What does m8 screw mean

Metric fasteners are available with either coarse or fine thread pitches with some metric bolt sizes offering extra fine thread pitch options. It is worth noting that metric bolts with a coarse thread pitch have more threads per inch they are more closely spaced than comparable imperial bolts.

The length of a metric bolt is measured and defined in exactly the same way as imperial, inch-based bolts and fasteners. Socket head, pan head, button head and hex head bolts are measured from the underside of the bolt head to the end of the shaft. For flat head bolts, the length includes the bolt head height and for dome head bolts the length is measured from the thickest, highest point on the curved head. The defined diameter of metric bolts is actually slightly larger than the actual diameter of the bolt shaft.

The necessary tapping hole size can be easily calculated by deducting the thread pitch from the metric bolt diameter. For example, an M8 bolt with a standard coarse thread pitch of 1. But if the M8 bolt had a fine pitch thread of 1mm then the diameter of the hole required for tapping would be 7mm.

The following table provides examples of clearance hole sizes, standard or coarse thread pitches along with fine thread pitches and their corresponding tapping hole sizes. Using the correct tool for the job is always essential. If you have any questions or uncertainty regarding the fasteners you need then remember that we are here to help. So buy now with confidence - and join the thousands of happy customers we have helped over the last 20 years Just call us on Web Design by Worldwide Webdesign.

Need Help or Advice? For example, M8 is a metric screw and has a diameter of 8mm. Which size? The most important factor in screw selection is length. The general rule of thumb is that the screw should enter at least half the thickness of the bottom material, e. If the nut is metric, count the number of lines on the tape measure to find the measurement.

If you count 9 lines, the size is a 9-mm millimeter nut. If the nut is US standard, count the smallest lines on the tape measure in sixteenths. Add the sixteenths together to find the size.

Diameter: the larger the number, the larger the screw or bolt. Threads per Inch: the larger the number, the more fine the thread. Length: the larger the number, the longer the screw or bolt. M6 threads are 6mm metric screws.

The standard metric rack screw is called M6 x 1. Apr 24, May 12, For instance, the most common bolt size used on bicycles is 5 x.

Dec 11, For example, an M10x1. To simplify metric thread callouts, the international ISO standard for metric threads eliminates the pitch callout on coarse threads. Classes 2A and 2B offer optimum thread fit that balances fastener performance, manufacturing, economy, and convenience. M1 rifle aka Garand. M6 refers to a metric 6 mm screw. The outside diameter of the threads is 6 mm. The standard metric rack screw is actually an M6 x 0. The number 0. Which is bigger M8 or M10?

Is M8 8mm? What is M10 thread? How big is a M10 bolt? What size head is a M8 bolt? What are standard bolt sizes? What size bolt has an 18mm head? What size bolt is a 15mm head? Does M12 mean 12mm? What are the most common metric bolt sizes? How can you tell if a bolt is metric? How do I know what size bolt I need? The bolts always use coarse threads when the pitch measurement is missing from a metric bolt specification.

While working with inch fasteners is commonplace for you, the pitch may be rather perplexing. It is because of the distance between the threads. The distance from one thread to the next in the example shown is 1. Screws that are defined as threads per inch, or sometimes termed pitch, are called inch fasteners.

For you to measure the metric fastener threads per inch, first convert pitch from millimeters to inches multiband by 0. M8 screws have non-interchangeable thread sizes because of the different thread angles and pitches.

For your reference, here are the standardized sizes according to fine and coarse. The standard size for the Metric Coarse is M8 x 1. Meanwhile, we have M8 x 1 for the Metric Fine. Since metric screw units correlated to different sized nuts and drilled holes, manufacturers developed specific standards for screws.

Additionally, the screws are made with thin or coarse threads that represent the pitch of the line of a screw. Coarse-thread screws have a lower susceptibility to seizing, cross-threading, and galling. The opposite is true for fine-thread screws. Fine-thread screws are more likely to come loose from movement and can be tapped and adjusted more easily. There is no need to identify the thread type of screws that cut their threads in a soft material. For this reason, it is indeed essential to know the features and requirements of M8 screws before purchasing them.

The definition of thread length is included in the metric bolt standard. However, if it is not mentioned, then a coarse pitch is assumed. Metric bolts are offered in coarse or fine thread pitch with extra fine pitch choices on certain diameters.

Additionally, you have to remember that metric bolts have more threads per inch than equivalent imperial bolts. It is because they have a coarser thread pitch. The standard thread length for an M8 screw is mm, and the shorter size is 22 mm. Meanwhile, the standard for the M8 screws with a length of longer than mm is 28 mm.

The diameter of metric bolts is more than the shaft diameter. Because the shaft diameter of an M8 bolt is under 8mm, it should fit through an 8mm hole.