# What does m8x1 25 6H mean?

## What does m8x1 25 6H mean?

m8 means metric thread 8mm of ISO standard and 6H refers to tolerance of threaded hole (know more about it in ISO 2768) 2 0.

**What is 6H tolerance class?**

The 5g indicates the tolerance class for the pitch diameter and 6g is the tolerance class for the major diameter. For example: M12 x 1 – 6H/5g6g indicates a tolerance class of 6H for the nut (female) thread and a 5g tolerance class for the pitch diameter with a 6g tolerance class for the major diameter.

**What is meant by m8x1 25 thread?**

M means metric. 8 means 8mm nominal diameter (the thread will be less than 8 mm at the widest point) X 1.25 means 1.25 mm per thread (thanks the standard coarse pitch for this thread)

### What is tolerance class thread?

Tolerances are written as a combination of a tolerance band, signified by an alphabetic letter, and a tolerance class, signified by a number. As an example, a common screw thread tolerance is 5g6g, which indicates a 5g tolerance on its pitch diameter, and a 6g tolerance on its external (thread) diameter.

**What does D6 mean on a tap?**

D6 = Basic plus . 0030 = max. tap P.D. CHART 1A. Pitch Diameter Limits for taps to 1″ diameter inclusive: L1 = Basic to Basic minus .

**What does H mean on a thread?**

The pitch diameter tolerance for each class of thread establishes how loose or tight the threaded assembly will be before it is tightened. H (high) represents a pitch diameter that is larger than the basic pitch diameter, and L (low) represents a pitch diameter that is smaller.

#### What is the H value on a tap?

H (high) represents a pitch diameter that is larger than the basic pitch diameter, and L (low) represents a pitch diameter that is smaller. The number after the H or L, indicates the amount it is different than the basic pitch diameter.

**What is the difference with H for taps?**

The difference in size from one H limit to the next is 0.0005″ increments for taps through 1″ diameter. Sizes over 1″ diameter are separated by . 001″ diameter increments. If the threads in the part are too loose, smaller numbers such as H1 or H2 are used.

**How is TPI measured?**

Measuring Imperial Thread Pitch As the name suggests, TPI is measured by counting the number of thread peaks along a 1 inch length. The TPI measurement is then often affixed to the diameter of the thread to form a common imperial thread size, e.g. ‘1/4-20’, which would denote a ¼ inch diameter, and 20 threads per inch.