The difference between using the right screw and one that’s almost right can be the difference between securing a part and ruining it. A screw thread pitch gauge is essential to match a screw or bolt with a threaded fitting or nut. Using the gauge is easy. Reading a thread pitch takes only a moment and can save time that might otherwise be spent cleaning and tapping stripped or cross-threaded fittings.
Unfold a leaf from the body of the gauge.
Press the serrated edge of the leaf against the threaded edge of the bolt or screw.
Check the fit between the edge of the gauge and the threads.
Continue checking the threads of your bolt or screw with successive leaves until the serrations on the gauge fit snugly into the threads.
Read the number stamped into the leaf. This will be your thread pitch.