# How to Convert a Metric Feeler Gauge to Standard

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#### Things You'll Need

• Metric feeler gauge

• Mechanical gap

• Calculator

Feeler gauge blades are either sheet metal or wires.

Correct measurements of any tight tolerances are a necessity to ensure the proper operation of your mechanical and electrical equipment. Feeler gauge blades have the width -- in metric or standard units -- of the blade stamped near their base. When using a feeler gauge with only metric sizes stamped on the blade, you can still determine the standard size by converting the metric dimension. A simple mathematical equation allows you to precisely convert a metric dimension to a standard equivalent.

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## Step 1

Slide one blade of a metric feeler gauge into a mechanical gap to determine the gap width. The correct blade will slide into the gap while slightly contacting the top and bottom of the gap.

## Step 2

Read the number stamped on the bottom of the feeler gauge blade matching the size of the mechanical gap.

## Step 3

Enter the metric measurement into a calculator. Multiply the metric number by 0.039 to convert the metric dimension to standard units. For example, a feeler blade 3 mm thick multiplied by 0.039 equals 0.117 or 3/32 inch.