Sterling Tool Works Double Square
This precision square is supplied with one traditional graduated rule and a dovetailing rule providing a very versatile tool with many uses. The standard rule provides a wonderful compact square with excellent accuracy rivaling common machinist square accuracies of .001” per inch, per U.S. federal standard: GGG-S-656E. Available with either a 4″ or 6″ precision etched rule with chrome satin finish with blackened etches that is easy on your eyes for excellent contrast and improved accuracy.
The included Sterling “Dovetailing Blade” is incredibly handy for checking the squareness of your dovetails to ensure excellent fit and “gap less” joints after assembly. The reduced size of one end of the un-graduated rule allows precise checking of squareness in even some of the tightest “London style” dovetails. Regular size rules simply cannot reach into the spaces the Sterling Dovetailing Rule can. The Dovetailing Rule / Blade is hardened, precision ground and finished with the same satin Chrome finish as the standard rule.
The powder coated square casting provides the accuracy required but avoids the stock-heavy feel of a solid machinist’s square, providing excellent balance and feel. Rules lock securely in any position from full left to full right with the tightening of the knurled thumbscrew.
The Sterling Double Square is available with these precision etched rules:
4” Length with English/Metric graduations = .5mm, 1mm, 32nds, 64ths
6” Length with English/Metric graduations = .5mm, 1mm, 32nds, 64ths
6” Length with 4R graduations = 8ths, 16ths, 32nds, 64ths
Superior quality – Made in USA.
The Sterling Dovetailing Blade is also available separately without the double square. I cannot guarantee that the Dovetailing Rule will fit ALL other makers squares but I have tried a handful of other makers 6” combination squares I had on hand such as Starrett, Goddell Pratt, Brown and Sharpe and the dovetailing rule clamped perfectly in both vintage and contemporary squares.