Gauge Models

Keyway Tri-Gauge Models

Easy-to-Use Keyway Tri-Gauge Saves Time, Money, & Parts. Proven in Thousands of Applications.


Keyway Tri-Gauge Model R

Choose Model R for Shafts from 5/8″ (16 mm) to 6″ (154mm) in Diameter

Keyway Tri-Gauge Model L

Choose Model L for Shafts from 6″ (154mm) to 16″ (407mm) in Diameter

Keyway Tri-Gauge Model S

Choose Model S for Shafts Smaller than 1/2″ (12.7mm) in Diameter


A separate accessory, custom made to fit your specific tapered shafts, is used in conjuction with the Keyway Tri-Gauge to take the three critical keyway measurements at the job site. Only the application (tapered shafts) is somewhat different. There are no differences in the many advantages gained with the easy to achieve accuracy of the Keyway Tri-Gauge. To order your gauge for tapered shafts email with your shaft dimensions.

Keyway Tri-Gauge Digital Readout
Digital readout available on models R and L

Keyway Tri-Gauge Accessory 1

Keyway Tri-Gauge Accessory 2

Woodruff Gauge

To accurately check the centering of keyways in Woodruff Keys, from American Standard #608 to the largest, use the Woodruff Gauge Model LW. To measure the centering of keyways in Woodruff Keys, American Standard #404 to #807, use the Model SW. Both models offer the simple procedure and great precision of the Keyway Tri-Gauge.

Keyway Tri-Gauge Woodruff Gauge

Woodruff Key

Bottomless Keyway on Bushing