long-term judgment weโre holding off on is how the pivot point wears. Right now, itโs tight. However, itโs bound to wear and get at least a small amount of wiggle to it eventually.

When youโre done with your marking, be sure to close the extension back in. It already hinges out a little beyond 180ยบ and while itโs not weak, it wonโt take a tremendous amount of force to bend it out of square or break it.
Still, weโre not talking about a $200 level. Itโs a sub-$20 square and replacing it occasionally from loss, damage, or wear is an inevitability for most of us anyway.
Measurements
Because of the squareโs design, the hypotenuse side doesnโt let you mark across its entire length. Itโs essentially the same distance as a 6-inch square, so thatโs not likely to be a problem.
The scribe marks are properly set from the inside of the base from 1 inch at the first scribe point to 5-1/2 inches near the end in the folded position. Extended, you have scribe points out to 11-1/2 inches and a total length of 12-1/4 inches from the inside of the base.

Flip it around and the extension gives you 3/4-inch to 5-1/2 inches.
The base itself is 7-1/4 inches long.
Pricing
Retail pricing on the Crescent Lufkin extendable square is $19.99 from retailers such as Acme Tools and you may be able to find it for a little less on Amazon. Quality 7โณ squares run $10 โ $15 and 12โณ models are around $20, so we think the pricing on this is fair.
Get it on Amazon Get it at Acme Tools
The Crescent Lufkin Extendable Square Might Not Be the Only Option
Itโs likely no coincidence that Home Depot has a similar extendable square under the Husky brand. It sports a black main body with gray extension and runs $17.97. They look identical, so if youโre waiting for Amazon or Acme Tools to get the Crescent version in stock, you can swing by your local Home Depot store and grab one.
The Bottom Line
The Crescent Lufkin extendable square has proven itself to be a very handy addition to our shop. Its size is more manageable than a 12-inch rafter square and itโs more versatile than a 6-inch or 7-inch speed square.ย If you use a square frequently for professional or DIY use, give it a shot. We donโt think youโll be disappointed.
