What Metric Fastener Drive Type Should You Be Using?

Like most aspects of construction and manufacturing, choosing the proper tool for the job goes a long way toward determining the project’s success. Selecting a metric fastener’s drive recess (the slot or hole into which the driving tool is inserted) is no different. Drive recesses, from Phillips head screws to more unusual shapes and specialized uses all have advantages and disadvantages. Take a look at some of the drive types Mr. Metric offers to learn about which style is right for your job.

Ensure Proper Tightening & Removal of Metric Fasteners With the Right Drive Type

metric screw slottedSlotted – The first and still one of the most common varieties, slotted metric screws are inexpensive and come in virtually any head shape desired. They are also the easiest to torque when using a screwdriver to remove corroded or frozen fasteners, so they are often used when field installation and/or removal is necessary. However, they are unsuited for automated driving because the single slot allows the bit too much tolerance, and slippage and off-center engagement can occur. Continue reading

Understanding & Applying Proper Torque for Metric Fasteners

Torque Explained

Tightening a nut onto a bolt causes the bolt to stretch slightly. Much like a spring, the bolt resists this stretching, and its tendency to return to its natural state creates clamping action between, say a cylinder head and a manifold, or two pieces of sheet-metal housing.

It is critical to the component’s operation that the amount of tension created holds the parts together strongly enough to prevent their separation by outside forces such as the machine’s vibration, the load stress generated during operation, gasket creep, temperature fluctuations, and more. Too much torque, however, can stretch the fastener too much, to the point where it chips, breaks, or yields. Bolts and screws are rated by their “proof load” – how much tension they can withstand before they fail. As a rule of thumb, torque a “clamp load” (also known as “preload”) 75 percent to 90 percent of the proof load is optimal.

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Torque Relationship Chart

 

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Fully and Partially Threaded Metric Bolts: Which is Right for Your Job?

metric boltIt’s easy to get confused when deciding whether to use a fully or partially threaded metric bolt for a particular assembly. Often, people simply use whatever bolt is available—assuming that if it fits, it’s probably close enough. However, it’s important to bear in mind that the size of a bolt hole is just one small part of the overall engineering that goes into a completed assembly.

How a bolt grips and how loads are distributed by the bolt, are critical factors in the strength of a union. Bolts grip and distribute differently, depending on variables such as thread pitch, head size and, of course, whether the bolt is fully or partially threaded. To ensure proper grip and resistance to breakage, it’s important to use a bolt that meets the original engineering specs.

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Metric Fasteners Keep the Medical Industry Running

medcartOver time, metric fasteners can wear out, work loose, or break off. The more a piece of equipment is used, the more often metric fasteners will need to be replaced. With a 24/7 schedule, few industries are as hard on equipment as the medical industry. Everything from handcarts to ultrasounds are used and relied on constantly within the medical industry by rotating shifts of employees.

This puts a lot of strain on medical equipment, and makes repairs a frequent problem. Finding the right metric fasteners is key to getting medical equipment up and running again.

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Finding the Right Metric Nut is No Easy Task

With all of the nuts in the world, it can be hard to figure out which one is right for your assembly. To help you along with selecting the proper product for your project, here’s a brief rundown of some of the most common metric nuts and their applications.

  1. Metric All Metal Nuts
    alll metalThese general purpose nuts are commonly found on cars, farming machinery, and in metal working industries. They’re very tough, reusable, and provide a solid connection.

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Maintain Your Bike & Ride Smoothly with Metric Fasteners

bikeSpring is in the air, and that means a lot of people will be dusting off their bicycles and heading out for long rides. The question is, are those bikes ready for another season of two-wheel adventures? Worn or loose fasteners and bolts can turn a pleasant ride into a nightmare. Before hopping on your bike, make sure it’s up to the task.

A bicycle is made up of a surprising number of parts. All of those parts are held together by various metric bolts and washers. If any one of those metric fasteners are worn or incorrectly sized, parts can come loose and you may be at risk for injury. Here, we’ll take a look at some of the most important systems of a bicycle, and the most common metric fasteners used by those systems.

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The Evolution & Use of Metric Kep Nuts

Some things have been around so long that it’s easy to forget that there was a time they didn’t exist. These items fill their need so easily and so completely that we can’t imagine a time when people had to get by using other means. One of these items is the “kep” nut. This nut has been around for nearly a century, and many assemblers couldn’t imagine life without it.

metric kep nutsA Little History
The kep nut was invented in 1923 by Shakeproof Screw and Nut Lock Company. The “kep” in kep-nut comes from the name Sha(kep)roof. Now owned by Illinois Tool Works (ITW), the kep nut revolutionized manufacturing and assembly just as assembly lines were taking off. Continue reading

The Different Metric Machine Screw Heads and Their Uses

metic machine screwWhen it comes to keeping things together, engineers, designers, and builders overwhelmingly choose metric machine screws. They’re in everything from kitchen cabinets to deep-space probes. Given the wide variety of things put together with metric machine screws, it’s no surprise that there is such a wide variety of metric screws to choose from. Learn about the different types of metric machine screws and when to use them.

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ISO 9001:2008 Certification: What it Means to You

The establishment of the International Organization for Standardization (ISO) is based on the need to facilitate international trade by promoting development of universal standards. Having been in place for over a decade now, the ISO 9001:2008 Certification is a universal method used by both customers and companies to control the quality of output.

ISO-Certified-Co-Logo-BlueIt is a framework of business management ensuring continued improvements in all aspects of the business. The external assessment on a regular basis ensures maintenance of these business practices.

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Metric Fastener Markings: What Do They Mean?

Most people would be amazed by the amount of information that can fit on the head of a bolt. As you may already know, information about the diameter, length, and thread pitch of a fastener can often be found on its head. However, there’s a lot of other information that manufacturers put on the head of a bolt that you may not know about. That information can make a big difference in the type of bolt you choose for your application. Here, we’ll look at some of the markings, and what they mean in terms of real-world applications

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