# How are bolt sizes specified?

Contents

A bolt’s size is classified based on a number of dimensions, namely the bolt’s diameter, length of shank, thread pitch, grade, thread length and head size. Bolts can me specified in metric using millimeters, but the standard, internationally-recognized descriptions of bolt sizes are in inches.

## How are bolt sizes written?

Unified screw diameters are measured in inches — lowest to highest as 0 to 10. Measurements equal 0.060″ + 0.013″ x measured diameter. … Screws larger than 10 are listed as fractions of an inch. For example: 1/8-10 x 4/6 has a major diameter of 1/8th of an inch.

## How do you specify a bolt?

Metric fastener threads are also specified according to thread pitch, which is the distance between adjacent threads, again in millimeters. This is represented by the last number in a metric bolt’s designation. For example, a bolt labelled M10 x 1.5 is a metric bolt with a 10 mm diameter and 1.5 mm between threads.

## What does M14 x2 mean?

Inch. Fine. 0.025. 40. The threads of an M14-2.0 screw, which is coarse, are spaced 0.079 inches (2.0 mm).

## What are the metric bolt sizes?

Metric clearance and tapping drill hole sizes.

Size Clearance Hole mm Tapping Drill (std Pitch)
M5 5.5 4.2 mm
M6 6.5 5.0 mm
M8 9 6.75 mm
M10 11 8.5 mm
IT IS INTERESTING:  What is a Grade A2 bolt?

## How can you tell if a bolt is metric or standard?

Telling the difference between a metric and imperial bolt is easy. If the bolt has lines on the head its standard or imperial. If the bolt has numbers on the head then its metric.

## How do I know if my bolts are standard or metric?

For both metric and standard bolts, the head size is the distance across the flats. For standard bolts, the head size is measured in inches or fractions of an inch. For metric bolts, head size is measured in millimeters. However, metric bolt head size is measured in millimeters.

## How do I know if I have a M6 bolt?

Metric threads are used outside of the USA, and commonly in products by HP and other global entities. You can identify an M6 screw by measuring the diameter with a ruler. It’ll be 6 mm, or slightly more than 7/32 inches (0.228″).

## Is 5/16 The same as M8?

Well, quick answer is no. They are not the same and they are not interchangeable, although they can work under certain circumstances. The most important part is understanding the meaning of M8 and 5/16 to refer to the size of a metric screw or bolt, so then we can see why they aren’t the same thing!

## What are M4 screws?

They’re made from a durable carbon steel and come with a nut for tightening metal surfaces together. The M4 machine screw has a thread diameter of 4 millimetres, in simple terms the M stands for millimetres followed by the size – in this case 4 mm.

IT IS INTERESTING:  What size plugs for 8mm screws?

## What does M12 mean?

6. Those are metric screw dimensions. M10 means a 10 millimeter outer diameter for the bolt or whatever piece it is; M12 means 12 millimeters. The part after the ‘x’ is the pitch — how many mm a thread is wide. To figure out which you have, you can measure the existing part with calipers and a thread gauge.