StewMac Flexible Shop Rule

StewMac Flexible Shop Rule, 6" Flexible Rule
6" Flexible Rule Item # 6240 In stock, ready to ship!
StewMac Flexible Shop Rule, 15cm Flexible Rule
15cm Flexible Rule Item # 6240-M In stock, ready to ship!
StewMac Flexible Shop Rule, 12" Flexible Rule
12" Flexible Rule Item # 6241 In stock, ready to ship!
StewMac Flexible Shop Rule, 30cm Flexible Rule
30cm Flexible Rule Item # 6241-M In stock, ready to ship!
StewMac Flexible Shop Rule, 18" Flexible Rule
18" Flexible Rule Item # 6242 In stock, ready to ship!
StewMac Flexible Shop Rule, 45cm Flexible Rule
45cm Flexible Rule Item # 6242-M In stock, ready to ship!
StewMac Flexible Shop Rule, 24" Flexible Rule
24" Flexible Rule Item # 6243 In stock, ready to ship!
StewMac Flexible Shop Rule, 60cm Flexible Rule
60cm Flexible Rule Item # 6243-M In stock, ready to ship!
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StewMac Flexible Shop Rule

Accurately measure around curves
Our flexible rules finally let you take precise measurements on all the arches, curves, and tricky shapes on guitars and more.

From acoustic sides and cutaways to necks and arched tops, you need a rule that will conform to these shapes to get a truly accurate measurement. Our flexible rules make it easy—they've got the same accuracy and features of our Shop Rule, but with thinner and flexible chrome steel construction. The narrow 0.020" (0.5mm) thickness also fits into most fret slots too.

And they won't fight you like metal tape measures or flop around like vinyl tape measures do. With their accurate markings, center-finder, and vertical end scales these rules will never leave your bench.

Accuracy you can count on

Each rule is satin chrome steel with sharp black etchings that are easy to see even in poor light. It easily accepts pencil marks, too. The inch marks are in 16ths, 32nds and 64ths—for fast readings and extreme precision. The metric marks are in centimeters, millimeters, and 0.5 millimeters.

Centering rule

Each rule also includes a centering rule on the reverse. With zero at the center, this rule extends left and right to locate the center of a neck, bridge saddle, or body quickly and accurately.

Vertical end rules

For even more utility, each end is also a vertical rule. The precise scale (1/32" or 1mm increments) is ideal for measuring fret slot depth and the height of saddles, nuts, and pickups.

Measure inside and out

The flexibility makes them easy to use outside and inside the instrument—essential for repairs. Get your measurements for binding, purfling, and linings all with the same tool.

The multiple sizes make these perfect for the everyday jobs in your shop. Here's just a few uses we've found for the four different sizes:

6" rule or 15cm rule: perfect for small jobs like measuring the curves on a shaped acoustic bridge, headstock, the back of necks, and even fret slot depth. It also works great for measuring between braces tucked into the linings on acoustic guitars.

12" rule or 30cm rule: ideal for laying out battery boxes and sound ports on acoustic guitars, as well as measuring the neck to heal transitions on acoustic necks.

18" rule or 45cm rule: the right size for measuring the sides of smaller instruments like mandolins, ukuleles, as well as inside and outside acoustic guitars. It's also the perfect length for laying out an entire guitar fretboard, from frets to inlay locations.

24" rule or 60cm rule: long enough for determining binding and lining measurements. Not only that, it's the right length for measuring scale length, finding the neck angle, determining bridge locations, and laying out neck blanks.


  • Flexible chrome plated steel
  • Satin finish for easy reading and marking
  • Extreme precision: markings in 16ths, 32nds, and 64ths or cm, mm, and 0.5 mm
  • Multiple scales on each rule: vertical, horizontal, and centering
  • 0.020" (0.5mm) thickness, fit in most fret slots


  • Each rule is 0.75" tall x 0.020" thick (19mm x 0.5mm)
  • Available in four standard and metric lengths: 6", 12", 18", 24" and 15cm, 30cm, 45cm, 60cm.

Looking for a rigid rule? Our Shop Rules have the same precise measurement features, but are double the thickness for a solid feel. They stay straight for marking out lines and tracing plans with extreme accuracy.

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