How to Read Metric Bolts

Converting the bolt pattern from metric to inches takes just a few minutes.
••• Hemera Technologies/AbleStock.com/Getty Images

Many metric bolts denote the use of metric measurements with an "M" at the start of the bolt designation, such as "M9x1.2x15." Metric bolts list measurements in millimeters. Besides using metric measurements, a metric bolt uses the distance between the threads rather than the thread pitch, used in American measurements, which is the number of threads per inch.

    Determine the diameter of the bolt by looking at the first number. For example, if the metric bolt was M14x1.5x25, it would have a diameter of 14 millimeters.

    Determine the distance between threads by looking at the second number. For example, if the metric bolt was M14x1.5x25, it would have 1.5 millimeters between threads.

    Determine the length of the metric bolt by looking at the third number. For example, if the metric bolt was M14x1.5x25, it would have a length of 25 millimeters.

    Look on the bolt head for the number denoting the strength of the bolt. The bigger the number, the stronger the bolt.

    Warnings

    • Do not try to use metric and American bolts together. They will not fit exactly.

Related Articles

How to Measure Electric Motor Torque
How to Calculate Mechanical Advantage Screws
The Dimensions of a NEMA 56C
Difference Between Centimeters & Meters
How to Convert Horsepower to Foot Pounds
How to Convert 26 Tpi to Metric
How to Read a Metric Micrometer
How to Calculate the Grip Length of a Bolt
How to Read a Ruler in Centimeters, Inches & Millimeters
How to Convert MPa to N/mm^2
How to Find Bearing Numbers by Size
How to Convert MBH to Tons
How to Read a Metric Tape Measure
How to Calculate a Steel I-Beam's Weight
How to Use a Metric Scale Ruler
How to Calculate Gear Pitch
How to Measure Square Centimeters
How to Find the Volume of a Piece of Paper
How to Read an Engineer's Elevation Pole
How to Convert 46 CM Into Inches

Dont Go!

We Have More Great Sciencing Articles!